70911 79606 tec-appendix

padi.com A-1

InstructorGuide Appendix

AppendixTableofContents

DSAT Tec Diver Course Key Dive Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3

DSAT TecRec Dive Planning Slate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6

DSAT TecRec Dive Planning Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7

DSAT TecRec Equipment Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-8

CNS Surface Interval Credit Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-9

Oxygen Exposure Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-9

SAC Conversion Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-10

Maximum Depths in Feet of Seawater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-11

Maximum Depths in Metres of Seawater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-12

Equivalent Air Depth and Oxygen Management Table – Imperial . . . . . . . . . . . . . . . . . . . . . . A-13

Equivalent Air Depth and Oxygen Management Table – Metric . . . . . . . . . . . . . . . . . . . . . . . . A-24

Hand Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-36

Independent Study Assignments with Knowledge Review Answer Keys . . . . . . . . . . . . . . . A-39

Independent Study Assignments and Blank Knowledge Reviews . . . . . . . . . . . . . . . . . . . . . . . A-95

Other Delivery Content Hand Outs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-149

Liability Release and Express Assumption of Risk for Technical Diving . . . . . . . . . . . . . . A-205

Liability Release and Express Assumption of Risk for Discover Tec Diving . . . . . . . . . . . A-207

Application – Instructor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-209

Standard RSTC Medical Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-211

Tec Diver Statement of Understand and Learning Agreement . . . . . . . . . . . . . . . . . . . . . . . . . A-217

Tec 40 Answer Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-218

Tec 45 Answer Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-220

Tec 50 Answer Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-222

Exam Answer Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-224

79606_Tec-Appendix.indd 1 10/26/09 12:52 PM

A-2 padi.com

Appendix InstructorGuide


padi.com A-3


TecDiverCourseKeyDiveStandardsTec40TrainingDiveOne Environment: Confined water or limited open water with ready access

to water shallow enough to stand up in. Depths: Minimum: 2.5 metres/8 feet Maximum 10 metres/30 feet Decompression: No stop only Gases: Air, EANx up to EANx50 Ratios: 6:1, 8:1 with one or more certified assistants

Tec40TrainingDiveTwo Environment: Open water Depths: Minimum: 10 metres/30 feet Maximum: 18 metres/60 feet Decompression: No stop only Gases: Air or EANx up to EANx50. Ratios: 6:1, 8:1 with one or more certified assistants

Tec40TrainingDiveThree Environment: Open Water Depths: Minimum: 15 metres/50 feet Maximum: 27 metres/90 feet Decompression: No stop only Gases: Air, EANx up to EANx50 Ratios: 4:1, 6:1 with one or more certified assistants

Tec40TrainingDiveFour Environment: Open Water Depths: Minimum: 26 metres/85 feet Maximum: 40 metres/130 feet Decompression: up to 10 minutes total decompression time based on

breathing bottom gas throughout the dive (no accelerated decompression) Gases: Air, EANx up to EANx50 Ratios: 3:1, 4:1 with one or more certified assistants

Tec45TrainingDiveOne Environment: Confined water or limited open water with ready access

to water shallow enough to stand up in. Depths: Minimum: 2.4 metres/8 feet Maximum 10 metres/30 feet Decompression: No stop only Gases: Air or EANx, recommended that all blends be breathable at

maximum dive depth Ratios: 6:1, 8:1 with one or more certified assistants


A-4 padi.com


Tec45TrainingDiveTwo Environment: Open water Depths: Minimum: 12 metres/40 feet Maximum: 18 metres/60 feet Decompression: No stop only Gases: Air or EANx, recommended that all blends be breathable to


Tec45TrainingDiveThree Environment: Open Water Depths: Minimum: 18 metres/60 feet Maximum: 30 metres/100 feet Decompression: No stop only Gases: Air, EANx or oxygen Ratios: 4:1, 6:1 with one or more certified assistants

Tec45TrainingDiveFour Environment: Open Water Depths: Minimum: 27 metres/90 feet Maximum: 45 metres/145 feet Decompression: single gas decompression, gas switch for conservatism, Gases: Air, EANx or oxygen Ratios: 3:1, 4:1 with one or more certified assistants

Tec50TrainingDiveOne Environment: Confined water or limited open water with ready access to water

shallow enough to stand up in. Depths: Minimum: 2.4 metres/8 feet Maximum 10 metres/30 feet Decompression: No stop only, five stop simulated decompression Gases: Air or EANx, recommended that all blends be breathable at


Tec50TrainingDiveTwo Environment: Open water Depths: Minimum: 12 metres/40 feet Maximum: 24 metres/80 feet Decompression: No stop only, 30 minutes simulated decompression Gases: Air or EANx, recommended that all blends be breathable to



padi.com A-5


Tec50TrainingDiveThree Environment: Open Water Depths: Minimum: 30 metres/100 feet Maximum: 50 metres/165 feet Decompression: Decompression dive with two decompression gases Gases: Air, EANx or oxygen Ratios: 3:1, 4:1 with one or more certified assistants

Tec50TrainingDiveFour Environment: Open water Depths: Minimum: 40 metres/130 feet Maximum: 50 metres/165 feet Decompression: Decompression dive with two decompression gases Gases: Air, EANx or oxygen. Trimix permitted within limited conditions. Ratios: 3:1, 4:1 with one or more certified assistants


A-6 padi.com



padi.com A-7



A-8 padi.com



padi.com A-9



A-10 padi.com



padi.com A-11



A-12 padi.com



padi.com A-13


OTU / CNS%Depth EAD PO2 Min Min

10 10 0.27 –– 0.00%15 15 0.31 –– 0.00%20 20 0.34 –– 0.00%30 30 0.40 –– 0.00%40 40 0.46 –– 0.00%50 50 0.53 0.09 0.14%60 60 0.59 0.24 0.14%70 70 0.66 0.38 0.17%80 80 0.72 0.50 0.22%90 90 0.78 0.62 0.22%100 100 0.85 0.74 0.28%110 110 0.91 0.85 0.33%120 120 0.97 0.96 0.33%130 130 1.04 1.06 0.42%140 140 1.10 1.16 0.42%150 150 1.16 1.27 0.48%160 160 1.23 1.37 0.55%170 170 1.29 1.46 0.55%180 180 1.36 1.56 0.67%

OXYGEN CONTENT 21%OTU / CNS%

Depth EAD PO2 Min Min

10 9 0.29 –– 0.00%15 14 0.32 –– 0.00%20 19 0.35 –– 0.00%30 29 0.42 –– 0.00%40 39 0.49 –– 0.00%50 49 0.55 0.16 0.14%60 59 0.62 0.31 0.17%70 69 0.69 0.44 0.17%80 79 0.75 0.57 0.22%90 88 0.82 0.69 0.28%100 98 0.89 0.81 0.28%110 108 0.95 0.92 0.33%%120 118 1.02 1.03 0.42%130 128 1.09 1.14 0.42%140 138 1.15 1.25 0.48%150 148 1.22 1.35 0.55%160 158 1.29 1.46 0.55%170 167 1.35 1.56 0.67%180 177 1.42 1.66 0.83%

OXYGEN CONTENT 22%


10 9 0.30 –– 0.00%15 14 0.33 –– 0.00%20 19 0.37 –– 0.00%30 28 0.44 –– 0.00%40 38 0.51 0.03 0.14%50 48 0.58 0.22 0.14%60 58 0.65 0.36 0.17%70 67 0.72 0.50 0.22%80 77 0.79 0.63 0.22%90 87 0.86 0.76 0.28%100 97 0.93 0.88 0.33%110 106 1.00 0.99 0.33%120 116 1.07 1.11 0.42%130 126 1.14 1.22 0.48%140 136 1.21 1.33 0.55%150 145 1.28 1.44 0.55%160 155 1.35 1.55 0.67%170 165 1.41 1.65 0.83%180 175 1.48 1.75 0.83%



10 8 0.31 –– 0.00%15 13 0.35 –– 0.00%20 18 0.39 –– 0.00%30 28 0.46 –– 0.00%40 37 0.53 0.10 0.14%50 47 0.60 0.27 0.14%60 56 0.68 0.42 0.17%70 66 0.75 0.56 0.22%80 76 0.82 0.69 0.28%90 85 0.89 0.82 0.28%100 95 0.97 0.95 0.33%110 105 1.04 1.07 0.42%120 114 1.11 1.18 0.48%130 124 1.19 1.30 0.48%140 133 1.26 1.41 0.55%150 143 1.33 1.52 0.67%160 153 1.40 1.63 0.67%170 162 1.48 1.74 0.83%180 172 1.55 1.85 2.22%

OXYGEN CONTENT 24%

EQUIVALENT AIR DEPTH AND OXYGEN MANAGEMENT TABLE – IMPERIAL


A-14 padi.com



10 6 0.36 –– 0.00%15 11 0.41 –– 0.00%20 15 0.45 –– 0.00%30 24 0.53 0.11 0.14%40 34 0.62 0.30 0.17%50 43 0.70 0.48 0.17%60 52 0.79 0.63 0.22%70 61 0.87 0.79 0.28%80 70 0.96 0.93 0.33%90 79 1.04 1.07 0.42%100 88 1.13 1.21 0.48%110 97 1.21 1.34 0.55%120 106 1.30 1.47 0.55%130 116 1.38 1.60 0.67%140 125 1.47 1.73 0.83%150 134 1.55 1.86 2.22%


10 7 0.34 –– 0.00%15 12 0.38 –– 0.00%20 17 0.42 –– 0.00%30 26 0.50 –– 0.00%40 35 0.58 0.21 0.14%50 45 0.65 0.38 0.17%60 54 0.73 0.53 0.22%70 63 0.81 0.68 0.28%80 73 0.89 0.81 0.28%90 82 0.97 0.95 0.33%100 92 1.05 1.08 0.42%110 101 1.13 1.21 0.48%120 110 1.21 1.33 0.55%130 120 1.28 1.45 0.55%140 129 1.36 1.57 0.67%150 138 1.44 1.69 0.83%160 148 1.52 1.81 2.22%170 157 1.60 1.92 2.22%

OXYGEN CONTENT 26%


10 7 0.35 –– 0.00%15 11 0.39 –– 0.00%20 16 0.43 –– 0.00%30 25 0.52 0.06 0.14%40 34 0.60 0.26 0.14%50 44 0.68 0.43 0.17%60 53 0.76 0.58 0.22%70 62 0.84 0.73 0.28%80 71 0.92 0.87 0.33%90 81 1.01 1.01 0.42%100 90 1.09 1.14 0.42%110 99 1.17 1.27 0.48%120 108 1.25 1.40 0.55%130 118 1.33 1.53 0.67%140 127 1.42 1.65 0.83%150 136 1.50 1.77 0.83%160 145 1.58 1.89 2.22%

OXYGEN CONTENT 27% OXYGEN CONTENT 28%


10 8 0.33 –– 0.00%15 13 0.36 –– 0.00%20 17 0.40 –– 0.00%30 27 0.48 –– 0.00%40 36 0.55 0.16 0.14%50 46 0.63 0.32 0.17%60 55 0.70 0.48 0.17%70 65 0.78 0.62 0.22%80 74 0.86 0.75 0.28%90 84 0.93 0.89 0.33%100 93 1.01 1.01 0.42%110 103 1.08 1.14 0.42%120 112 1.16 1.26 0.48%130 122 1.23 1.38 0.55%140 131 1.31 1.49 0.67%150 141 1.39 1.61 0.67%160 150 1.46 1.72 0.83%170 160 1.54 1.83 2.22%180 169 1.61 1.94 2.22%

OXYGEN CONTENT 25%


padi.com A-15



10 5 0.40 –– 0.00%15 9 0.45 –– 0.00%20 13 0.50 –– 0.00%30 22 0.59 0.24 0.14%40 31 0.69 0.44 0.17%50 39 0.78 0.62 0.22%60 48 0.87 0.79 0.28%70 57 0.97 0.95 0.33%80 66 1.06 1.10 0.42%90 74 1.16 1.25 0.48%100 83 1.25 1.40 0.55%110 92 1.34 1.54 0.67%120 101 1.44 1.68 0.83%130 109 1.53 1.82 2.22%


10 4 0.42 –– 0.00%15 8 0.47 –– 0.00%20 13 0.51 0.05 0.14%30 21 0.61 0.29 0.17%40 30 0.71 0.48 0.22%50 38 0.80 0.66 0.22%60 47 0.90 0.83 0.28%70 56 1.00 1.00 0.33%80 64 1.10 1.16 0.42%90 73 1.19 1.31 0.48%100 81 1.29 1.46 0.55%110 90 1.39 1.61 0.67%120 99 1.48 1.75 0.83%130 107 1.58 1.90 2.22%

OXYGEN CONTENT 31%


10 6 0.38 –– 0.00%15 10 0.42 –– 0.00%20 15 0.47 –– 0.00%30 24 0.55 0.16 0.14%40 33 0.64 0.35 0.17%50 42 0.73 0.52 0.22%60 51 0.82 0.69 0.28%70 60 0.91 0.84 0.33%80 69 0.99 0.99 0.33%90 78 1.08 1.13 0.42%100 87 1.17 1.27 0.48%110 96 1.26 1.41 0.55%120 105 1.34 1.55 0.67%130 113 1.43 1.68 0.83%140 122 1.52 1.81 2.22%150 131 1.61 1.94 2.22%

OXYGEN CONTENT 32%



10 5 0.39 –– 0.00%15 10 0.44 –– 0.00%20 14 0.48 –– 0.00%30 23 0.57 0.20 0.14%40 32 0.66 0.40 0.17%50 41 0.75 0.57 0.22%60 49 0.85 0.74 0.28%70 58 0.94 0.89 0.33%80 67 1.03 1.05 0.42%90 76 1.12 1.19 0.48%100 85 1.21 1.34 0.55%110 94 1.30 1.48 0.55%120 103 1.39 1.62 0.67%130 111 1.48 1.75 0.83%140 120 1.57 1.88 2.22%

OXYGEN CONTENT 30%


A-16 padi.com



10 1 0.50 ---- 0.00%15 5 0.55 0.15 0.14%20 9 0.61 0.29 0.17%30 16 0.73 0.52 0.22%40 24 0.84 0.73 0.28%50 32 0.96 0.93 0.33%60 40 1.07 1.12 0.42%70 48 1.19 1.30 0.48%80 56 1.30 1.48 0.55%90 64 1.42 1.65 0.83%100 71 1.53 1.82 2.22%


10 1 0.48 ---- 0.00%15 5 0.54 0.12 0.14%20 9 0.59 0.25 0.14%30 17 0.71 0.48 0.22%40 25 0.82 0.69 0.28%50 33 0.93 0.88 0.33%60 41 1.04 1.07 0.42%70 49 1.15 1.25 0.48%80 57 1.27 1.43 0.55%90 65 1.38 1.60 0.67%100 73 1.49 1.76 0.83%110 81 1.60 1.93 2.22%


10 2 0.47 –– 0.00%15 6 0.52 0.08 0.14%20 10 0.58 0.21 0.14%30 18 0.69 0.44 0.17%40 26 0.80 0.65 0.22%50 34 0.91 0.84 0.33%60 42 1.01 1.02 0.42%70 50 1.12 1.20 0.48%80 59 1.23 1.37 0.55%90 67 1.34 1.54 0.67%100 75 1.45 1.70 0.83%110 83 1.56 1.87 2.22%


10 2 0.46 –– 0.00%15 6 0.51 0.04 0.14%20 11 0.56 0.18 0.14%30 19 0.67 0.40 0.17%40 27 0.77 0.61 0.22%50 35 0.88 0.80 0.28%60 44 0.99 0.98 0.33%70 52 1.09 1.15 0.42%80 60 1.20 1.32 0.48%90 68 1.30 1.48 0.55%100 76 1.41 1.64 0.83%110 85 1.52 1.80 2.22%


10 3 0.44 –– 0.00%15 7 0.49 –– 0.00%20 11 0.55 0.14 0.14%30 20 0.65 0.37 0.17%40 28 0.75 0.57 0.22%50 36 0.86 0.75 0.28%60 45 0.96 0.93 0.33%70 53 1.06 1.10 0.42%80 61 1.16 1.27 0.48%90 70 1.27 1.43 0.55%100 78 1.37 1.58 0.67%110 86 1.47 1.74 0.83%120 95 1.58 1.89 2.22%


10 3 0.43 –– 0.00%15 8 0.48 –– 0.00%20 12 0.53 0.10 0.14%30 20 0.63 0.33 0.17%40 29 0.73 0.52 0.22%50 37 0.83 0.71 0.28%60 46 0.93 0.88 0.33%70 54 1.03 1.05 0.42%80 63 1.13 1.21 0.48%90 71 1.23 1.37 0.55%100 80 1.33 1.52 0.67%110 88 1.43 1.67 0.83%120 97 1.53 1.82 2.22%

OXYGEN CONTENT 33%

OXYGEN CONTENT 35%


OXYGEN CONTENT 36%

OXYGEN CONTENT 34%


padi.com A-17



10 -2 0.56 0.17 0.14%15 2 0.63 0.32 0.17%20 5 0.69 0.45 0.17%30 12 0.82 0.69 0.28%40 20 0.95 0.92 0.33%50 27 1.08 1.13 0.42%60 34 1.21 1.34 0.55%70 41 1.34 1.54 0.67%80 49 1.47 1.74 0.83%90 56 1.60 1.93 2.22%


10 -3 0.57 0.20 0.14%15 1 0.64 0.35 0.17%20 5 0.71 0.48 0.22%30 12 0.84 0.73 0.28%40 19 0.97 0.96 0.33%50 26 1.11 1.17 0.48%60 33 1.24 1.38 0.55%70 40 1.37 1.59 0.67%80 47 1.51 1.79 2.22%


10 -1 0.55 0.14 0.14%15 2 0.61 0.29 0.17%20 6 0.67 0.42 0.17%30 13 0.80 0.66 0.22%40 21 0.93 0.88 0.33%50 28 1.06 1.09 0.42%60 35 1.18 1.30 0.48%70 43 1.31 1.49 0.67%80 50 1.44 1.69 0.83%90 57 1.57 1.87 2.22%


10 -1 0.53 0.11 0.14%15 3 0.60 0.25 0.14%20 7 0.66 0.39 0.17%30 14 0.78 0.62 0.22%40 22 0.91 0.84 0.33%50 29 1.03 1.05 0.42%60 36 1.16 1.25 0.48%70 44 1.28 1.45 0.55%80 51 1.40 1.63 0.67%90 59 1.53 1.82 2.22%


10 0 0.52 0.07 0.14%15 3 0.58 0.22 0.14%20 7 0.64 0.35 0.17%30 15 0.76 0.59 0.22%40 22 0.88 0.80 0.28%50 30 1.01 1.01 0.42%60 38 1.13 1.21 0.48%70 45 1.25 1.40 0.55%80 53 1.37 1.58 0.67%90 60 1.49 1.76 0.83%100 68 1.61 1.94 2.22%


10 0 0.51 0.03 0.14%15 4 0.57 0.19 0.14%20 8 0.63 0.32 0.17%30 16 0.74 0.55 0.22%40 23 0.86 0.77 0.28%50 31 0.98 0.97 0.33%60 39 1.10 1.16 0.42%70 47 1.22 1.35 0.55%80 54 1.34 1.53 0.67%90 62 1.45 1.71 0.83%100 70 1.57 1.88 2.22%





A-18 padi.com



10 -6 0.66 0.40 0.17%15 -3 0.74 0.55 0.22%20 0 0.82 0.69 0.28%30 6 0.97 0.96 0.33%40 12 1.13 1.21 0.48%50 18 1.28 1.45 0.55%60 25 1.44 1.68 0.83%70 31 1.59 1.91 2.22%


10 -7 0.68 0.42 0.17%15 -4 0.76 0.57 0.22%20 -1 0.84 0.72 0.28%30 5 0.99 0.99 0.33%40 11 1.15 1.24 0.48%50 17 1.31 1.49 0.67%60 24 1.47 1.73 0.83%


10 -5 0.64 0.34 0.17%15 -2 0.71 0.49 0.22%20 1 0.79 0.63 0.22%30 8 0.94 0.89 0.33%40 14 1.08 1.14 0.42%50 21 1.23 1.37 0.55%60 27 1.38 1.60 0.67%70 33 1.53 1.82 2.22%


10 -6 0.65 0.37 0.17%15 -3 0.73 0.52 0.22%20 1 0.80 0.66 0.22%30 7 0.95 0.92 0.33%40 13 1.11 1.17 0.48%50 20 1.26 1.41 0.55%60 26 1.41 1.64 0.83%70 32 1.56 1.87 2.22%


10 -4 0.61 0.29 0.17%15 -1 0.68 0.44 0.17%20 3 0.75 0.57 0.22%30 9 0.90 0.83 0.28%40 16 1.04 1.07 0.42%50 23 1.18 1.29 0.48%60 29 1.32 1.51 0.67%70 36 1.47 1.73 0.83%80 43 1.61 1.94 2.22%


10 -5 0.63 0.32 0.17%15 -1 0.70 0.46 0.17%20 2 0.77 0.60 0.22%30 8 0.92 0.86 0.33%40 15 1.06 1.10 0.42%50 22 1.21 1.33 0.55%60 28 1.35 1.56 0.67%70 35 1.50 1.78 0.83%


10 -3 0.59 0.23 0.14%15 0 0.65 0.38 0.17%20 4 0.72 0.51 0.22%30 11 0.86 0.76 0.28%40 18 1.00 0.99 0.33%50 25 1.13 1.21 0.48%60 32 1.27 1.43 0.55%70 39 1.40 1.64 0.67%80 46 1.54 1.84 2.22%


10 -4 0.60 0.26 0.14%15 0 0.67 0.41 0.17%20 3 0.74 0.54 0.22%30 10 0.88 0.79 0.28%40 17 1.02 1.03 0.42%50 24 1.16 1.25 0.48%60 31 1.30 1.47 0.55%70 37 1.44 1.68 0.83%80 44 1.58 1.89 2.22%



OXYGEN CONTENT 49%


OXYGEN CONTENT 50%


padi.com A-19



10 -11 0.77 0.60 0.22%15 -8 0.86 0.76 0.28%20 -5 0.95 0.91 0.33%30 0 1.13 1.21 0.48%40 5 1.31 1.49 0.67%50 10 1.48 1.75 0.83%


10 -11 0.78 0.62 0.22%15 -9 0.87 0.78 0.28%20 -6 0.96 0.94 0.33%30 -1 1.15 1.24 0.48%40 4 1.33 1.52 0.67%50 9 1.51 1.79 2.22%


10 -10 0.74 0.55 0.22%15 -7 0.83 0.71 0.28%20 -4 0.92 0.86 0.33%30 1 1.09 1.14 0.42%40 7 1.26 1.42 0.55%50 12 1.43 1.68 0.83%60 18 1.61 1.93 2.22%


10 -10 0.76 0.57 0.22%15 -7 0.84 0.73 0.28%20 -5 0.93 0.88 0.33%30 0 1.11 1.18 0.48%40 6 1.28 1.45 0.55%50 11 1.46 1.72 0.83%


10 -9 0.73 0.52 0.22%15 -6 0.81 0.68 0.28%20 -3 0.90 0.83 0.28%30 2 1.07 1.11 0.42%40 8 1.24 1.38 0.55%50 13 1.41 1.64 0.83%60 19 1.58 1.89 2.22%


10 -9 0.72 0.50 0.22%15 -6 0.80 0.65 0.22%20 -3 0.88 0.80 0.28%30 3 1.05 1.08 0.42%40 9 1.22 1.35 0.55%50 14 1.38 1.60 0.67%60 20 1.55 1.85 2.22%


10 -7 0.69 0.45 0.17%15 -4 0.77 0.60 0.22%20 -1 0.85 0.75 0.28%30 4 1.01 1.02 0.42%40 10 1.17 1.28 0.48%50 16 1.33 1.53 0.67%60 22 1.49 1.77 0.83%


10 -8 0.70 0.47 0.17%15 -5 0.79 0.63 0.22%20 -2 0.87 0.77 0.28%30 4 1.03 1.05 0.42%40 10 1.19 1.31 0.48%50 15 1.36 1.57 0.67%60 21 1.52 1.81 2.22%






A-20 padi.com



10 -17 0.91 0.85 0.33%15 -15 1.02 1.03 0.42%20 -13 1.12 1.20 0.48%30 -9 1.34 1.53 0.67%40 -5 1.55 1.85 2.22%


10 -16 0.90 0.83 0.28%15 -14 1.00 1.01 0.33%20 -12 1.11 1.18 0.48%30 -8 1.32 1.50 0.67%40 -4 1.53 1.82 2.22%


10 -15 0.87 0.78 0.28%15 -13 0.97 0.96 0.33%20 -11 1.08 1.12 0.42%30 -7 1.28 1.45 0.55%40 -3 1.48 1.75 0.83%


10 -16 0.89 0.81 0.28%15 -14 0.99 0.98 0.33%20 -12 1.09 1.15 0.42%30 -7 1.30 1.47 0.55%40 -3 1.50 1.78 0.83%


10 -14 0.85 0.74 0.28%15 -12 0.95 0.91 0.33%20 -10 1.04 1.07 0.42%30 -5 1.24 1.39 0.55%40 -1 1.44 1.69 0.83%


10 -14 0.86 0.76 0.28%15 -12 0.96 0.93 0.33%20 -10 1.06 1.10 0.42%30 -6 1.26 1.42 0.55%40 -2 1.46 1.72 0.83%


10 -13 0.82 0.69 0.28%15 -11 0.92 0.86 0.33%20 -8 1.01 1.02 0.42%30 -3 1.20 1.33 0.48%40 1 1.39 1.62 0.67%50 6 1.58 1.90 2.22%


10 -13 0.83 0.72 0.28%15 -11 0.93 0.88 0.33%20 -9 1.03 1.05 0.42%30 -4 1.22 1.36 0.55%40 0 1.42 1.65 0.83%50 5 1.61 1.94 2.22%


10 -12 0.79 0.65 0.22%15 -9 0.89 0.81 0.28%20 -7 0.98 0.97 0.33%30 -2 1.16 1.27 0.48%40 3 1.35 1.55 0.67%50 8 1.53 1.83 2.22%


10 -12 0.81 0.67 0.28%15 -10 0.90 0.83 0.28%20 -8 1.00 0.99 0.33%30 -3 1.18 1.30 0.48%40 2 1.37 1.59 0.67%50 7 1.56 1.86 2.22%







padi.com A-21



10 -22 1.04 1.07 0.42%15 -21 1.16 1.26 0.48%20 -20 1.28 1.45 0.55%30 -17 1.53 1.82 2.22%


10 -22 1.03 1.05 0.42%15 -20 1.15 1.24 0.48%20 -19 1.27 1.43 0.55%30 -16 1.51 1.79 2.22%


10 -20 1.00 1.01 0.33%15 -19 1.12 1.20 0.48%20 -18 1.24 1.38 0.55%30 -15 1.47 1.73 0.83%


10 -21 1.02 1.03 0.42%15 -20 1.13 1.22 0.48%20 -18 1.25 1.40 0.55%30 -15 1.49 1.76 0.83%


10 -20 0.99 0.98 0.33%15 -18 1.11 1.17 0.48%20 -17 1.22 1.35 0.55%30 -14 1.45 1.70 0.83%


10 -19 0.98 0.96 0.33%15 -18 1.09 1.15 0.42%20 -16 1.20 1.33 0.48%30 -13 1.43 1.68 0.83%


10 -18 0.95 0.92 0.33%15 -17 1.06 1.10 0.42%20 -15 1.17 1.28 0.48%30 -11 1.39 1.62 0.67%40 -8 1.61 1.95 2.22%


10 -19 0.96 0.94 0.33%15 -17 1.08 1.13 0.42%20 -16 1.19 1.30 0.48%30 -12 1.41 1.65 0.83%


10 -18 0.94 0.90 0.33%15 -16 1.05 1.08 0.42%20 -14 1.16 1.25 0.48%30 -11 1.37 1.59 0.67%40 -7 1.59 1.91 2.22%


10 -17 0.93 0.87 0.33%15 -15 1.03 1.05 0.42%20 -14 1.14 1.23 0.48%30 -10 1.36 1.56 0.67%40 -6 1.57 1.88 2.22%







A-22 padi.com



10 -28 1.19 1.30 0.48%15 -28 1.32 1.51 0.67%20 -27 1.46 1.72 0.83%


10 -29 1.20 1.32 0.48%15 -28 1.34 1.54 0.67%20 -28 1.48 1.74 0.83%


10 -23 1.07 1.11 0.42%15 -22 1.19 1.31 0.48%20 -21 1.32 1.50 0.67%30 -19 1.57 1.87 2.22%


10 -23 1.06 1.09 0.42%15 -21 1.18 1.29 0.48%20 -20 1.30 1.48 0.55%30 -18 1.55 1.85 2.22%



10 -27 1.16 1.26 0.48%15 -26 1.29 1.47 0.55%20 -26 1.43 1.67 0.83%


10 -28 1.17 1.28 0.48%15 -27 1.31 1.49 0.67%20 -26 1.45 1.70 0.83%


10 -26 1.15 1.24 0.48%15 -26 1.28 1.45 0.55%20 -25 1.41 1.65 0.83%



10 -26 1.13 1.22 0.48%15 -25 1.27 1.42 0.55%20 -24 1.40 1.62 0.67%


10 -25 1.12 1.20 0.48%15 -24 1.25 1.40 0.55%20 -24 1.38 1.60 0.67%

OXYGEN CONTENT 86%


10 -24 1.08 1.13 0.42%15 -23 1.21 1.33 0.55%20 -22 1.33 1.53 0.67%30 -19 1.58 1.90 2.22%


10 -24 1.09 1.15 0.42%15 -23 1.22 1.36 0.55%20 -22 1.35 1.55 0.67%30 -20 1.60 1.93 2.22%



10 -25 1.11 1.18 0.48%15 -24 1.24 1.38 0.55%20 -23 1.37 1.58 0.67%



OXYGEN CONTENT 85%

OXYGEN CONTENT 87%


padi.com A-23



10 -30 1.22 1.36 0.55%15 -29 1.37 1.58 0.67%20 -29 1.51 1.79 2.22%


10 -29 1.21 1.34 0.55%15 -29 1.35 1.56 0.67%20 -28 1.49 1.77 0.83%

OXYGEN CONTENT 94%OXYGEN CONTENT 93%


10 -30 1.24 1.38 0.55%15 -30 1.38 1.60 0.67%20 -30 1.53 1.82 2.22%


10 -31 1.25 1.40 0.55%15 -31 1.40 1.62 0.67%20 -30 1.54 1.84 2.22%


10 -31 1.26 1.42 0.55%15 -31 1.41 1.65 0.83%20 -31 1.56 1.86 2.22%


10 -32 1.28 1.44 0.55%15 -32 1.43 1.67 0.83%20 -32 1.57 1.89 2.22%


10 -32 1.29 1.46 0.55%15 -32 1.44 1.69 0.83%20 -32 1.59 1.91 2.22%


10 -33 1.30 1.48 0.55%15 -33 1.45 1.71 0.83%20 -33 1.61 1.93 2.22%





A-24 padi.com



3 3.0 0.27 –– 0.00%5 5.0 0.32 –– 0.00%6 6.0 0.34 –– 0.00%9 9.0 0.40 –– 0.00%12 12.0 0.46 –– 0.00%15 15.0 0.53 0.08 0.14%18 18.0 0.59 0.24 0.14%21 21.0 0.65 0.37 0.17%24 24.0 0.71 0.49 0.22%27 27.0 0.78 0.61 0.22%30 30.0 0.84 0.73 0.28%33 33.0 0.90 0.84 0.28%36 36.0 0.97 0.94 0.33%39 39.0 1.03 1.05 0.42%42 42.0 1.09 1.15 0.42%45 45.0 1.16 1.25 0.48%48 48.0 1.22 1.35 0.55%51 51.0 1.28 1.45 0.55%54 54.0 1.34 1.54 0.67%57 57.0 1.41 1.64 0.83%



3 2.8 0.29 –– 0.00%5 4.8 0.33 –– 0.00%6 5.8 0.35 –– 0.00%9 8.8 0.42 –– 0.00%12 11.7 0.48 –– 0.00%15 14.7 0.55 0.15 0.14%18 17.6 0.62 0.30 0.17%21 20.6 0.68 0.43 0.17%24 23.6 0.75 0.56 0.22%27 26.5 0.81 0.68 0.28%30 29.5 0.88 0.80 0.28%33 32.5 0.95 0.91 0.33%36 35.4 1.01 1.02 0.42%39 38.4 1.08 1.13 0.42%42 41.3 1.14 1.23 0.48%45 44.3 1.21 1.34 0.55%48 47.3 1.28 1.44 0.55%51 50.2 1.34 1.54 0.67%54 53.2 1.41 1.64 0.83%57 56.2 1.47 1.74 0.83%

OXYGEN CONTENT 22%


3 2.7 0.30 –– 0.00%5 4.6 0.35 –– 0.00%6 5.6 0.37 –– 0.00%9 8.5 0.44 –– 0.00%12 11.4 0.51 0.03 0.14%15 14.4 0.58 0.21 0.14%18 17.3 0.64 0.36 0.17%21 20.2 0.71 0.49 0.22%24 23.1 0.78 0.62 0.22%27 26.1 0.85 0.75 0.28%30 29.0 0.92 0.87 0.33%33 31.9 0.99 0.98 0.33%36 34.8 1.06 1.10 0.42%39 37.8 1.13 1.21 0.48%42 40.7 1.20 1.32 0.48%45 43.6 1.27 1.42 0.55%48 46.5 1.33 1.53 0.67%51 49.5 1.40 1.63 0.67%54 52.4 1.47 1.74 0.83%57 55.3 1.54 1.84 2.22%



3 2.5 0.31 –– 0.00%5 4.4 0.36 –– 0.00%6 5.4 0.38 –– 0.00%9 8.3 0.46 –– 0.00%12 11.2 0.53 0.09 0.14%15 14.1 0.60 0.26 0.14%18 16.9 0.67 0.41 0.17%21 19.8 0.74 0.55 0.22%24 22.7 0.82 0.68 0.28%27 25.6 0.89 0.81 0.28%30 28.5 0.96 0.93 0.33%33 31.4 1.03 1.05 0.42%36 34.3 1.10 1.17 0.42%39 37.1 1.18 1.28 0.48%42 40.0 1.25 1.40 0.55%45 42.9 1.32 1.51 0.67%48 45.8 1.39 1.62 0.67%51 48.7 1.46 1.72 0.83%54 51.6 1.54 1.83 2.22%57 54.5 1.61 1.94 2.22%

OXYGEN CONTENT 24%

EQUIVALENT AIR DEPTH AND OXYGEN MANAGEMENT TABLE – METRIC


padi.com A-25



3 1.8 0.36 –– 0.00%5 3.7 0.42 –– 0.00%6 4.6 0.45 –– 0.00%9 7.3 0.53 0.10 0.14%12 10.1 0.62 0.30 0.17%15 12.8 0.70 0.47 0.17%18 15.5 0.78 0.63 0.22%21 18.3 0.87 0.78 0.28%24 21.0 0.95 0.92 0.33%27 23.7 1.04 1.06 0.42%30 26.5 1.12 1.20 0.48%33 29.2 1.20 1.33 0.48%36 31.9 1.29 1.46 0.55%39 34.7 1.37 1.59 0.67%42 37.4 1.46 1.71 0.83%45 40.1 1.54 1.84 2.22%48 42.9 1.62 1.96 2.22%


3 2.2 0.34 –– 0.00%5 4.1 0.39 –– 0.00%6 5.0 0.42 –– 0.00%9 7.8 0.49 –– 0.00%12 10.6 0.57 0.20 0.14%15 13.4 0.65 0.37 0.17%18 16.2 0.73 0.52 0.22%21 19.0 0.81 0.67 0.28%24 21.8 0.88 0.80 0.28%27 24.7 0.96 0.94 0.33%30 27.5 1.04 1.07 0.42%33 30.3 1.12 1.19 0.48%36 33.1 1.20 1.32 0.48%39 35.9 1.27 1.44 0.55%42 38.7 1.35 1.56 0.67%45 41.5 1.43 1.67 0.83%48 44.3 1.51 1.79 2.22%51 47.1 1.59 1.90 2.22%

OXYGEN CONTENT 26%


3 2.0 0.35 –– 0.00%5 3.9 0.41 –– 0.00%6 4.8 0.43 –– 0.00%9 7.6 0.51 0.05 0.14%12 10.3 0.59 0.25 0.14%15 13.1 0.68 0.42 0.17%18 15.9 0.76 0.57 0.22%21 18.6 0.84 0.72 0.28%24 21.4 0.92 0.86 0.33%27 24.2 1.00 1.00 0.33%30 27.0 1.08 1.13 0.42%33 29.7 1.16 1.26 0.48%36 32.5 1.24 1.39 0.55%39 35.3 1.32 1.51 0.67%42 38.1 1.40 1.63 0.67%45 40.8 1.49 1.76 0.83%48 43.6 1.57 1.87 2.22%



3 2.3 0.33 –– 0.00%5 4.2 0.38 –– 0.00%6 5.2 0.40 –– 0.00%9 8.0 0.48 –– 0.00%12 10.9 0.55 0.15 0.14%15 13.7 0.63 0.32 0.17%18 16.6 0.70 0.47 0.17%21 19.4 0.78 0.61 0.22%24 22.3 0.85 0.74 0.28%27 25.1 0.93 0.87 0.33%30 28.0 1.00 1.00 0.33%33 30.8 1.08 1.12 0.42%36 33.7 1.15 1.24 0.48%39 36.5 1.23 1.36 0.55%42 39.4 1.30 1.48 0.55%45 42.2 1.38 1.59 0.67%48 45.1 1.45 1.70 0.83%51 47.9 1.53 1.81 2.22%54 50.8 1.60 1.92 2.22%

OXYGEN CONTENT 25%


A-26 padi.com



3 1.4 0.40 –– 0.00%5 3.1 0.47 –– 0.00%6 4.0 0.50 –– 0.00%9 6.6 0.59 0.24 0.14%12 9.2 0.68 0.43 0.17%15 11.8 0.78 0.61 0.22%18 14.5 0.87 0.78 0.28%21 17.1 0.96 0.93 0.33%24 19.7 1.05 1.09 0.42%27 22.3 1.15 1.24 0.48%30 24.9 1.24 1.38 0.55%33 27.6 1.33 1.53 0.67%36 30.2 1.43 1.67 0.83%39 32.8 1.52 1.81 2.22%42 35.4 1.61 1.94 2.22%


3 1.2 0.42 –– 0.00%5 2.9 0.48 –– 0.00%6 3.8 0.51 0.05 0.14%9 6.4 0.61 0.28 0.17%12 8.9 0.70 0.48 0.17%15 11.5 0.80 0.65 0.22%18 14.1 0.90 0.82 0.28%21 16.7 0.99 0.99 0.33%24 19.3 1.09 1.14 0.42%27 21.8 1.18 1.30 0.48%30 24.4 1.28 1.45 0.55%33 27.0 1.38 1.59 0.67%36 29.6 1.47 1.74 0.83%39 32.2 1.57 1.88 2.22%

OXYGEN CONTENT 31%


3 1.7 0.38 –– 0.00%5 3.5 0.44 –– 0.00%6 4.4 0.46 –– 0.00%9 7.1 0.55 0.15 0.14%12 9.8 0.64 0.34 0.17%15 12.5 0.73 0.52 0.22%18 15.2 0.81 0.68 0.28%21 17.9 0.90 0.83 0.28%24 20.6 0.99 0.98 0.33%27 23.3 1.07 1.12 0.42%30 25.9 1.16 1.26 0.48%33 28.6 1.25 1.40 0.55%36 31.3 1.33 1.53 0.67%39 34.0 1.42 1.66 0.83%42 36.7 1.51 1.79 2.22%45 39.4 1.60 1.92 2.22%

OXYGEN CONTENT 32%



3 1.5 0.39 –– 0.00%5 3.3 0.45 –– 0.00%6 4.2 0.48 –– 0.00%9 6.8 0.57 0.20 0.14%12 9.5 0.66 0.39 0.17%15 12.2 0.75 0.56 0.22%18 14.8 0.84 0.73 0.28%21 17.5 0.93 0.88 0.33%24 20.1 1.02 1.03 0.42%27 22.8 1.11 1.18 0.48%30 25.4 1.20 1.32 0.48%33 28.1 1.29 1.46 0.55%36 30.8 1.38 1.60 0.67%39 33.4 1.47 1.73 0.83%42 36.1 1.56 1.87 2.22%

OXYGEN CONTENT 30%


padi.com A-27



3 0.5 0.47 –– 0.00%5 2.2 0.54 0.12 0.14%6 3.0 0.58 0.21 0.14%9 5.4 0.68 0.44 0.17%12 7.8 0.79 0.64 0.22%15 10.3 0.90 0.83 0.28%18 12.7 1.01 1.01 0.42%21 15.1 1.12 1.19 0.48%24 17.5 1.22 1.36 0.55%27 20.0 1.33 1.53 0.67%30 22.4 1.44 1.69 0.83%33 24.8 1.55 1.85 2.22%


3 0.7 0.46 –– 0.00%5 2.3 0.53 0.08 0.14%6 3.2 0.56 0.17 0.14%9 5.6 0.67 0.40 0.17%12 8.1 0.77 0.60 0.22%15 10.6 0.88 0.79 0.28%18 13.0 0.98 0.97 0.33%21 15.5 1.09 1.14 0.42%24 18.0 1.19 1.31 0.48%27 20.4 1.30 1.47 0.55%30 22.9 1.40 1.63 0.67%33 25.4 1.51 1.79 2.22%36 27.8 1.61 1.94 2.22%


3 0.9 0.44 –– 0.00%5 2.5 0.51 0.04 0.14%6 3.4 0.54 0.13 0.14%9 5.9 0.65 0.36 0.17%12 8.4 0.75 0.56 0.22%15 10.9 0.85 0.74 0.28%18 13.4 0.95 0.92 0.33%21 15.9 1.05 1.09 0.42%24 18.4 1.16 1.25 0.48%27 20.9 1.26 1.41 0.55%30 23.4 1.36 1.57 0.67%33 25.9 1.46 1.72 0.83%36 28.4 1.56 1.87 2.22%


3 1.0 0.43 –– 0.00%5 2.7 0.50 –– 0.00%6 3.6 0.53 0.09 0.14%9 6.1 0.63 0.32 0.17%12 8.7 0.73 0.52 0.22%15 11.2 0.83 0.70 0.28%18 13.7 0.92 0.87 0.33%21 16.3 1.02 1.04 0.42%24 18.8 1.12 1.20 0.48%27 21.4 1.22 1.36 0.55%30 23.9 1.32 1.51 0.67%33 26.5 1.42 1.66 0.83%36 29.0 1.52 1.80 2.22%39 31.6 1.62 1.95 2.22%

OXYGEN CONTENT 33%


OXYGEN CONTENT 34%


A-28 padi.com



3 0.2 0.49 –– 0.00%5 1.8 0.57 0.20 0.00%6 2.6 0.61 0.28 0.17%9 4.9 0.72 0.51 0.22%12 7.3 0.84 0.72 0.28%15 9.6 0.95 0.92 0.33%18 12.0 1.06 1.11 0.42%21 14.3 1.18 1.29 0.48%24 16.7 1.29 1.46 0.55%27 19.0 1.41 1.64 0.83%30 21.4 1.52 1.81 2.22%


3 0.4 0.48 –– 0.00%5 2.0 0.56 0.16 0.14%6 2.8 0.59 0.25 0.14%9 5.2 0.70 0.47 0.17%12 7.5 0.81 0.68 0.28%15 9.9 0.93 0.87 0.33%18 12.3 1.04 1.06 0.42%21 14.7 1.15 1.24 0.48%24 17.1 1.26 1.41 0.55%27 19.5 1.37 1.58 0.67%30 21.9 1.48 1.75 0.83%33 24.3 1.59 1.91 2.22%



3 -0.5 0.55 0.14 0.14%5 1.0 0.63 0.33 0.17%6 1.7 0.67 0.41 0.17%9 3.9 0.80 0.65 0.22%12 6.2 0.92 0.87 0.33%15 8.4 1.05 1.08 0.42%18 10.6 1.18 1.28 0.48%21 12.8 1.30 1.48 0.55%24 15.0 1.43 1.67 0.83%27 17.2 1.55 1.86 2.22%


3 -0.3 0.53 0.10 0.14%5 1.2 0.62 0.30 0.17%6 1.9 0.66 0.38 0.17%9 4.2 0.78 0.62 0.22%12 6.4 0.90 0.83 0.28%15 8.7 1.03 1.04 0.42%18 10.9 1.15 1.24 0.48%21 13.2 1.27 1.43 0.55%24 15.4 1.39 1.62 0.67%27 17.6 1.52 1.80 2.22%


3 -0.1 0.52 0.07 0.14%5 1.4 0.60 0.26 0.14%6 2.2 0.64 0.35 0.17%9 4.4 0.76 0.58 0.22%12 6.7 0.88 0.80 0.28%15 9.0 1.00 1.00 0.33%18 11.3 1.12 1.20 0.48%21 13.5 1.24 1.38 0.55%24 15.8 1.36 1.57 0.67%27 18.1 1.48 1.75 0.83%30 20.4 1.60 1.92 2.22%


3 0.0 0.51 0.03 0.14%5 1.6 0.59 0.23 0.14%6 2.4 0.62 0.31 0.17%9 4.7 0.74 0.55 0.22%12 7.0 0.86 0.76 0.28%15 9.3 0.98 0.96 0.33%18 11.6 1.09 1.15 0.42%21 13.9 1.21 1.34 0.55%24 16.3 1.33 1.52 0.67%27 18.6 1.44 1.69 0.83%30 20.9 1.56 1.87 2.22%




padi.com A-29



3 -0.6 0.56 0.17 0.14%5 0.8 0.65 0.36 0.17%6 1.5 0.69 0.44 0.17%9 3.7 0.82 0.69 0.28%12 5.9 0.95 0.91 0.33%15 8.0 1.08 1.12 0.42%18 10.2 1.20 1.33 0.48%21 12.4 1.33 1.53 0.55%24 14.5 1.46 1.72 0.83%27 16.7 1.59 1.91 2.22%


3 -0.8 0.57 0.20 0.14%5 0.6 0.66 0.39 0.17%6 1.3 0.70 0.48 0.17%9 3.5 0.84 0.72 0.28%12 5.6 0.97 0.95 0.33%15 7.7 1.10 1.16 0.42%18 9.8 1.23 1.37 0.55%21 12.0 1.36 1.57 0.67%24 14.1 1.50 1.77 0.83%



3 -1.3 0.61 0.29 0.17%5 0.1 0.71 0.48 0.22%6 0.7 0.75 0.57 0.22%9 2.7 0.89 0.82 0.28%12 4.8 1.03 1.06 0.42%15 6.8 1.18 1.28 0.48%18 8.8 1.32 1.50 0.67%21 10.8 1.46 1.71 0.83%24 12.8 1.60 1.92 2.22%


3 -1.4 0.62 0.31 0.17%5 -0.1 0.72 0.51 0.22%6 0.5 0.77 0.60 0.22%9 2.5 0.91 0.85 0.33%12 4.5 1.06 1.09 0.42%15 6.5 1.20 1.32 0.48%18 8.4 1.34 1.54 0.67%21 10.4 1.49 1.76 0.83%


3 -0.9 0.59 0.23 0.14%5 0.4 0.68 0.42 0.17%6 1.1 0.72 0.51 0.22%9 3.2 0.86 0.75 0.28%12 5.3 0.99 0.98 0.33%15 7.4 1.13 1.20 0.48%18 9.5 1.26 1.42 0.55%21 11.6 1.40 1.62 0.67%24 13.7 1.53 1.82 2.22%


3 -1.1 0.60 0.26 0.14%5 0.3 0.69 0.45 0.17%6 0.9 0.74 0.54 0.22%9 3.0 0.87 0.79 0.28%12 5.0 1.01 1.02 0.42%15 7.1 1.15 1.24 0.48%18 9.1 1.29 1.46 0.55%21 11.2 1.43 1.67 0.83%24 13.2 1.56 1.87 2.22%




A-30 padi.com



3 -1.9 0.66 0.39 0.17%5 -0.7 0.77 0.59 0.22%6 -0.1 0.82 0.68 0.28%9 1.8 0.97 0.95 0.33%12 3.6 1.12 1.20 0.48%15 5.5 1.28 1.44 0.55%18 7.4 1.43 1.67 0.83%21 9.2 1.58 1.90 2.22%


3 -2.1 0.68 0.42 0.17%5 -0.9 0.78 0.62 0.22%6 -0.3 0.83 0.71 0.28%9 1.5 0.99 0.98 0.33%12 3.4 1.14 1.23 0.48%15 5.2 1.30 1.48 0.55%18 7.0 1.46 1.71 0.83%21 8.8 1.61 1.94 2.22%


3 -1.6 0.64 0.34 0.17%5 -0.3 0.74 0.53 0.22%6 0.3 0.78 0.63 0.22%9 2.3 0.93 0.88 0.33%12 4.2 1.08 1.13 0.42%15 6.1 1.23 1.36 0.55%18 8.1 1.37 1.59 0.67%21 10.0 1.52 1.81 2.22%


3 -1.8 0.65 0.37 0.17%5 -0.5 0.75 0.56 0.22%6 0.1 0.80 0.65 0.22%9 2.0 0.95 0.92 0.33%12 3.9 1.10 1.16 0.42%15 5.8 1.25 1.40 0.55%18 7.7 1.40 1.63 0.67%21 9.6 1.55 1.85 2.22%

OXYGEN CONTENT 49%


OXYGEN CONTENT 50%


3 -2.8 0.73 0.52 0.22%5 -1.6 0.84 0.73 0.28%6 -1.1 0.90 0.82 0.28%9 0.6 1.06 1.11 0.42%12 2.3 1.23 1.37 0.55%15 3.9 1.40 1.63 0.67%18 5.6 1.57 1.88 2.22%


3 -2.6 0.72 0.50 0.22%5 -1.5 0.83 0.70 0.28%6 -0.9 0.88 0.80 0.28%9 0.8 1.05 1.07 0.42%12 2.5 1.21 1.34 0.55%15 4.2 1.38 1.59 0.67%18 5.9 1.54 1.84 2.22%


3 -2.3 0.69 0.45 0.17%5 -1.1 0.80 0.65 0.22%6 -0.5 0.85 0.74 0.28%9 1.3 1.01 1.01 0.42%12 3.1 1.17 1.27 0.48%15 4.9 1.33 1.52 0.67%18 6.7 1.48 1.75 0.83%


3 -2.4 0.70 0.47 0.17%5 -1.3 0.81 0.67 0.28%6 -0.7 0.86 0.77 0.28%9 1.1 1.03 1.04 0.42%12 2.8 1.19 1.30 0.48%15 4.6 1.35 1.55 0.67%18 6.3 1.51 1.80 2.22%




padi.com A-31



3 -3.9 0.82 0.69 0.28%5 -3.0 0.95 0.91 0.33%6 -2.5 1.01 1.01 0.42%9 -1.1 1.20 1.32 0.48%12 0.3 1.39 1.61 0.67%15 1.7 1.58 1.89 2.22%


3 -4.1 0.83 0.71 0.28%5 -3.2 0.96 0.93 0.33%6 -2.7 1.02 1.04 0.42%9 -1.3 1.22 1.35 0.55%12 0.0 1.41 1.64 0.83%15 1.4 1.60 1.92 2.22%


3 -3.6 0.79 0.64 0.22%5 -2.6 0.92 0.86 0.33%6 -2.1 0.98 0.96 0.33%9 -0.6 1.16 1.26 0.48%12 0.9 1.34 1.54 0.67%15 2.3 1.53 1.81 2.22%


3 -3.7 0.81 0.67 0.28%5 -2.8 0.93 0.88 0.33%6 -2.3 0.99 0.99 0.33%9 -0.9 1.18 1.29 0.48%12 0.6 1.36 1.57 0.67%15 2.0 1.55 1.85 2.22%




3 -3.3 0.77 0.59 0.22%5 -2.2 0.89 0.80 0.28%6 -1.7 0.94 0.91 0.33%9 -0.1 1.12 1.20 0.48%12 1.4 1.30 1.47 0.55%15 3.0 1.48 1.74 0.83%


3 -3.4 0.78 0.62 0.22%5 -2.4 0.90 0.83 0.28%6 -1.9 0.96 0.93 0.33%9 -0.4 1.14 1.23 0.48%12 1.1 1.32 1.51 0.67%15 2.7 1.50 1.78 0.83%


3 -2.9 0.74 0.55 0.22%5 -1.8 0.86 0.75 0.28%6 -1.3 0.91 0.85 0.33%9 0.3 1.08 1.14 0.42%12 2.0 1.25 1.41 0.55%15 3.6 1.43 1.67 0.83%18 5.2 1.60 1.92 2.22%


3 -3.1 0.75 0.57 0.22%5 -2.0 0.87 0.78 0.28%6 -1.5 0.93 0.88 0.33%9 0.1 1.10 1.17 0.42%12 1.7 1.28 1.44 0.55%15 3.3 1.45 1.70 0.83%18 4.9 1.62 1.96 2.22%

OXYGEN CONTENT 59%


OXYGEN CONTENT 60%


A-32 padi.com



padi.com A-33



A-34 padi.com



padi.com A-35



A-36 padi.com



padi.com A-37



A-38 padi.com



padi.com A-39


IndependentStudyAssignmentswithKnowledgeReviewAnswerKeys See page A-95 for independent study assignments with blank Knowledge Reviews to hand out to students. See the instructor guides for required presentations. In the Tec 40 course, see the notes relating to Other Delivery Content, Tec 40-2, and Tec 45, Knowledge Development One, II. Equipment about the appropriate study assignments for the equip-ment your students will use in the course.

Tec40Tec40KnowledgeDevelopmentOneManual Supported Content

Study assignment: Tec Deep Diver Manual, pgs xi, pg xiii Your Obligations and Responsibilities, pg xiv Diver Accident Insurance, pg 1-9 including Tec Exercise 1.1. Disregard Tec Deep and Apprentice Tec Diver Certification Limits discussions. You may skip question 6 in the exercise.

Other Delivery Content, Tec 40-1Study assignment: Tec 40 Handout 1


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 84-87, Oxygen Compatibility Review, Manufacturer Warranties and Hyperoxic Gases

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 35-50, Gas Planning I, Tec Exercise 1.3


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 51-54, Team Diving I, Tec Exercise 1.4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 54-59, Techniques and Procedures I, Tec Exercise 1.5, pgs 107-109, Team Diving Gas Handling Considerations, Tec Exercise 2.4 questions 4-8, pgs 115-122, Techniques and Procedures III, Tec Exercise 2.5

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 60-64, Emergency Procedures I, Tec Exercise 1.6, pgs 123-129, Emergency Procedures II, Tec Exercise 2.6


A-40 padi.com


Tec40KnowledgeReviewOne Please complete this review to hand in to your instructor. If there’s something you don’t understand, review the related material. If you still don’t understand, be sure to have your instructor explain it to you.

1. Define “recreational diving”, “technical diving”, and explain what is not technical diving.

Recreational Diving is no-stop diving with air or enriched air to a depth no deeper

than 40 metres/130 feet, and in limited overhead environments within 40 linear

metres/130 linear feet of the surface. Typically, this means using relatively simple

equipment (single tank, regulator etc.)

Technical diving is diving beyond recreational limits. Typically this means decom-

pression stop diving, overhead environments, using more extensive technologies and

more complicated equipment configurations (double tanks, independent regulators etc.).

Technical diving is not simply exceeding the limits of recreational diving.

2. List six general risks and hazards that technical diving presents that either don’t exist or aren’t as severe in recreational diving.

No direct access to the surface in an emergency due to deco requirements etc.

Hypoxia/hyperoxia resulting from switching to wrong gas which can lead to drowning.

Narcosis which can lead to poor judgment/bad decisions that can cause an accident.

DCS due to improper gas analysis, missed deco stops, loss of deco gas which can

lead to permanent injury or death.

Omitted procedures due to task loading which can lead to accidents, DCS, air

embolism, oxygen toxicity or drowning.

Drowning /air embolism due to BCD failure.

3. What single statement sums up the difference between recreational and technical diving?

In technical diving, even if you do everything right, there is still a higher inherent

potential for an accident leading to permanent injury and death.

4. What are the goals of the Tec 40 course?

To qualify you to make limited decompression dives at a level that borders between

recreational diving and technical diving.

To train you in the knowledge, procedures and motor skills required for decompres-

sion diving within the limitations of the Tec 40 certification.


padi.com A-41


To assure you understand and acknowledge the hazards and risks associated with

this level of tec diving, and tec diving in general.

To train you to prepare for and respond to reasonably foreseeable emergencies that

may occur within Tec 40 limits.

To lay the foundation continuing your training as a full technical diver in the Tec 45

and Tec 50 courses.

5. What are the limits of the Tec 40 certification?

Dive to a maximum depth of 40 metres/130 feet using air or enriched air.

Make dives with up to 10 minutes required decompression.

Switch during decompression to enriched air nitrox with up to 50 percent oxygen

(EANx50) to make your decompression more conservative.

Although your certification qualifies you to these limits, you must also consider other

limitations, such as the environment, conditions and other factors, and apply more

conservative limits when planning dives.

These limits apply, even if you complete the Tec 40 using double cylinders and other

equipment required for Tec 45 and above.

6. What are the six characteristics of a responsible technical diver:

Self-sufficient. The diver plans and executes each dive as though having to handle

all emergencies alone, and doesn’t rely on any other diver for safety or knowledge.

Team player. The diver is part of the dive team (not just a buddy – more about this

shortly), and contributes as a team player on a team effort.

Disciplined. The diver doesn’t cut corners, bend rules, disregard dive plans, omit

safety equipment or exceed training or equipment limits.

Wary. The diver assumes that everything can and will go wrong on a dive, and

plans contingencies for when it happens.

Physically fit. The diver exercises regularly, eats properly and consults a physician

regularly to maintain the fitness level required for the specific dives the diver makes.

Accepts Responsibility. The diver accepts responsibility for personal safety and

accepts and acknowledges the risks and demands of technical diving.

7. What should you do if you can’t or won’t accept the risks and responsibilities demanded by technical diving?

If you won’t, don’t technical dive.


A-42 padi.com


8. Describe the proper types, number, location and configuration within your rig of the following equipment components as to how your gear will look when worn.

Valves & Cylinders:

The cylinder should have an H or Y valve, which allows you to have two entirely

separate regulators. In case of a failure, you can shut down the gas to either one

and still access the remaining gas with the other. With Tec 40 limits, it is alterna-

tively acceptable to have a large, main cylinder with a pony bottle mounted on the

diver’s left in place of an H/Y valve. While yoke connections are still common, DIN

(Deutches Industrie Norm) is preferred.

Right Regulator accessories:

The right regulator (post behind right shoulder with back mounted doubles on) sup-

ports the primary second stage on a 2 metre/7 foot hose and the LPI for the BCD. If

using a pony bottle, it also has the primary SPG.

Left Regulator accessories:

The left regulator (post behind left shoulder with back mounted doubles) supports

the alternate second stage stowed underneath the chin on a bungee necklace. In

addition, it supports the SPG clipped to the harness and the LPl for back up BCD

and/or drysuit. If using a pony bottle, the SPG is clipped behind the diver or

secured in some way to make it clearly distinguishable from the primary SPG.

BCD and harness:

Most BCDs with shoulder and hip D-rings (other suitable attachment hardware in

those locations) can be used for a Tec 40 rig. The D-rings are necessary for your

decompression cylinder. The tec harness is recommended because you will use it

when you move on to the Tec 45 course, and because you can use a double

bladder BCD

Instruments:

Basic deep technical kit instruments include an SPG (mounted as described above),

compass, dive computer or timer/depth gauge and back up computer or timer/depth

gauge. The compass is typically carried in a pouch or pocket. The computers/depth

gauges may be mounted on one or both arms.

Note: SPGs are of the mechanical type. Few technical divers use air integrated

SPGs to eliminate battery concerns. It is the one instrument that you do not have a

back up for.


padi.com A-43


Cutting tools:

Technical divers carry two small knives or a Z knife and small knife. Cutting shears

may also be used as a cutting tool. The cutting tool is not worn on the leg to avoid

entanglement. Typical locations for cutting tools are on the waist strap, in a pouch

or pocket or on the shoulder strap. Both cutting tools should be sharp and in good

condition. Each cutting tool should be located where the diver can access it with

both hands.

Pockets:

A common and useful pocket in tec diving is the outside thigh pocket located on

your exposure suit. Tec divers may also have a small pouch located on the waist

band of the harness.

Clips:

Used extensively in tec diving. May be brass or stainless steel. They should be the

“sliding gate” type and not “swing gate clips”. The clip should also be large

enough so that they are easy to open and close, but no so large they may cause

entanglements or cause equipment to hang out/down to far. Breakaway clips should

be used on the primary second stage or any other equipment that may need to

accessed quickly in an emergency.

9. List the three types of dive computer you can use for technical deep diving with air and enriched air, along with the advantages and disadvantages of each.

Standard Air Computer:

Advantages - simple, inexpensive and always yields a more conservative decom-

pression profile when using EANx blends of 22% or higher.

Disadvantages – limited in performance (information they provide and flexibility),

can not be used to extend no-stop limits, can not shorten deco stops and they do not

track 02 exposure.

Enriched Air Computers:

Advantages - permit the diver to set for a single EANx blend usually up to 40 or 50

percent O2 content, can extend no-stop times, shorten deco stops using EANx and

are still relatively inexpensive.

Disadvantages - cost more than air computers, limited in performance (info they

provide and flexibility) in comparison with multigas computers and they can not

track your O2 exposure if you switch to a higher blend of EANx during the dive.


A-44 padi.com


Multigas Computers:

Advantages - permit the diver to set for multiple EANx blends for the dive, diver

can change settings on the fly and calculate new extended no-stop times and

deco stops and will track your O2 exposure throughout the dive on two or more

blends of EANx.

Disadvantages –costly and more complicated to use (more possibility of error).

10. What are the recommended maximum oxygen partial pressures for technical deep diving?

1.4 working part of the dive 1.6 at rest (deco stops as long as you are not exerting

yourself).

11. Using the maximum depth formulas, what are the maximum depths and decom-pression depths for EANx48?

Metric: Working (1.4) depth = 19 metres

X = (14/.48) - 10 X = 19.2

Decompression (1.6) depth = 23 metres

X = (16/.48) - 10 X = 23.3

Imperial: Working (1.4) depth = 63 feet

X=(46.2/.48)-33 X=63.2

Decompression (1.6) depth = 100 feet

X = (52.8/.48) - 33 X = 100

(Metric) if your SAC rate is 24 litres/min, how much gas volume do you need for 20 minutes at 30 metres? What would your total volume be with a reserve based on the rule of thirds?

20 x (24 x 4.0) = 1920 Dive time x (SAC x depth conversion)

1920 x 1.5 = 2880 Volume needed at depth x 1.5

(Imperial) if you SAC rate is .8 cubic feet/min, how much gas volume do you need for 20 minutes at 90 feet? What would your total volume be with a reserve based on the rule of thirds?

20 x (. 8 x 3.7) = 59.2cf Dive time x (SAC x depth conversion)

59.2 x 1.5 = 88.8 Volume needed at depth x 1.5


padi.com A-45


12. What are the signs and symptoms of CNS oxygen toxicity, and what’s the primary way you avoid it?

VENTID

V - Visual disturbance

E - Ears, ringing in the ears or other sounds

N - Nausea

T - Twitching around the face

I - Irritability

D - Dizziness

The primary way you avoid CNS toxicity is to stay within the working (1.4) and

decompression/safely stops (1.6) PO2 limits.

13. What are the signs and symptoms of pulmonary oxygen toxicity, and what is the primary way to avoid it?

Signs/Symptoms: irritation, burning sensation in the chest, coughing, reduced vital

capacity. The primary way to avoid pulmonary oxygen toxicity is to manage and

monitor your oxygen exposure and keep it within computer/table limits.

14. List your responsibilities as a team member when technical diving.

Be self sufficient, even in an emergency.

Don’t let the team carry you beyond your limits.

Watch your team mates as closely as you watch yourself

When necessary, surrender your individual preferences to team needs.

Don’t exert peer pressure and do not succumb to peer pressure.

15. What is the rule regarding aborting a technical dive?

Any diver can abort any dive at any time for any reason.

16. What is the primary hazard of diving negatively buoyant, and how do you manage this hazard?

The primary hazard of negative buoyancy is having a BCD failure make it impossi-

ble to ascend due to the weight of the equipment. Negative buoyancy is managed by

having a back up BCD.

This may be another BCD (dual bladder) or using a dry suit if you are diving one.


A-46 padi.com


17. What is the primary hazard of excessive positive buoyancy, and how do you man-age this hazard?

The primary hazard is that you may not be able to make a required decompression

stop and/or have an uncontrolled ascent leading to a high risk of DCI. Positive

buoyancy is managed/avoided by checking your weight system during your predive

check, wearing dual buckles on your weight belt (if using one) and checking/deter-

mining your weight requirements with near empty cylinders.

18. Describe how to find the minimum weight and the minimum buoyancy you need for a technical deep dive.

Minimum Weight: Technical divers should weight themselves for the worst-case sce-

nario (due to an emergency, you have used up nearly all your gas, which may weigh

up to 7kg/15lbs or more). Therefore technical divers should weight themselves to be

neutrally buoyant with nearly empty(34 bar/500psi or less) cylinders and no stage/

deco cylinder.

Minimum Buoyancy: Technical divers need sufficient buoyancy to float with their

heads comfortably above the surface while wearing full doubles and full stage/

decompression bottles. One BCD bladder should be able to accomplish this without

using the second or back up BCD and or dry suit:

19. How does a technical dive in a dry suit differ from a recreational dive in a dry suit? What’s the recommended number of recreational dives in a dry suit that you should have before technical diving in one?

In recreational diving, using the dry suit to control buoyancy is the preferred meth-

od of controlling buoyancy, however on a tec dive, the technical diver should only

add just enough gas to avoid suit squeeze. This avoids an uncontrolled ascent when

ascending. Technical divers must therefore adjust the gas in both the dry suit and

the BCD during a tec dive. Adding too much air to the dry suit is one more poten-

tial hazard for the technical diver. In addition, dry suits add an additional hose to

the technical kit and affects body control and buoyancy underwater. You should

have at least 20 dives in the suit before attempting a tec dive or whatever it takes to

feel comfortable in using the suit with a tec kit.


padi.com A-47


20. Describe the procedure for sharing gas with your long hose.

Out of gas diver signals, “out of gas.”

The donor passes the second stage from the mouth to the receiver, unlooping the

hose from over the head with an arm twist while doing so. The donor then switches

to the short hose secondary hanging from the neck. If the hose is clipped off

(during a deco stop), the donor jerks it off the breakaway clip and stays on the

stage/deco cylinder.

Abort the dive.

21. What are the emergency procedures for a massive regulator (second stage) free flow at depth?

Breathe from unaffected regulator.

Reach behind and close the valve to the free flowing regulator.

Abort the dive.

22. What are the emergency procedures for a damaged doubles manifold at depth?

Reach back and close the isolator valve.

Try to determine which side is leaking. lf you can’t see where the bubbles are

coming from, check your SPG. If it is dropping rapidly, the leak is on the left side.

If not, it is on right.

Abort the dive breathing from the leaking side to take advantage of what gas

remains, and switch to the conserved side when the gas runs out of the leaking side.

23. What is the over-riding mission of all technical dives?

Return with your team mates alive and uninjured.

24. How and why does “cutting corners” lead to accidents in technical diving?

It creates a potential hazard for the diver or the potential for an error. Given that in

technical diving the error chain to an accident is significantly shorter than in recre-

ational diving, cutting corners has a high risk of causing or starting a chain of

errors that lead to an incident or emergency.


A-48 padi.com



padi.com A-49


Tec40KnowledgeDevelopmentTwoManual Supported Content

Study assignment: Tec Deep Diver Manual, pgs 64-64, Thinking Like a Technical Diver I, Tec Exercise 1.7

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 88-93 Introduction to Decompression Stop and Gas Switch, Extended No Stop Diving, Equivalent Air Depths (Continued) and Equivalent Narcotic Depths, Ideal Enriched Air for a Particular Depth, Determining Gas Supply and Reserve Requirements for Multiple Depths and Decompression stops (first page only); pgs 97-99 Desk Top Decompression Software Tec Exercise 2.2, Questions 1-8 & 10. Pg 157 down to “Example” on pg 158, Planning a Decompression Dive Using a Single Gas Computer.



Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 101-107, Thinking Like a Technical Diver II, Team Diving II, Tec Exercise 2.3, pgs 109-113, Predive Check, Technical Diving Hand Signals, Tec Exercise 2.4, questions 1-3 and 9-15.

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 167, When to Make Cylinder Switches, pgs 162-166, Emergencies III, Tec Exercise 3.3

Tec40KnowledgeReviewTwo Please complete this review to hand in to your instructor. If there’s something you don’t understand, review the related material. If you still don’t understand, be sure to have your instructor explain it to you.

1. Describe a suitable, rigged stage deco bottle “package.”

The typical stage/deco cylinder has a nylon rope or strap approximately 46cm/18 in

(more or less to individual needs) running from under the valve opening or knob

down to a band around the cylinder, with a clip at each end. The regulator attached

has only a second stage with a breakaway mount clip and an SPG attached to the

first stage. The mouth piece may have a cover or block.

The cylinder should have at least two bands (bungee or inner tubing) to hold the


A-50 padi.com


second stage and SPG (if it is not on a short hose) hoses securely against the cylinder. The

nylon strap/rope may also have plastic tubing around it that serves as a handle when han-

dling the cylinder above and underwater.

2. Briefly list the guidelines regarding material and equipment compatibility using enriched air and oxygen. What do you risk if you fail to follow these guidelines?

When using blends of 41 percent oxygen or higher all equipment that comes in contact

with the gas must be rated for oxygen service. Oxygen service means the equipment is

oxygen clean - free of contaminants and made of materials that will not combust when in

contact with higher percentages of O2.

Manufacturer’s Recommendations: In general, for blends of 40 percent or less the equip-

ment does not need to be rated for oxygen service; however you should check with the

manufacturer of the equipment and/or local law and follow any requirements or guide-

lines listed for the equipment you will be using

Maintain O2 Clean: Do not expose oxygen clean equipment to air fills that will void the

oxygen clean service rating or to other contaminants.

Markings /Decals: Leave EANx cylinder decals in place after diving.

Fill Slowly: Fill all cylinders slowly and open and close all valves slowly to minimize

heating and cooling from compression and decompression of the gas.

Protect From Contamination: Keep O2 clean equipment away from contaminants like oils,

exhaust fumes etc. Bag equipment when possible and rinse and store as soon as possible

after use.

Re-clean Annually: Have equipment O2 cleaned annually.

Not following these guidelines can result in fire or explosion.

3. Explain how you determine your required decompression stops using a single gas com-puter or table, and how to use switches to enriched air or oxygen to make the decompres-sion more conservative.

You plan the dive as if you will use air (or EANx you will use on the bottom) for the entire

dive, including decompression. Use desktop decompression software to generate tables

based on using a single gas, or to estimate the required stops your dive computer will give.

During the dive, follow the table, or your computer set for air or the bottom EANx. Follow

the decompression schedule, but you can switch to EANx or oxygen (as a Tec 45 diver or

higher) to make your decompression more conservative.


padi.com A-51


4. What do you assume your END is with enriched air? Why?

The END with EANx is the same as air. Oxygen is probably just as narcotic as

nitrogen (possibly more so). Given that very little oxygen in each breath is metabo-

lized or otherwise consumed by the body, you assume your END does not change.

5. What are the advantages and risks of using desk top decompression software?

Advantages:

Generates custom tables for the dive

Can generate contingency tables if time/depth is exceeded

Saves time

Avoids human calculation errors

Allows for easy modification of the dive profile (depth, time gas blend etc.)

Can be generated at the dive site with a laptop computer

Calculates 02 exposure along with gas consumption and N2 tracking

Disadvantages/risks:

Because people vary in their physiology, no software, dive computer or table can

guarantee that DCS or oxygen toxicity will never occur even within the limits they

provide. Extremely long dives, dives involving gases other than oxygen and nitro-

gen, and dives with reverse profiles may carry a risk of being experimental because

they may they take you outside the body of established test data.

6. What should you assume about every technical dive, and what should you take for granted?

Murphy’s law: Anything that can go wrong, will go wrong. You should take nothing

for granted.

7. What is your most important resource in a tec diving emergency, and what provides this resource?

Your most important resource in a tec diving emergency is time. Your reserve pro-

vide this resource.

8. What is the principle of your gas reserve?

At the end of the dive, if you had no emergency, you should still have all of the

reserve left in all your cylinder(s).


A-52 padi.com


9. What is the recall phrase for the seven segments of planning a tec dive, and what does the phrase stand for?

A Good Diver’s Main Objective Is To Live

Good - Gas management

Divers - Decompression

Main - Mission

Objective - Oxygen

Is – Inert gas narcosis

To - Thermal considerations

Live – Logistics

10. Why do all team members on a technical dive usually use the same gases?

Allows team members to share gas in an emergency.

Makes observing team members protocols and gas use easier.

Reduces confusion.

Helps to keep the team together since they must follow the same protocols, sched-

ules and limits you do.

11. What four markings should be on every cylinder used on a technical dive? Which should be easy to read by all team members while worn? Why are these markings required?

Color coding - Makes it easy to determine if the gas is air, oxygen or enriched air.

Maximum depth – Important in avoiding hyperoxia, which may lead to convulsions/

drowning.

This should be easy to read by all team members.

Name - This is essential in avoiding picking up the wrong gas. While tec divers

strive to use the same gases throughout the dive, there may be times when there may

be differences between team members. Breathing the wrong gas will affect your

deco stops and can lead to DCl, hypoxia, hyperoxia. This should be easy to read by

all team members.

Other markings - Content stickers, warnings to other divers not to remove etc.


padi.com A-53


12. Who must check the pressure and oxygen analysis of every cylinder used for a technical dive?

The diver who will be using the cylinder.

13. What is the predive check recall phrase in tec diving? What does it stand for, and what steps does the predive check include? Being Wary Reduces All Failures.

Being: BCD. Confirm connection and proper operation of both BCDs.

Wary: Weight. Confirm weight is properly secured and/or that ample buoyancy and

back up buoyancy is available if the diver is heavy.

Reduces: Releases. Confirm all releases are secure and intact and that stage/deco

bottles can be cut away in case of an emergency.

All: Air. Confirm all manifold valves are open, test breathe regulators, confirm that

the long hose is not trapped, confirm turn pressure.

Failures: Final check-head to toe check for loose or missing gear may include bub-

ble check and/or descent check.

14. What is your turn pressure if you have 190 bar or 2800 psi in your cylinders and your are using a reserve of one-third?

(Metric): 130 (Imperial): 1900

190 rounds down to 180/3 = 60 2800 rounds down to 2700/3 = 900

190 - 60 = 130 2800 - 900 = 1900

15. Describe how to perform a bubble check and a descent check.

Bubble Check: Each diver leans back to submerge the valves underwater and a

team mate checks the valves, regulators, SPG, stage/deco valves and regulators for

bubbles. In some instances, it may be necessary to descend deeper (rough surface

conditions etc) to perform the check.

Descent Check: When feasible, this is done at the level of the shallowest deco stop.

Team mates do a final check of equipment looking for loose gear, trapped hoses;

insure the stage bottles are secure and that everyone is breathing the correct gas.


A-54 padi.com


16. The thumbs up means______ ___ ____ _____ ____ ___ .

End the dive now (command signal).

17. What is the ideal position and stop depth level when decompressing? What is the most important skill you need for decompressing?

Ideally, divers should be in a horizontal position, with stop depth at mid chest.

Buoyancy and the ability to maintain depth for an extended period is the most

important skill you need for decompressing.

Student Diver statement: I’ve reviewed the questions I answered incorrectly or incompletely and I now understand what I missed.

Signature _________________________________________ Date ________________


padi.com A-55


Tec40KnowledgeDevelopmentThreeOther Delivery Content, Tec 40-6

Study assignment: Tec 40 Handout 6


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 204, sidebar, How Do I Figure 1.5 Times with a Computer?

Tec40KnowledgeReviewThree Please complete this review to hand in to your instructor. If there’s something you don’t understand, review the related material. If you still don’t understand, be sure to have your instructor explain it to you.

1. What is one of the most common preventable causes of death in technical diving?

Oxygen toxicity caused by switching to the wrong gas at depth -- too high oxygen for

the depth.

2. What is the recall acronym for gas switches? Describe the gas switch procedure and how the acronym prompts you.

NO TOX

N - Note your name and the maximum depth on the cylinder.

O - Observe the actual depth on your computer/depth gauge and compare it to the

max depth on the cylinder label.

T - Turn open the valve and check the cylinder pressure.

O - Orient the second stage (deploy hose, remove mouthblock if there is one, etc.)

for breathing.

X - Examine your team mates. Follow the hose from their mouthes to the cylinders

and check the markings on the cylinders and compare them with the actual depth.

3. List five guidelines that reduce the chance of accidentally switching to an unsafe gas blend at depth.

1. When feasible, do not take the cylinder deeper than you can safely breathe from it.

2. Personally, analyze your gas and mark the cylinder accordingly.

3. Block the regulator mouthpieces on cylinders that you can not breathe from safely.


A-56 padi.com


4. Follow the complete gas switch procedure, step by step.

5. Never get complacent.

4. Describe what to do if you experience possible symptoms of CNS oxygen toxicity.

Immediately switch to your back gas (lower O2). lf you are at depth on back gas,

ascend immediately. Check your depth and reconfirm what gas you should be using.

Remain on back gas for at least 5 minutes after all CNS symptoms subside before

returning to your higher oxygen gas. Be sure not to switch back until shallower than

the max depth.

5. What is the “ideal” gas blend for a dive to 25 metres/83 feet?

EANx40

6. What is the general procedure if you can’t return to your planned ascent line?

You can attempt a quick search (time and gas permitting), but the most common

procedure is to deploy a lift bag/DSMB and ascend along the line.

7. How do you learn to account for environmental variables, such as current, visibility, temperature and waves when planning a tec dive?

Get an orientation to the new area and to any special procedures and techniques that

apply to it.

Get the orientation from an experienced local tec diver ideally, a technical diving

instructor.

8. What are four guidelines to consider when planning a tec dive in an unfamiliar environment?

Gain experience with a new environment before making challenging tec dives in it.

Make recreational and/or no-stop dives initially.

Master new, area specific equipment and procedures in controlled conditions before

applying them on more challenging tec dives.

Consult local tec divers. Local methodologies evolve based on local needs; just

because something works well in one environment doesn’t mean that it’s suited

to another.

Recognize the difference between local methods and inappropriate methods.


padi.com A-57


9. What assumption do technical divers make when they plan a dive?

That they may need to complete the dive alone.

10. List six principles for surviving a tec dive.

1. The principle of secondary life support

2, The principle of gas reserve

3, The principle of self sufficiency

4. The principle of depth.

5. The principle of simplicity (KISS)

6. The principle of procedure and discipline

11. As a Tec 40 diver, what should you do if you exceed your planned depth and time?

Immediately ascend and consult your computer. Your allowable dive time will likely

be much shorter than you planned.

If you exceeded your depth significantly and/or for more than a minute, end the dive

immediately.

12. As a Tec 40 diver, what should you do if you omit decompression?

If you can, redescend and complete the stop, plus one minute, then finish decompres-

sion according to your dive computer.

If you can’t redescend, stay at the next stop for the combined time of both stops.

Extend your last two stops (if two or more) by 1.5 times what your computer

requires, and/or as long as you can with the gas you have.

If you computer locks out you should have your planned decompression schedule

with you (on a slate, backup tables, etc.) in case of this kind of emergency.


Signature _________________________________________ Date ________________


A-58 padi.com



padi.com A-59



Study assignment: Tec Deep Diver Manual, pgs 10-33, Equipment I, Tec Exercise 1.2, pgs 80-87, Equipment II, Tec Exercise 2.1, pgs 142-145, Equipment III, Tec Exercise 3.1 Watch the TecRec Equipment Setup and Key Skills video.


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 93-97, Determining Gas Supply and Reserve Requirements for Multiple Depths and Decompression Stops pgs 146 -161, Gas Planning III, Tec Exercise 3.2

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 167-172, Turn Around Points and Environmental Variables, Tec Exercise 3.4, questions 2-4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 173-175, Team Diving III, Tec Exercise 3.5


1. What are the limits of your training as a Tec 45 diver?

To qualify you to make limited decompression dives using air, enriched air and

oxygen to a depth of 45 metres/145 feet or less. Certification as a Tec 45 diver

qualifies you to use a single decompression gas of up to 100 percent oxygen to make

your decompression more conservative or to accelerate your decompression.


A-60 padi.com


2. What are your responsibilities during the Tec 45 course?

a. Follow the instructor’s directions and dive plans strictly, and to not

separate from the instructor or your dive team.

b. To take all aspects of what you’re learning seriously, and to display

an attitude and conduct that is consistent with that expected of team-

oriented technical diver.

c. To refrain from tec diving beyond your previous certification level

outside this course until you’re fully qualified and certified at this

new level.

d. To maintain adequate physical and mental health, and to alert the

instructor to any problems you have with them.

e. To accept the risk for this type of diving, and for specific risks unique

to each dive environment, and to immediately notify the instructor if

this risk becomes intolerable for you.

3. What is meant by “standardized technical rig” and why do you need to apply it?

The technical community has evolved a standardized technical rig that

minimizes and streamlines your gear so that nothing dangles, everything is

easily accessible and so you eliminate the unnecessary.

With the extensive equipment need in technical diving, you must apply the

standardized rig philosophy to minimize confusion and procedural error due

to equipment task loading, and to assure streamlining, which avoids

entanglements and reduces wasted energy due to drag.

4. Describe the proper types, number, location and configuration within your rig of the following equipment components and how your gear will look when worn:

Manifold (if applicable) - a valve with twin regulator posts that can shut

down gas to either regulator and still allow the other access to all gas in

both cylinders (in case of a freeflow malfunction).

It may also have an isolator manifold, which is a valve that separates the

cylinders and saves half the remaining gas in the event of a manifold leak.

DIN (Deutches Industrie Norm) system is preferred over the yoke system. If a

single cylinder is used, valve should be a H or Y configuration, again DIN

preferred over yoke.


padi.com A-61


Right regulator and accessories – Attached to the right post (post behind

divers right shoulder) regulator with a low pressure inflator hose and

a single second stage on a 2m/7’ hose and a LPI hose for primary

BCD inflator.

Sidemount – Attached to right cylinder with a single second stage on a 2m/7’

hose and LPI hose (shorter than backmount) attaches to the back up inflator.

Additional SPG on a short, 5 – 7 cm/2 – 3 inch hose.

Left regulator and accessories – Attached to the left post regulator with the

SPG and a single second stage on a standard length (about 80 cm/32 in)

hose. This regulator will also have your back up BCD/dry suit hose.

Sidemount will be similar, however, with a different hose length low pressure

inflator and LPI attaches to primary BCD.

BCD and harness - The basic deep technical rig calls for a harness that sits

on top of an interchangeable BCD bladder or wings (may be single or dual).

BCD inflator hose located over the left should and retained. Wings may be

bungeed or unbungeed. Back up BCD clipped off or bungeed to the wing.

The harness and wing(s) attaches to double cylinders via recessed wing nuts

that screw down on the cylinder band bolts. The harness should have D

rings at the shoulder and hips for attaching stage cylinders.

In the case of sidemount, the BCD bladder or wings (may be single or dual)

may or may not be incorporated into the fabric harness. BCD inflator hose

located over the left shoulder and retained. Wings may be bungeed or

unbungeed. Back up BCD clipped off or bungeed to the wing. There are no

bands to mount to with sidemount, however, the harness should have D rings

at the shoulder and hips, however, may have a metal rail system at the

bottom and back of the harness to connect the lower part of the main

cylinder and stage cylinders.

Instruments – Basic deep technical rig instrumentation: SPG, compass,

computer or timer/depth gauge and back up computer or timer/ depth gauge.

Technical divers generally arm mount instruments (SPG typically is clipped

to the harness somewhere).


A-62 padi.com


Compass – liquid filled stowed in pocket

SPG – mechanical

Timing Device & Depth Gauge – typically integrated into computer

but may be separate instruments used in conjunction w/ dive tables.

Cutting tools –You always dive with at least two cutting tools. Carry at least

one where you can deploy it with either hand. Examples of cutting tools are:

dive/bosun/Z knife, EMT Shears, multipurpose tool.

Pockets and clips - To minimize confusion and bulk, avoid large pocket

pouches on harness; small pockets for back up gear (e. g. , spare mask) out

of the way at hips okay. Most useful pocket in tec diving is on the outside of

the thigh on exposure suit (some manufacturers make a strap on pocket if

your exposure suit doesn’t have one).

Use brass or stainless steel clips on accessories, SPG, etc. Mount clip on

accessory, not on the BCD. Sliding gate clips (a. k. a. “dog clips”) preferred

by most divers to marine snaps (a. k. a. “swinging gate clips”) because they

won’t accidentally snap on to things by themselves. Use clips for the

environment – smaller clips in warm water (no gloves needed) and larger

clips for cold water. Breakaway clips used for items that need to used quickly

and/or in an emergency.

5. Describe a suitably rigged stage/deco bottle.

The typical stage/deco cylinder has a nylon rope or strap approximately

46cm/18 in (more or less) running from under the valve or knob down to a

band around the cylinder with a brass or stainless steel clip at each end. The

regulator has single second stage with a breakaway clip and an SPG. The

SPG may be on a short or long hose. If on a short hose, the gauge is secured

to the valve. If on a long hose it along with the regulator hose are looped

along the cylinder and secured with bungee or shock cord. The mouthpiece

may or may not have a block on it.


padi.com A-63


6. List three reasons why tec divers consider a slate standard equipment.

Communication

Tracking dive information

Key information/reminders – turn points, max depth, etc.

7. List three types of dive computers you can use for technical diving with air and enriched air, along with the advantages and disadvantages of each.

Standard Air computer

Advantages – inexpensive, easy to use

Disadvantages – for tec diving not effective for deco profiles or must

used in gauge mode, they do not track O2 exposure

Single Gas/Enriched Air computer

Advantages – permit the diver to use different bottom gas,

inexpensive, easy to use.

Disadvantages – do not allow for accelerated deco profiles, will not

track O2 exposure if you switch to higher blend of EANx during the dive.

Multigas Computers

Advantages – permit the diver to use multiple gasses which can be

switched on the fly and track divers O2 exposure.

Disadvantages – more costly and more complicated to use.

8. Name two buoyancy control devices and explain what is meant by “appropriate back up buoyancy. ”

Technical buoyancy compensation device and a dry suit. “Appropriate back

up buoyancy” means a secondary piece of equipment designed for and

commonly used by divers to establish neutral and buoyancy underwater and

positive buoyancy at the surface after the failure of the primary BCD. Note

– in the case of very heavy kit (large capacity steel cylinder, metal backplate

etc), a dry suit may not be able to hold enough gas to support the diver and

would not be a suitable back up in the case of a primary BCD failure.


A-64 padi.com


9. How does a technical dive in dry suit differ from a recreational dive? What is the recom-mended number of recreational dives in a dry suit that you should have before using it on a technical dive?

On a technical dive, the diver should use the BCD and only add enough air to the dry suit

to offset squeeze. This makes it easier and quicker to dump air from the dry suit when the

diver ascends and avoids the situation where the diver would need both hands to dump air

from both the BCD and dry suit. A diver should have at least 20 logged recreational dives

in a dry suit before using one for tec diving.

10. What are four different weighting options for tec diving and list the advantages and dis-advantages of each.

Weight belt, integrated weight system, weight harness and combination.

a. Weight belt

• Advantages: simple, readily available when needed.

• Disadvantages: must don after putting on rig so it’s not trapped by crotch

strap; can be hard to position securely amid other components. Note: Since los-

ing weights on a deco dive can be hazardous (discussed in a moment), some

divers intentionally wear their crotch straps over their weight belts, knowing

they’ll have to release it in weight ditching emergency.

b. Integrated weight system

• Advantages: no need to put on last; prepositioned amid rest of rig

• Disadvantages: must have harness system that accepts one; makes already

heavy rig heavier; may add clutter to configuration (depends on design)

c. Weight harness

• Advantages: put on before rig; does not add to rig’s weight; provides key advan-

tages of both weight belt and weight system

• Disadvantages: may be awkward to adjust and position so that rig doesn’t

interfere with weight ditching; may interfere somewhat with putting rig on.

d. Combination

• Advantages: loss of one weight system doesn’t lose all your weight; may make

configuration and donning easier.

• Disadvantages: more complicated preparation, one more thing to remeber.


padi.com A-65



The primary hazard of negative buoyancy is having a BCD failure making it impossible to

ascend due to the weight of the equipment. Negative buoyancy is managed/avoided by

having a back up BCD. This may be another BCD (dual bladder) or using a dry suit if you

are diving one.

12. List the guidelines regarding material and equipment compatibility using enriched air and oxygen. What do you risk if you fail to follow these guidelines?

In general, for blends of 40% oxygen or less. regulators and other equipment does

not need to be rated for oxygen service, however, not all manufactures follow this

guideline. You should check with the manufacturer of the equipment or check with

local law and follow any guidelines listed for the equipment you will be using.

Above 40%, the equipment needs to be oxygen service rate – both oxygen clean and

oxygen compatible.

Exposing oxyge clean equipment to air fills or other sources of contamination that

will render equipment no longer the oxygen clean.

Equipment should be oxygen cleaned annually or if the equipment has been

exposed to contaminants.

Cylinders and other equipment should have labels in place to inform blender, diver

and other dive team members that they cylinders and other equipment are rated/

cleaned for O2 service.

When filling, fill all cylinders slowly to minimize compression heating. Open valves

to pressurize your regulator slowly for the same reason. Failure to follow these

guidelines could result in a fire or explosion.

13. List four reasons why DSMBs are replacing lift bags in tec diving situations.

1. DSMBs stand higher in the water, making them preferred for rough conditions

and drift decompression.

2. DSMBs are more compact on your rig, making them popular when sending one

up is an emergency alert only.


A-66 padi.com


3. DSMBs have no-spill designs (though several lift bags have these, too,

now), so accidentally losing tension on the line isn’t likely to result in a

spilled buoy.

4. Several types of DSMBs (and lift bags) have LP inflation ports that allow

you to fill away from your body or mouth without using a second stage.

This minimizes the chance of regulator freeze, as well as minimizing reel

tangle issues.

14. (Metric) If your SAC rate is 24 litres/minute, how much gas volume do you need for 20 minutes at 30 metres? What would your total volume be with a reserve based on the rule of thirds?

24 x 20 x 4. 0 = 1920 liters; 1920 x 1.5 = 2880. Diver needs 1920 litres for the

working/bottom part of the dive and 2880 litres total for the rule of thirds.

14. (Imperial) If you SAC rate is . 8 cfm, how much gas volume do you need for 20 min-utes at 90 feet?

.7 x 20 x 4. 0 = 56 cubic feet; 56 x 1.5 = 84 cf. Diver needs 56 cubic feet of

gas for the working/bottom part of the dive and 84 cubic feet total for the rule

of thirds.

15. (Metric) What is your turn pressure for your back gas based on the dive profile information below? Do you have enough back gas to do the dive and return with a one-third reserve?

Cylinders = 17 litres filled to 200 bar Bottom Time = 20 minutes Depth = 44 metres Decompression: 2 minute ascent to deep stop on back gas 2 minutes at 28 metres (deep stop) on back gas 2 minute ascent to first stop on back gas 2 minutes at 12 metres on back gas 4 minutes at 9 metres on EANx 50 4 minutes at 6 metres on Oxygen 12 minutes at 5 metres on Oxygen Working SAC = 18 Deco SAC = 15


padi.com A-67


Doubles volume: 17 x 2 x 200 = 6,800

Bottom volume: 20 x 18 x 5.5 = 1980 Bottom pressure: ( 1980 ÷ 6800) x 200 = 58.24

Ascent to deep stop: 2 x 18 x 4.6 = 165.6 Ascent pressure: (165.6 ÷ 6800) x 200 = 4.87

Deep stop: 2 x 15 x 4.0 = 120 Deep stop pres: (120 ÷ 6800) x 200 = 3.53

Ascent to first stop: 2 x 18 x 3.1 = 111.6 Ascent pressure: (111.6 ÷ 6800) x 200 = 3.28

First stop: 2 x 15 x 2.2 = 66 Stop pressure: (66 ÷ 6800) x 200 = 1.94

Total volume of back gas needed = 2443.2 Total pressure of back gas needed = 71.86

Reserve needed: 6800 ÷ 3 = 2267

Reserve remaining: 6800 – 2443.2 = 4356.8

Is there enough back gas to do the dive? Yes Turn pressure: 200 – 58.24 = 141.76

15. (Imperial) What is your turn pressure for your back gas based on the dive profile information below? Do you have enough back gas to do the dive and return with a one-third reserve?

Cylinders = 108 cf filled to 2400 psi Cylinder Baseline (doubles) = .045 Bottom Time = 20 minutes Depth = 145 feet Decompression: 2 minute ascent to deep stop on back gas 2 minutes at 92.5 feet (deep stop) on back gas 2 minute ascent to first stop on back gas 2 minutes at 40 feet on back gas 4 minutes at 30 feet on EANx 50 4 minutes at 20 feet on Oxygen 12 minutes at 15 feet on Oxygen Working SAC = .64 Deco SAC = .53


A-68 padi.com


Doubles volume = 216cf

Bottom volume: 20 x .64 x 5.5 = 70.4 Bottom pressure: (70.4 ÷ 216) x 2400 = 782.22

Ascent to deep stop: 2 x .64 x 4.6 = 5.89 Ascent pressure: (5.89 ÷ 216) x 2400 = 65.44

Deep stop volume: 2 x .53 x 4.0 = 4.24 Deep stop press: (4.24 ÷ 216) x 2400 = 47.11

Ascent to first stop: 2 x .64 x 3.1 = 3.97 Ascent pressure: (3.97 ÷ 216) x 2400 = 44.11

First stop volume: 2 x .53 x 2.2 = 2.33 Stop pressure: (2.33÷ 216) x 2400 = 25.89

Total volume of back gas needed: = 86.83 Total pressure of back gas needed = 182.55

Reserve needed: 216 ÷ 3 = 72

Reserve remaining: 216 – 86.83 = 129.17

Is there enough back gas to do the dive? Yes Turn pressure: 2400 – 782.22 = 1617.78

16. Explain how you determine your required decompression stops using a single gas comput-er or table, and how to use switches to enriched air or oxygen to make the decompression more conservative.

Set the computer to your bottom gas, but use a richer blend on your deco gases. You follow

your computer and deco based on bottom gas. By using richer blends for you deco gas you

add in a level of conservatism. You can generate a table from desk top software to track

your actual oxygen exposure since the computer will be tracking a lesser exposure.

17. What is a gas-switch, extended no-stop dive?

A gas switch extended no-stop dive is a multilevel dive where the technical diver ascends to

a shallower depth and switches to a gas blend higher in oxygen to extend the no-stop time

without exceeding oxygen partial pressure limits.

18. What should you do if you find narcosis affecting your or your team mate’s ability to accomplish the mission and/or dive safely?

Ascend to a shallower depth and if necessary end the dive.

19. What is your END with enriched air and why?

The END with EANx is the same as air because oxygen is very likely just as narcotic

as nitrogen. Given all the oxygen is not metabolized by the body, you assume your

END does not change.


padi.com A-69


20. What is the “ideal” oxygen in a gas mix for a dive to 25 metres/83 feet?

40%


Team mates signal each other if they notice anything out of sorts. They

remind each other to check gas supplies, time, depth, etc.

22. Where is your team mates rank in your chain of back ups? What is the one back up your team mates provide that you cannot provide?

Your team mate is second, third or even further into your back up chain,

providing a back up only if your self reliant back ups fail. The exception is

that your team mate provides a back up brain, which is the only thing you

cannot provide yourself.

23. What are four guidelines to consider when planning to tec dive in an unfamiliar environment?

1. Gain experience with a new environment by doing recreational no-stop

dives first.

2. Master new area specific equipment and procedures in controlled

conditions before applying them on a more challenging tec dive.

3. Consult local tec divers for information on the site and for local

methodologies.

4. Remember to recognize the difference between local methods and

inappropriate and unsafe methods.

24. What is the myth about learning to dive with certain methodologies or in certain environments?

The myth is learning to dive in a specific environment or with a specific

methodology, qualifies you to dive everywhere.


Signature _________________________________________ Date ________________


A-70 padi.com



padi.com A-71



Study assignment: Tec Deep Diver Manual, pgs 176-179, Thinking Like a Tec Diver III, Tec Exercise 3.6

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 194-201, Gas Planning IV, Tec Exercise 4.2

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 202-209, Emergencies IV, Tec Exercise 4.3



1. Define “trust me dive” and explain you should not make them.

A “trust me” dive is a dive in which one diver relies on another to complete

the dive safely. Trust me dives should not be done because it violates one of

the primary safety rules for tec diving, which is the ability to complete the

dive independently at any point during the dive. It relegates your safety to

another diver.

2. List the six principals for surviving a tec dive.

1. The principle of secondary life support – you should have at least two

independent usable regulators, two independent sources of time, depth and

decompression information, and at least two methods of controlling buoyancy.

You should have at least two of anything that keeps you alive.

2. The principle of gas reserve – you should have ample gas to handle reasonably

possible emergencies and still complete your decompression (usually thirds).

3. The principle of self sufficiency – at any point in a dive, you should be able to

complete it independently.


A-72 padi.com


4. The principle of depth -- your dive plan should account for narcosis,

decompression, oxygen toxicity, and gas supply needs based on a planned

depth and time and/or a maximum contingency depth and time that you do

not exceed.

5. The principle of simplicity -- your dive should be planned as simple as

possible, with complexities eliminated.

6. The principle of procedure and discipline – you follow the rules and work

the procedures without exception on every dive, no matter how familiar

the dive and no matter how much experience you have.

3. What is run time? How do you use it?

Runtime is a continuous elapsed schedule you follow from the beginning of

the dive to the end of the dive when following a table. It includes bottom

time, stops, and ascents (though it does not include all ascents between deco

stops). Runtime can be used for gas-switch extended no-stop dives to add in

a measure of conservatism. By leaving slightly ahead of schedule, the dive

becomes more conservative.

4. Explain what you should do if you cannot switch to your shallower gas blend when making a gas switch extended no-stop dive.

Ascend immediately. You should still be within no-stop limits. If you have

passed the no-stop limit for your back gas, make a 3 minute stop or longer at

5 metres/15 feet.

5. Gas matching (optional): You are diving double 18 litre/104 cubic foot (working pressure 2400) cylinders filled to 150 bar/2200 psi. Your team mate will use double 21 litre/120 cubic foot (working pressure 2400) cylinders filled to 160 bar/2350 psi. If you gas match, what pressure should you have remaining at the end of the dive, and at what pressure should you turn the dive?

Metric

• Determine the actual volume in each set of doubles:

• 150 x (18 x 2) = 5400 160 x (21 x 2) = 6720

• Determine reserve for diver with larger cylinders: 6720 ÷ 3 = 2240. Divide

the reserve by the capacity of the smaller cylinders: 2240 ÷ 36 = 62. 2


padi.com A-73


• 62. 2 equals the reserve, in bar, the diver with smaller cylinders should

have at the end of the dive. Subtract this from the total bar to get the

pressure needed for the dive AND to return to the surface for the smaller

cylinders: 150 – 62. 2 = 87. 8

• Divide 87. 8 ÷ 2 = 43. 9 since you can only use half of this for the

bottom part of the dive. The other half is for returning to the surface/first

deco cylinder.

• Subtract: 150 – 43. 9 = 106. 1 = turn pressure.

Imperial

• Determine baseline for each set of doubles:

• (104 x 2) ÷ 2400 = . 087 (120 x 2) ÷ 2400 = . 1

• Determine actual volume in larger cylinders: 2350 x . 1 = 235 cf Divide

by thee to get reserve: 235 ÷ 3 = 78. 3 which equals reserve to

accommodate larger cylinders.

• Divide the reserve in the larger cylinders by the baseline of the smaller cylinder

to get the reserve in psi needed for the smaller cylinders to match the reserve of the

larger cylinders: 78. 3 ÷ .087 = 900.

• Subtract the reserve pressure from the actual pressure in the smaller

cylinders to the pressure needed for the dive and to return to the surface/

first deco cylinder: 2200 – 900 = 1300.

• Divide 1300 ÷ 2 = 650 since you can only use half of this for the bottom

part of the dive. The other half is for returning to the surface/first deco

cylinder.

• Subtract : 2200 – 650 = 1550 = turn pressure.

6. What should you do to ensure you don’t lose your decompression cylinders?

• Never stage them if you have any question whether or not you will be able to

retrieve them. Carry them with you.

• Insure the cylinders are tied off and/or secured wherever you stage them.

• Insure the valve is turned off especially if you stage them.

• Try to stage them away from other divers.

• Mark the cylinders well to inform other divers of their purpose and content.


A-74 padi.com


7. What do you do if your dive goes deeper and/or longer than planned?

If you are diving with a multigas computer, it may have the ability to calculate

adjusted stop depths and times. If you do not have the capability to adjust on the fly,

insure you have contingency/bail out tables to accommodate a change in depth and

time to your original profile.

8. What should you do if you miss a decompression stop?

It depends on the situation. If you can, immediately (within one minute) redescend

and complete the stop, plus one minute, according the normal schedule. If you

cannot redescend (gas supply restriction), stay at the next stop for the combined

time of both stops (gas permitting). Extend your 6 meter/20 foot stop and your final

stop by 1.5 times the normal schedule.

9. What should you do if you have a delay in your ascent to a decompression stop?

The simplest action is that if you are delayed ascending to your first decompression

stop, add the delay to your bottom time and decompress according to the new

schedule. Between stops, delays are not usually as critical unless they are excessive

(more than two minutes). Do not count the delay as part of your decompression

time when you resume decompression.

10. What should you do if you omit some or all of your decompression?

If you omit the decompression from 6 metres/20 feet or shallower and do not have

DCS symptoms, return to the stop (gas permitting) within one minute and complete

your decompression schedule. Extend your last stop several minutes or more. If you

omit decompression from 6 metres/20 feet or shallower and do not have DCS

symptoms, but it takes longer than one minute to return to your stop depth, extend

your 6 meter/20 foot stop and/or the final stop by 1.5 (or longer on the final stop)

times the normal decompression. If you omit decompression from deeper than 6

metres/20 feet, return to the first stop as quickly as possible (ideally less than 5

minutes) and decompress according to schedule up to and including the 12 metre/ 40

foot stop. Extend the 9 metre/30 foot stop and all shallower stops by 1.5 times the

normal schedule. If you skipped all your decompression, assume you will get bent

and have your team begin preparing for emergency evacuation. Stay on 100 percent

oxygen until EMS arrives or you reach emergency medical care.


padi.com A-75


11. What should you do if you run out of gas?

Your first option is to see if your team mates or support can help by sharing

gas or bringing some down. If you exhaust a deco gas, ascend to the first

stop where you can use your next gas. Combine missed stops with the stop at

that depth unless this will prematurely exhaust that gas, too. In that case,

follow the decompression schedule and extend the shallower stops as much

as possible. If you exhaust a deco gas that you are using with a single gas

computer or table to make your decompression more conservative, simply

complete decompression on back gas.

12. How do you handle a lift bag that spills as it ascends be cannot be pulled back down to be redeployed?

One option is to send up a team mate’s lift bag/DSMB clipped to the same

line via carabineer or large bolt snap. A second option is for your team mate

to deploy a lift bag separately from yours.

13. What is a drift kit? What items would you have in it, and when would you use it?

A drift kit is a pocket or watertight container that contains items to make the

diver more visible at the surface. At a minimum it contains a signal tube or

DSMB and a whistle. Additional items in higher risk environments are:

signal mirror, portable EPIRB, flares and dye markers. It is used when the

diver surfaces and is unable to see or communicate with boat and/or it is too

far or too difficult to swim.


Signature _________________________________________ Date ________________


A-76 padi.com



padi.com A-77


Tec45KnowledgeDevelopmentThreeManual Supported Content

Study assignment: Tec Deep Diver Manual, pgs 192-194, Equipment IV, Tec Exercise 4.1

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 210-211, Thinking Like a Tec Diver IV, Tec Exercise 4.4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 222-227, Oxygen Window and Accelerated Decompression, Deep Stops, Tec Exercise 5.1


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 228-229, Techniques IV, Tec Exercise 5.2


1. Explain the difference and give examples of acceptable and unacceptable homemade gear. What is the most common homemade item used by tec divers?

Homemade gear is equipment that is made or modified by the diver versus equipment

that is manufactured by a dive company. Acceptable examples of homemade gear are:

specialized compass slates, bungee clips for securing accessories or stage/deco

cylinder straps. Unacceptable examples are: regulators, BCDs, lights or other

equipment that are critical to safety.

2. List four attitudes that characterize leading tec divers.

1. Humility -- they realize that they don’t know everything, and that there may be more

than one right way to do something. Their ego doesn’t get in the way of learning,

doing or teaching.

2. Open mindedness -- they never reject something just because it’s new or different,

and they listen to other viewpoints. They don’t fear change and they’re not threatened

by differing opinions.


A-78 padi.com


3. Analytical -- they accurately and realistically weigh the merits of a technology or

procedures for themselves and never accept something just because it’s new or

because someone else thinks it’s better. They don’t let what they like, dislike or

want to believe influence their conclusions.

4. Competent -- while they’re open to change and alternative ways to do things,

their own methodologies are solid and they can demonstrate a rationale and real-

istic basis for each. They’re quietly confident about how they dive, and they don’t

choose their methodologies based on “looking cool” or what someone else might

think or say.

3. What is the oxygen window?

The oxygen window is an oxygen-derived gradient that allows nitrogen to dissolve

out of the tissues faster. The higher the oxygen, the greater the gradient and the

faster the nitrogen can dissolve out of the tissues.

4. List three techniques you can use to make accelerated deco dives more conservative.

1. Use the tables for the next greater depth and/or time than actually called for.

2. Generate tables based on blends with less oxygen than actual, and/or set your

dive computer for blends with less oxygen than actual (note that you will need to

determine actual max depths and oxygen exposure)

3. Make a safety stop within the last decompression stop.

5. What are two primary options for conducting deep stops?

1. The first is to use a decompression model that inherently stops you deeper than

other models.

2. The second is to use a conventional dissolved gas decompression model

and then add deep stops.

6. Define a “drift hang,” and list four disadvantages of using it.

A “drift hang” (also called “blue water decompression”) is a technique in which

divers decompress along a line from a float or boat while adrift in the current.


padi.com A-79


Disadvantages include:

• Requires close coordination of all teams in water if all team will drift

together. You often can’t stagger teams going in and coming out. (This

isn’t an absolute; in some areas there are ways to stagger teams for drift

hangs, but typically it’s not the case. )

• Waiting for one diver can hold up the drift for several teams --

procedures include actions for disoriented divers (usually requires

sending up a bag and drifting under it) and accounting for them by

surface support.

• Surface support is usually mandatory.

• You must account for where you’ll drift. In some environments with strong

current, it’s possible to be pushed into water too shallow for decompression.

In other areas, it may be possible to drift into sea lanes with hazardous ship

traffic. Plans must account for preventing this.

7. What is the most important resource in a tec diving emergency and what provides this resource?

Your most important resource is time. Your gas reserve provides this resource.

8. What is an air break and how is it performed?

An air break is a 5 minute switch to a lower oxygen gas for every 25 minutes of

decompression. The break is not counted as part of your decompression time when

using dive tables. With a multigas computer, you switch to the break gas for the

duration of the break.


Signature _________________________________________ Date ________________


A-80 padi.com



padi.com A-81



Study assignment: Tec Deep Diver Manual, pg 230, Equipment V, Tec Exercise 5.3


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 231-232, Thinking Like a Tec Diver V, Tec Exercise 5.4.


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 233-235, Mission Planning, Tec Exercise 5.5.



To qualify you to make limited decompression dives using air, enriched air and

oxygen to a depth of 50 metres/165 feet or less. Certification as a Tec 50 diver

qualifies you to use two decompression gases of EANx and 100 percent oxygen to

make your decompression more conservative or to accelerate your decompression.

2. What is the priority and how do you respond to an unresponsive diver at depth during a decompression dive?

The first priority is getting the victim to the surface. Remember, however, the

recommendation to wait until the diver stops convulsing before bringing him up. Try

to maintain the regulator in mouth while ascending. Take the diver up yourself if

possible, and if, based on your decompression situation, you judge the risk of DCS is

not excessive. Do not drop the victim’s weight until you get to the surface to avoid an

uncontrolled ascent. If available, signal support divers to help with the rescue.


A-82 padi.com


3. In what situation could long hose gas sharing be necessary in the decompression phase of a technical dive?

If there are stops before the first gas switch, it may be necessary to supply gas to

the affected diver on those stops. It may also be necessary for air breaks.

4. Professionals involved with rescue sometimes cite the philosophy “Better thee than me.” What does this mean and how does it apply to tec diving?

This means that it you cannot help another diver if you’re in trouble, too, so your

first priority is staying safe. In addition, if you get into trouble, too, remaining

emergency resources must now be split among two divers.

5. How do you plan for “specific” mistakes and emergencies?

During “Live” (logistics) from A Good Divers Main Objective is To Live, tec divers

try to plan for foreseeable problems. If, for example, the visibility is poor, tec divers

should make provisions to avoid separation during the dive.

6. What are three reasons may you want to “tec dive” in a pool or shallow water?

1. To refresh your skills - For example: long hose drills, send up lift bags/DSMBs,

drift decompression, etc. – whatever skills you may need in an emergency, but

have not actually practiced in quite a few dives.

2. To extend your skills - For example, if may have to don and remove deco

cylinders in reduced visibility and heavy surface chop while hanging onto a

current line, it may be worth practicing doing this with your face entirely

underwater and eyes closed while hanging onto a line.

3. To invent mission specific skills – Your dive plan may call for doing something

highly specific, such as recovering a lost object. If you don’t know the best way

to rig the object for recovery, you may want to invent the procedure using a

duplicate of it in shallow water.


padi.com A-83


7. What is the most common mistake in mission planning? Where does mission planning rank with the other aspects of a tec dive?

The most common mistake in mission planning, and the most common reason

missions fail is trying to accomplish more than is reasonable in a single dive. The

mission ranks second to completing the dive safely.

8. For a presentation that you are going to give to local biologists on invertebrate pop-ulations on a local reef that about 2 kilometers/1 mile long, you are interested in estimating the number of sea stars per square metre/yard at depths between 30 meters/100 feet and 42 meters/140 feet. Your team plans to get this number; what subtasks might this mission entail? Would it be reasonable to do this in a single dive? How many dives might it take assuming a single team of three divers?

[Answers may vary, but should show planning, forethought, attention to detail and

awareness of effects on the dive.]

Subtasks may include:

• Setting up mooring lines at the ends of the reef and along the reef.

• Setting up a grid of 10 square meters/yards.

• Photographing the grid.

• Determining the total number of square meters of reef based on length and width.

• Breaking the reef into several sections in order to count.

• Counting the stars in each section.

Each subtask may require one or two dives, to complete the subtask.


Signature _________________________________________ Date ________________


A-84 padi.com



padi.com A-85



Study assignment: Tec Deep Diver Manual, pgs245-253, Chapter Six, all Tec Exercises.


Tec50KnowledgeReviewTwoPlease complete this review to hand in to your instructor. If there’s something you don’t under-stand, review the related material. If you still don’t understand, be sure to have your instructor explain it to you.

1. Define decompression sickness, arterial gas embolism and decompression illness:

Arterial gas embolism (AGE) is the condition in which air bubbles enter the bloodstream

through a lung rupture, usually the result of holding the breath during ascent.

Decompression sickness (DCS) is the condition in which inert gas (nitrogen) forms

bubbles in the tissues and bloodstream as it comes out of solution due to high

supersaturation following ascent.

Decompression illness is the field term for both DCS and AGE together.

2. List the signs and symptoms of decompression illness.

Signs and symptoms of DCI include pain in the joints or mid limb, undue fatigue,

inability to urinate, blurred vision, blotchy skin rash, tingling in the extremities, swelling,

vertigo, hearing or speech impairment, paralysis, numbness, unconsciousness, bloody

froth from the mouth, loss of coordination, personality change and respiratory/cardiac

arrest. The symptoms may be immediate or delayed.

3. Explain the procedure for first aid for suspected decompression illness.

• Keep the patient lying down; on the back is fine for a responsive patient, left side

down (recovery position) for an unresponsive breathing patient.

• Monitor airway, breathing and circulation (ABCs) and administer CPR

as necessary.


A-86 padi.com


• Administer emergency oxygen to a breathing patient, ideally 100 percent via a

demand system (for breathing patient).

• For non-breathing patients, use freeflow oxygen while providing rescue breaths

through a pocket mask or a manually triggered resuscitator valve if available

and you’re trained in its use . If the patient resumes breathing, switch to the

demand or nonrebreather mask.

• Continue oxygen until you get the patient into emergency medical care, or until

you run out. Monitor the oxygen pressure gauge; don’t let the cylinder run

empty with the mask still on the patient. You can also use high O2 percent EANx

if the oxygen runs out.

• Responsive patients should hydrate themselves with water or isotonic fluids.

• Contact emergency medical care and the diver emergency service (DAN, DES)

that serves the area and get the patient into medical care and ultimately to a

recompression facility as guided by the diver emergency service and the local

medical system.

4. Explain how to administer a field neurological exam.

• Have the patient follow your finger with both eyes. They should track together.

• Have the patient use both hands to squeeze yours. Weakness on one side

suggests a problem.

• Ask the patient to close both eyes, stretch out the arms and then bend at the

elbows to touch the nose with fingertips. The inability to do this with both or

either hand suggests a problem.

• The patient should be able to stand on one foot.

• Snap your fingers on either side of the patients head. Ask if there is any significant

difference in loudness. A significant difference can suggest nerve damage, though

with this test ear squeeze or water in the ear canal could be at fault.

5. Explain how having diver accident insurance can make treatment for decompres-sion illness more effective.

Because the more quickly a patient begins treatment the more likely a favorable

outcome, you want to minimize anything that would delay treatment should you

ever need it. Diver accident insurance minimizes delays by establishing the

financial coverage.


padi.com A-87


6. How does administering oxygen benefit a patient with decompression illness?

Breathing pure oxygen helps oxygenate tissues suffering from restricted blood flow due to

bubble formation. This helps protect these tissues until the patient receives recompression.

Pure oxygen increases the pressure differential of the excess dissolved inert gas, speeding

it out of the body faster. This minimizes and slows further bubble growth, reducing further

and worsening symptoms.

7. List the steps you will take as a prudent tec diver to broaden your abilities and limits within tec diving.

• Gain experience

• Push your comfort zone gently

• Learn from those with experience

• Respect the limits

• Continue training

8. What quality should you have to extend your personal limits at an appropriate pace?

Patience – don’t move on until you are prepared and qualified.

9. What is trimix?

Trimix is a blend of oxygen, helium and nitrogen.

10. What are the advantages and disadvantages of diving with trimix?

Advantages

Reduced narcosis

Reduced gas density

Reduced oxygen exposure

Disadvantages

Decompression times and schedules

Theoretical higher DCS risk

Cost

Heat loss


A-88 padi.com


11. What will your qualifications be with respect to diving with trimix as a Tec 50 diver?

If your instructor is a DSAT Tec Trimix instructor, you may have the option of using

trimix on Tec 50 Training Dive Four, but this does not certify you or qualify you to

dive trimix independently. To dive trimix, continue your training with the Tec Trimix

65 course and/or the Tec Trimix Diver course.

12. (Metric) You plan a dive to 44 metres using a single gas enriched air computer set for EANx26. You plan to decompress using EANx80 from 9 metres to the surface. You estimate that your bottom time will be 40 minutes. Your dive tables for EANx26 show that 40 minutes at 44 metres requires 3 minutes decompression at 12 metres, 10 at 9 metres, 17 at 6 metres and 43 at 3 metres. Your ascent rate is 10 mpm. Your SAC rate is 19 litres per minute on the working part of the dive, and 16 lpm (litres per minute) when decompressing.

• Following the rule of thirds, how much of each gas do you need for this dive?

Answer: 6771 litres of EANx26; 2489 litres of EANx80

• If you have twin 18 litre cylinders with 170 bar of EANx26 do you have enough EANx26 for the dive? If you have a 13 litre cylinder with 205 bar of EANx80, do you have enough EANx80 for the dive? How much do you have of each?

Answer: No and yes.

What are your OTUs and “CNS clock” after the dive?

Answer: OTUs=161.5; CNS%=85.1%

• If you’ll be diving again in two and a half hours, and you’ll be staying within the mission averages for three days of diving, how much “CNS clock” time and how many OTUs can you have on the second dive?

Answer: Allowable CNS = 64%; allowable OTUs = 458.5


padi.com A-89


Depth Time SAC C.Fac Vol Gas PO2 OTU/min OTUs/min CNS% CNS%

44 m 40 19 5.5 4180 EANx26 1.43* 1.67 66.8 0.83 33.2

28 m(a) 3 19 4.0 228 EANx26 1.04 1.07 3.2 0.42 1.3%

12 m 3 16 2.2 106 EANx26 0.57 0.20 0.6 0.14 0.4%

9 m 10 16 1.9 304 EANx80 1.52 1.81 18.1 2.22 22.2%

6 m 17+1 16 1.6 461 EANx80 1.28 1.4 26.11 0.55 9.9%

3 m 43 16 1.3 894 EANx80 1.04 1.07 46.0 0.42 18.1%

[*Note: Actual PO2 = 1.4; 1.43 from rounding on table to 45 m.]

EANx26 = 4180+228+106=4514 l; 4514 X 1.5 = 6771 litres

EANx80=304+461+894=1659 l; 1659 X 1.5 = 2489 liters

18 litres x 170 = 3060 litres, 3060 x 2 (doubles) = 6120 litres EANx

13 litres x 205 = 2665 litres EANx80

OTUs = 66.8+3.2+0.6+18.1+26.11+46.0=160.8

“CNS clock” = 33.2%+1.3%+0.4%+22.2%+9.9%+18.1%=85.1%

After two and a half hours, CNS 85.1% = 36%; 100%-36%=64%

Three day mission allows 1860 OTUs, average 620 per day. 620-160.8 = 459.2

12. (Imperial) You plan a dive to 145 feet using a single gas enriched air computer set for EANx26. You plan to decompress using EANx80 from 30 feet to the surface. You esti-mate that your bottom time will be 40 minutes. Your dive tables for EANx26 show that 40 minutes at 145 feet requires 3 minutes decompression at 40 feet, 10 at 30 feet, 17 at 20 feet and 43 at 10 feet. Your ascent rate is 30 fpm. Your SAC rate is .8 cubic feet per min-ute on the working part of the dive, and .65 cf when decompressing.


Answer: 285 cubic feet of EANx26; 101 cf of EANx80

• If you have twin 104 cf cylinders, working pressure 2400 psi, with 2500 psi of EANx26 do you have enough EANx26 for the dive? If you have a 104 cf cylinder, working pressure 2400, with 2300 psi of EANx80, do you have enough EANx80 for the dive? How much do you have of each?

Answer: No and no. EANx26 = 216 cf; EANx80 = 100 cf (99.8)


A-90 padi.com


• What are your OTUs and “CNS clock” after the dive?

Answer: OTUs=160.4; CNS%=85.1%


Answer: Allowable CNS = 64%; allowable OTUs = 458.3

Depth Time SAC C.Fac Vol Gas PO2 OTU/min OTUs/min CNS% CNS%

145 40 .8 5.5 176.0 EANx26 1.44* 1.69 67.6 0.83 33.2%

93 3 .8 4.0 9.6 EANx26 1.05 1.08 3.2 0.42 1.3%

40 3 .65 2.2 4.3 EANx26 0.58 0.21 0.6 0.14 0.4%

30 10 .65 1.9 12.4 EANx80 1.53 1.82 18.2 2.22 22.2%

20 17+1 .65 1.6 18.7 EANx80 1.28 1.45 26.1 0.55 9.9%

10 43 .65 1.3 36.3 EANx80 1.04 1.07 46.0 0.42 18.1%

EANx26=176+9.6+4.3=189.9 cf; 189.9 X 1.5=285 cf

EANx80=12.4+18.7+36.3=67.4 cf; 67.4 X 1.5 =101 cf

2500/2400 = 1.04, 1.04 x 104 = 108 cf, 108 x 2 (doubles) = 216 cf

2300/2400 = .96, .96 x 104 = 100 cf (99.8)

OTUs=67.6+3.2+0.6+18.2+26.1+46.0=161.7

“CNS clock” = 33.2%+1.3%+0.4%+22.2%+9.9%+18.1%=85.1%

After two and a half hours, CNS 85.1% = 36%; 100%-36%=64%

Three day mission allows 1860 OTUs, average 620 per day. 620-161.7 = 458.3

13. (Metric) You plan a dive to 50 metres using a single gas enriched air computer set for air. You plan to decompress using oxygen from 6 metres to the surface. Using desk top software you estimate that your bottom time will be 25 minutes. Using desk top deco software, you generate air dive tables that show that 25 minutes at 50 metres requires 2 minutes decompression at 9 metres, 4 at 6 metres and 13 at 3 metres. Your ascent rate is 10mpm. Your SAC rate is 22 litres/min on the working part of the dive, and 18 l /min when decompressing.


padi.com A-91



Air needed for the dive (with 1/3 reserve): (3300 + 352 + 68.4) x 1.5 = 5580.6

O2 needed for the dive (with 1/3 reserve): (115.2 + 327.6) x 1.5 = 664.2

If you have twin 21 litre cylinders with 150 bar of air, how much gas volume do you have?

Total volume in doubles: 21 x 2 (twins) = 42 x 150 = 6300

Is it enough for the dive?

Yes, 6300 > 5580.6

At what back gas pressure should you leave the bottom to assure you can complete your decompression and have a one-third reserve left?

Air needed for the dive (with 1/3 reserve): 5580.6

Bottom volume needed / total volume = conversion: 3300 / 6300 = .52

Conversion x act press = pressure allowed at depth (PAD): .52 x 150 = 78

Total pressure - PAD = turn pressure: 150 -78 = 72

If you have a 7 litre cylinder with 195 bar of oxygen, how much gas volume do you have?

Oxygen cylinder total volume = 7 x 195 = 1365

O2 volume needed (with one third reserve) is 664.2


Yes, 1365 > 664.2


OTUs = 67.57 “CNS clock” = 31.45


A-92 padi.com


• If you will be diving again in three hours, and you will be staying within the mission aver-ages for five day of diving, how much “CNS clock” time and how many OTUs can you have on the second dive?

40% (31.45) drops to 16% after 3 hours. 100 - 16 = 84%

On the second dive you are allowed 460 - 67.57 = 392.43 (for 5 day average)

Depth Time SAC C.Fac Vol Gas PO2 OTUs/min OTUs CNS%/min CNS

50 25 22 6.0 3300 Air 1.28 1.45 36.26 .55% 13.75

30(a) 42 22 4.0 352 Air .84 .73 2.92 .28%.0% 1.12

9 18 1.9 68.4 Air .4 .0

6 4 18 1.6 115.2 02 1.6 1.92 7.68 2.22 % 8.88

3 14* 18 1.3 327.6 02 1.3 1.48 20.72 .55% 7.7

67.57 31.45

(a) Midpoint = (bottom - first stop) ÷ 2 + first stop (50 - 9) ÷ 2 + 9 = 29.5 * Add one minute

(13 + 1) for every third stop.

Air total = 3300 + 352 + 68.4 = 3720.4 x 1.5 = 5580.6

Oxygen total = 115.2 + 327.6 = 442.8 x 1.5 = 664.2

13. (Imperial) You plan a dive to 165 feet using a single gas enriched air computer set for air. You plan to decompress using oxygen from 20 feet to the surface. You estimate that your bottom time will be 25 minutes. Using desk top deco software, you generate air dive tables that show that 25 minutes at 165 feet requires 2 minutes decompression at 30 feet, 4 at 20 and 13 at 10 feet. Your ascent rate is 30 fpm. Your SAC rate is .78 cf/min on the working part of the dive and .64 during decompression.

• Following the rule of thirds, how much of each gas do you need for the dive?

Air: (117 + 15.6 + 2.4) x 1.5 = 202.5

O2: (4.1 + 11.65) x 1.5 = 23.625


padi.com A-93


• If you have twin 120 cubic foot cylinders with a working pressure of 2400 with 2200 psi of air, how much gas volume do you have?

Total volume of air available in doubles: 120 x 2 = 240

Cylinder Baseline = capacity ÷ working pressure: 240 ÷ 2400 = .1

Volume in doubles at 2200 psi: .1 x 2200 = 220

Volume of air needed: 202


Yes, 220 > 202

At what back gas pressure should you leave at the bottom to assure you can complete your decompression and have one third reserve left?

Turn pressure = starting pressure - (bottom volume/baseline)

2200 - (117/.1) = 1030

If you have a 50 cf cylinder, working pressure 3000, with 2870psi of oxygen, how

much gas volume do you have?

Internal volume = capacity/working pressure: 50 ÷ 3000 = .0167

Volume of O2 in cylinder at 2870 psi: .0167 x 2870 = 47.93

Volume of O2 needed: 23.63


Yes, 47.8 > 23.7


OTUs = 68.64 CNS = 31.73


A-94 padi.com


• If you will be diving in three hours, and you will be staying within mission averages for five days of diving, how much “CNS clock” time and how many OTUs can you have on the sec-ond dive?

31.73 drops to 16% after a 3 hour surface interval

On second dive you are allowed 460 - 68.64 = 391.36 (5 day average)

Depth Time SAC C.Fac Vol Gas PO2 OTUs/min OTUs CNS%/min CNS

165 25 .78 6.0 117 Air 1.29 1.46 36.5 .55% 13.75%

98(a) 52 .78 4.0 15.6 Air .85 .74 3.7 1.4%

30 .64 1.9 2.4 Air .40

20 4 .64 1.6 4.1 02 1.61 1.93 7.72 2.22 % 8.88 %

10 14* .64 1.3 11.65 02 1.3 1.48 20.72 .55% 7.7%

68.64 31.73%

(a) midpoint = (bottom - first stop) ÷ 2 + first stop (165 - 30) ÷ 2 + 30 = 97.5 * Add one minute

for every third stop.

Air Total = 133.4 x 1.5 = 200cf

Oxygen Total = (4.1 + 10.8) x 1.5 = 22.35


Signature _________________________________________ Date ________________


padi.com A-95


IndependentStudyAssignments You may copy the following independent study assignments to hand out to students. See the instructor guides for required presentations. In the Tec 40 course, see the notes relating to Other Delivery Content, Tec 40, and Tec 45, Knowledge Development One, II. Equipment about the appropriate study assignments for the equipment your students will use in the course.


Study assignment: Tec Deep Diver Manual, pgs xi, pg xiii Your Obligations and Responsibilities, pg xiv Diver Accident Insurance, pg 1-9 including Tec Exercise 1.1. Disregard Tec Deep and Apprentice Tec Diver Certification Limits discussions. You may skip question 6 in the exercise.



Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 84-87, Oxygen Compatibility Review, Manufacturer Warranties and Hyperoxic Gases

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 35-50, Gas Planning I, Tec Exercise 1.3


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 51-54, Team Diving I, Tec Exercise 1.4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 54-59, Techniques and Procedures I, Tec Exercise 1.5, pgs 107-109, Team Diving Gas Handling Considerations, Tec Exercise 2.4 questions 4-8, pgs 115-122, Techniques and Procedures III, Tec Exercise 2.5

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 60-64, Emergency Procedures I, Tec Exercise 1.6, pgs 123-129, Emergency Procedures II, Tec Exercise 2.6


A-96 padi.com



1. Define “recreational diving”, “technical diving”, and explain what is not technical diving.

2. List six general risks and hazards that technical diving presents that either don’t exist or aren’t as severe in recreational diving.

3. What single statement sums up the difference between recreational and technical diving?

4. What are the goals of the Tec 40 course?


padi.com A-97


5. What are the limits of the Tec 40 certification?

6. What are the six characteristics of a responsible technical diver:

7. What should you do if you can’t or won’t accept the risks and responsibilities demanded by technical diving?


A-98 padi.com


8. Describe the proper types, number, location and configuration within your rig of the following equipment components as to how your gear will look when worn.

Valves & Cylinders:

Right Regulator accessories:

Left Regulator accessories:

BCD and harness:

Instruments:


padi.com A-99


Cutting tools:

Pockets:

Clips:

9. List the three types of dive computer you can use for technical deep diving with air and enriched air, along with the advantages and disadvantages of each.

Standard Air Computer:

Enriched Air Computers:


A-100 padi.com


Multigas Computers:

10. What are the recommended maximum oxygen partial pressures for technical deep diving?

11. Using the maximum depth formulas, what are the maximum depths and decom-pression depths for EANx48?

(Metric) if your SAC rate is 24 litres/min, how much gas volume do you need for 20 minutes at 30 metres? What would your total volume be with a reserve based on the rule of thirds?

(Imperial) if you SAC rate is .8 cubic feet/min, how much gas volume do you need for 20 minutes at 90 feet? What would your total volume be with a reserve based on the rule of thirds?


padi.com A-101


12. What are the signs and symptoms of CNS oxygen toxicity, and what’s the primary way you avoid it?

13. What are the signs and symptoms of pulmonary oxygen toxicity, and what is the primary way to avoid it?


15. What is the rule regarding aborting a technical dive?



A-102 padi.com


17. What is the primary hazard of excessive positive buoyancy, and how do you man-age this hazard?

18. Describe how to find the minimum weight and the minimum buoyancy you need for a technical deep dive.

19. How does a technical dive in a dry suit differ from a recreational dive in a dry suit? What’s the recommended number of recreational dives in a dry suit that you should have before technical diving in one?


padi.com A-103


20. Describe the procedure for sharing gas with your long hose.

21. What are the emergency procedures for a massive regulator (second stage) free flow at depth?

22. What are the emergency procedures for a damaged doubles manifold at depth?

23. What is the over-riding mission of all technical dives?

24. How and why does “cutting corners” lead to accidents in technical diving?


A-104 padi.com



padi.com A-105



Study assignment: Tec Deep Diver Manual, pgs 64-64, Thinking Like a Technical Diver I, Tec Exercise 1.7

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 88-93 Introduction to Decompression Stop and Gas Switch, Extended No Stop Diving, Equivalent Air Depths (Continued) and Equivalent Narcotic Depths, Ideal Enriched Air for a Particular Depth, Determining Gas Supply and Reserve Requirements for Multiple Depths and Decompression stops (first page only); pgs 97-99 Desk Top Decompression Software Tec Exercise 2.2, Questions 1-8 & 10. Pg 157 down to “Example” on pg 158, Planning a Decompression Dive Using a Single Gas Computer.



Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 101-107, Thinking Like a Technical Diver II, Team Diving II, Tec Exercise 2.3, pgs 109-113, Predive Check, Technical Diving Hand Signals, Tec Exercise 2.4, questions 1-3 and 9-15.

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 167, When to Make Cylinder Switches, pgs 162-166, Emergencies III, Tec Exercise 3.3


1. Describe a suitable, rigged stage deco bottle “package.”


A-106 padi.com


2. Briefly list the guidelines regarding material and equipment compatibility using enriched air and oxygen. What do you risk if you fail to follow these guidelines?

3. Explain how you determine your required decompression stops using a single gas computer or table, and how to use switches to enriched air or oxygen to make the decompression more conservative.


padi.com A-107


4. What do you assume your END is with enriched air? Why?

5. What are the advantages and risks of using desk top decompression software?

6. What should you assume about every technical dive, and what should you take for granted?

7. What is your most important resource in a tec diving emergency, and what provides this resource?

8. What is the principle of your gas reserve?


A-108 padi.com


9. What is the recall phrase for the seven segments of planning a tec dive, and what does the phrase stand for?

10. Why do all team members on a technical dive usually use the same gases?

11. What four markings should be on every cylinder used on a technical dive? Which should be easy to read by all team members while worn? Why are these markings required?


padi.com A-109


12. Who must check the pressure and oxygen analysis of every cylinder used for a technical dive?

13. What is the predive check recall phrase in tec diving? What does it stand for, and what steps does the predive check include? Being Wary Reduces All Failures.

14. What is your turn pressure if you have 190 bar or 2800 psi in your cylinders and your are using a reserve of one-third?

15. Describe how to perform a bubble check and a descent check.

16. The thumbs up means______ ___ ____ _____ ____ ___ .


A-110 padi.com


17. What is the ideal position and stop depth level when decompressing? What is the most important skill you need for decompressing?


Signature _________________________________________ Date ________________


padi.com A-111


Tec40KnowledgeDevelopmentThreeOther Delivery Content, Tec 40-6

Study assignment: Tec 40 Handout 6


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 204, sidebar, How Do I Figure 1.5 Times with a Computer?


1. What is one of the most common preventable causes of death in technical diving?

2. What is the recall acronym for gas switches? Describe the gas switch procedure and how the acronym prompts you.

3. List five guidelines that reduce the chance of accidentally switching to an unsafe gas blend at depth.


A-112 padi.com


4. Describe what to do if you experience possible symptoms of CNS oxygen toxicity.

5. What is the “ideal” gas blend for a dive to 25 metres/83 feet?

6. What is the general procedure if you can’t return to your planned ascent line?

7. How do you learn to account for environmental variables, such as current, visibility, temperature and waves when planning a tec dive?

8. What are four guidelines to consider when planning a tec dive in an unfamiliar environment?


padi.com A-113


9. What assumption do technical divers make when they plan a dive?

10. List six principles for surviving a tec dive.




Signature _________________________________________ Date ________________


A-114 padi.com



padi.com A-115



Study assignment: Tec Deep Diver Manual, pgs 10-33, Equipment I, Tec Exercise 1.2, pgs 80-87, Equipment II, Tec Exercise 2.1, pgs 142-145, Equipment III, Tec Exercise 3.1 Watch the TecRec Equipment Setup and Key Skills video.


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 93-97, Determining Gas Supply and Reserve Requirements for Multiple Depths and Decompression Stops pgs 146 -161, Gas Planning III, Tec Exercise 3.2

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 167-172, Turn Around Points and Environmental Variables, Tec Exercise 3.4, questions 2-4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 173-175, Team Diving III, Tec Exercise 3.5




A-116 padi.com


2. What are your responsibilities during the Tec 45 course?

3. What is meant by “standardized technical rig” and why do you need to apply it?

4. Describe the proper types, number, location and configuration within your rig of the following equipment components and how your gear will look when worn:

Manifold (if applicable) -


padi.com A-117


Right regulator and accessories –

Sidemount –

Left regulator and accessories –

BCD and harness -

Instruments –


A-118 padi.com


Compass –

Timing Device & Depth Gauge –

Cutting tools –

Pockets and clips -

5. Describe a suitably rigged stage/deco bottle.


padi.com A-119


6. List three reasons why tec divers consider a slate standard equipment.

7. List three types of dive computers you can use for technical diving with air and enriched air, along with the advantages and disadvantages of each.

8. Name two buoyancy control devices and explain what is meant by “appropriate back up buoyancy. ”


A-120 padi.com


9. How does a technical dive in dry suit differ from a recreational dive? What is the recommended number of recreational dives in a dry suit that you should have before using it on a technical dive?

10. What are four different weighting options for tec diving and list the advantages and disadvantages of each.


padi.com A-121



12. List the guidelines regarding material and equipment compatibility using enriched air and oxygen. What do you risk if you fail to follow these guidelines?

13. List four reasons why DSMBs are replacing lift bags in tec diving situations.


A-122 padi.com


14. (Metric) If your SAC rate is 24 litres/minute, how much gas volume do you need for 20 minutes at 30 metres? What would your total volume be with a reserve based on the rule of thirds?

14. (Imperial) If you SAC rate is . 8 cfm, how much gas volume do you need for 20 minutes at 90 feet?

15. (Metric) What is your turn pressure for your back gas based on the dive profile information below? Do you have enough back gas to do the dive and return with a one-third reserve?

15. (Imperial) What is your turn pressure for your back gas based on the dive profile information below? Do you have enough back gas to do the dive and return with a one-third reserve?


padi.com A-123


16. Explain how you determine your required decompression stops using a single gas computer or table, and how to use switches to enriched air or oxygen to make the decompression more conservative.

17. What is a gas-switch, extended no-stop dive?

18. What should you do if you find narcosis affecting your or your team mate’s ability to accomplish the mission and/or dive safely?

19. What is your END with enriched air and why?

20. What is the “ideal” oxygen in a gas mix for a dive to 25 metres/83 feet?


A-124 padi.com



22. Where is your team mates rank in your chain of back ups? What is the one back up your team mates provide that you cannot provide?

23. What are four guidelines to consider when planning to tec dive in an unfamiliar environment?

24. What is the myth about learning to dive with certain methodologies or in certain environments?


Signature _________________________________________ Date ________________


padi.com A-125



Study assignment: Tec Deep Diver Manual, pgs 176-179, Thinking Like a Tec Diver III, Tec Exercise 3.6

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 194-201, Gas Planning IV, Tec Exercise 4.2

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 202-209, Emergencies IV, Tec Exercise 4.3



1. Define a “trust me dive” and explain why you should not make them.

2. List the six principals for surviving a tec dive.


A-126 padi.com


3. What is run time? How do you use it?

4. Explain what you should do if you cannot switch to your shallower gas blend when making a gas switch extended no-stop dive.

5. Gas matching (optional): You are diving double 18 litre/104 cubic foot (working pressure 2400) cylinders filled to 150 bar/2200 psi. Your team mate will use double 21 litre/120 cubic foot (working pressure 2400) cylinders filled to 160 bar/2350 psi. If you gas match, what pressure should you have remaining at the end of the dive, and at what pressure should you turn the dive?


padi.com A-127


6. What should you do to ensure you don’t lose your decompression cylinders?


A-128 padi.com


7. What do you do if your dive goes deeper and/or longer than planned?

8. What should you do if you miss a decompression stop?

9. What should you do if you have a delay in your ascent to a decompression stop?

10. What should you do if you omit some or all of your decompression?


padi.com A-129


11. What should you do if you run out of gas?

12. How do you handle a lift bag that spills as it ascends be cannot be pulled back down to be redeployed?

13. What is a drift kit? What items would you have in it, and when would you use it?


Signature _________________________________________ Date ________________


A-130 padi.com



padi.com A-131


Tec45KnowledgeDevelopmentThreeManual Supported Content

Study assignment: Tec Deep Diver Manual, pgs 192-194, Equipment IV, Tec Exercise 4.1

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 210-211, Thinking Like a Tec Diver IV, Tec Exercise 4.4

Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 222-227, Oxygen Window and Accelerated Decompression, Deep Stops, Tec Exercise 5.1


Manual Supported Content Study assignment: Tec Deep Diver Manual, pgs 228-229, Techniques IV, Tec Exercise 5.2


1. Explain the difference and give examples of acceptable and unacceptable home-made gear. What is the most common homemade item used by tec divers?

2. List four attitudes that characterize leading tec divers.


A-132 padi.com


3. What is the oxygen window?

4. List three techniques you can use to make accelerated deco dives more conservative.

5. What are two primary options for conducting deep stops?

6. Define a “drift hang,” and list four disadvantages of using it.


padi.com A-133


7. What is the most important resource in a tec diving emergency and what provides this resource?

8. What is an air break and how is it performed?


Signature _________________________________________ Date ________________


A-134 padi.com



padi.com A-135



Study assignment: Tec Deep Diver Manual, pg 230, Equipment V, Tec Exercise 5.3


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 231-232, Thinking Like a Tec Diver V, Tec Exercise 5.4.


Manual Supported Content Study assignment: Tec Deep Diver Manual, pg 233-235, Mission Planning, Tec Exercise 5.5.



2. What is the priority and how do you respond to an unresponsive diver at depth during a decompression dive?


A-136 padi.com


3. In what situation could long hose gas sharing be necessary in the decompression phase of a technical dive?

4. Professionals involved with rescue sometimes cite the philosophy “Better thee than me.” What does this mean and how does it apply to tec diving?

5. How do you plan for “specific” mistakes and emergencies?

6. What are three reasons may you want to “tec dive” in a pool or shallow water?


padi.com A-137


7. What is the most common mistake in mission planning? Where does mission planning rank with the other aspects of a tec dive?

8. For a presentation that you are going to give to local biologists on invertebrate pop-ulations on a local reef that about 2 kilometers/1 mile long, you are interested in estimating the number of sea stars per square metre/yard at depths between 30 meters/100 feet and 42 meters/140 feet. Your team plans to get this number; what subtasks might this mission entail? Would it be reasonable to do this in a single dive? How many dives might it take assuming a single team of three divers?


Signature _________________________________________ Date ________________


A-138 padi.com



padi.com A-139



Study assignment: Tec Deep Diver Manual, pgs245-252, Chapter Six, all Tec Exercises.


Tec50KnowledgeReviewTwoPlease complete this review to hand in to your instructor. If there’s something you don’t understand, review the related material. If you still don’t understand, be sure to have your instructor explain it to you.

1. Define decompression sickness, arterial gas embolism and decompression illness:

2. List the signs and symptoms of decompression illness.

3. Explain the procedure for first aid for suspected decompression illness.


A-140 padi.com


4. Explain how to administer a field neurological exam.

5. Explain how having diver accident insurance can make treatment for decompres-sion illness more effective.


padi.com A-141


6. How does administering oxygen benefit a patient with decompression illness?

7. List the steps you will take as a prudent tec diver to broaden your abilities and lim-its within tec diving.

8. What quality should you have to extend your personal limits at an appropriate pace?

9. What is trimix?



A-142 padi.com



12. (Metric) You plan a dive to 44 metres using a single gas enriched air computer set for EANx26. You plan to decompress using EANx80 from 9 metres to the surface. You estimate that your bottom time will be 40 minutes. Your dive tables for EANx26 show that 40 minutes at 44 metres requires 3 minutes decompression at 12 metres, 10 at 9 metres, 17 at 6 metres and 43 at 3 metres. Your ascent rate is 10 mpm. Your SAC rate is 19 litres per minute on the working part of the dive, and 16 lpm (litres per minute) when decompressing.


• If you have twin 18 litre cylinders with 170 bar of EANx26 do you have enough EANx26 for the dive? If you have a 13 litre cylinder with 205 bar of EANx80, do you have enough EANx80 for the dive? How much do you have of each?

What are your OTUs and “CNS clock” after the dive?



padi.com A-143


12. (Imperial) You plan a dive to 145 feet using a single gas enriched air computer set for EANx26. You plan to decompress using EANx80 from 30 feet to the surface. You estimate that your bottom time will be 40 minutes. Your dive tables for EANx26 show that 40 minutes at 145 feet requires 3 minutes decompression at 40 feet, 10 at 30 feet, 17 at 20 feet and 43 at 10 feet. Your ascent rate is 30 fpm. Your SAC rate is .8 cubic feet per minute on the working part of the dive, and .65 cf when decompressing.


• If you have twin 104 cf cylinders, working pressure 2400 psi, with 2500 psi of EANx26 do you have enough EANx26 for the dive? If you have a 104 cf cylinder, working pressure 2400, with 2300 psi of EANx80, do you have enough EANx80 for the dive? How much do you have of each?


A-144 padi.com



• If you’ll be diving again in two and a half hours, and you’ll be staying within the mis-sion averages for three days of diving, how much “CNS clock” time and how many OTUs can you have on the second dive?

13. (Metric) You plan a dive to 50 metres using a single gas enriched air computer set for air. You plan to decompress using oxygen from 6 metres to the surface. Using desk top software you estimate that your bottom time will be 25 minutes. Using desk top deco software, you generate air dive tables that show that 25 minutes at 50 metres requires 2 minutes decompression at 9 metres, 4 at 6 metres and 13 at 3 metres. Your ascent rate is 10mpm. Your SAC rate is 22 litres/min on the working part of the dive, and 18 l /min when decompressing.


padi.com A-145



If you have twin 21 litre cylinders with 150 bar of air, how much gas volume do you have?


At what back gas pressure should you leave the bottom to assure you can complete your decompression and have a one-third reserve left?

If you have a 7 litre cylinder with 195 bar of oxygen, how much gas volume do you have?




A-146 padi.com


• If you will be diving again in three hours, and you will be staying within the mission aver-ages for five day of diving, how much “CNS clock” time and how many OTUs can you have on the second dive?

13. (Imperial) You plan a dive to 165 feet using a single gas enriched air computer set for air. You plan to decompress using oxygen from 20 feet to the surface. You estimate that your bottom time will be 25 minutes. Using desk top deco software, you generate air dive tables that show that 25 minutes at 165 feet requires 2 minutes decompression at 30 feet, 4 at 20 and 13 at 10 feet. Your ascent rate is 30 fpm. Your SAC rate is .78 cf/min on the working part of the dive and .64 during decompression.

• Following the rule of thirds, how much of each gas do you need for the dive?


padi.com A-147


• If you have twin 120 cubic foot cylinders with a working pressure of 2400 with 2200 psi of air, how much gas volume do you have?


At what back gas pressure should you leave at the bottom to assure you can complete your decompression and have one third reserve left?

If you have a 50 cf cylinder, working pressure 3000, with 2870psi of oxygen, how

much gas volume do you have?




A-148 padi.com


• If you will be diving in three hours, and you will be staying within mission averages for five days of diving, how much “CNS clock” time and how many OTUs can you have on the second dive?


Signature _________________________________________ Date ________________


padi.com A-149


OtherDeliveryContentHandOutsCopy the following independent study handouts to give to students.

Tec40OtherDeliveryContent,Tec40-1

Studyassignment:Tec40Handout1

Learning Objectives

By the end of this section, you should be able to answer these questions:

1. How do the Tec 40, Tec 45 and Tec 50 courses fit together as the overall DSAT Tec Diver

course?

2. What are the general goals of the Tec 45 and Tec 50 courses?


G. The DSAT Tec Diver course

1. The Tec 40 course is the first of three subcourses that together make up the

DSAT Tec Diver course.

a. The DSAT Tec Diver course was originally called the Tec Deep

Diver course (hence the Tec Deep Diver Manual).

b. The three subcourses, in order are the Tec 40, Tec 45 and Tec 50

courses. The names reflect the maximum qualification depth in

metres for the respective levels.

c. Completing all three qualifies you as a Tec 50 diver (formerly Tec

Deep Diver), which is a fully qualified, open circuit entry level

EANx deep decompression technical diver.

2. Tec 45 general goals are to train certified Tec 40 divers

a. to use full technical equipment.

b. to make decompression dives to 45 metres/145 feet using air or

enriched air, with accelerated decompression techniques.

c. to dive with one decompression gas with up to and including 100

percent oxygen.

3. Tec 50 general goals are to train certified Tec 45 divers

a. to make decompression dives to 50 metres/165 feet using air or

enriched air, with accelerated decompression techniques.

b. to dive with two decompression gases with up to 100 percent oxygen.


A-150 padi.com


H. Certification as a Tec 40 diver qualifies you to dive within the following limits, applying

the appropriate procedures and equipment as you’ve

been trained:

1. Dive to a maximum depth of 40 metres/130 feet using air or enriched air.

2. Make dives with up to 10 minutes required decompression.

3. Use enriched air nitrox with up to 50 percent oxygen (EANx50) during decompres-

sion to make it more conservative.

4. Although your certification qualifies you to these limits, you must also consider

other limitations, such as the environment, conditions and other factors, and apply

more conservative limits when planning dives.

5. These limits apply, even if you complete the Tec 40 using double cylinders and

other equipment required for Tec 45 and above.

Exercise, Other Delivery Content, Tec 40-1

1. The Tec Diver course (choose all that apply)

q a. consists of three subcourses.

q b. begins with the Tec 40 subcourse.

q c. no longer exists.

2. The Tec 50 course qualifies a diver to make dives

q a. with up to 50 minutes decompression.

q b. with deco stops as deep as 50 feet/12 metres

q c. to a depth of 50 metres/165 feet

q d. to a depth of 50 fathoms (300 feet).

3. As a Tec 40 diver, applying appropriate procedures and equipment as you’ve been trained,

you’re qualified to (choose all that apply)

q a. to dive as deep as 40 metres/130 feet.

q b. have up to 10 minutes required decompression.

q c. use a single gas with up to 50 percent oxygen during decompression.

How did you do?

1. a, b. 2. c. 3. a, b, c.


padi.com A-151


OtherDeliveryContent,Tec40-2


Learning Objectives


1. Why can the equipment requirements for Tec 40 be less stringent than the standardized

technical rig?

2. What are the guidelines for selecting masks, fins and snorkels for the Tec 40 level?

3. What characteristics do you look for cylinders and cylinder valves for the Tec 40 kit?

4. What is the minimum number of fully independent regulators, per diver, and how do you

configure each?

5. What type of BCDs can you use for Tec 40 level diving? Why is a tec diving harness rec-

ommended?

6. How do you choose an appropriate exposure suit for technical diving?

7. What are your options regarding weight systems, and what are the advantages and disad-

vantages of each?

8. What types of dive computers and other instruments do you need for Tec 40 level diving?

9. What types of cutting tools are appropriate for deep technical diving, and how many

should you have?

10. What are six general guidelines regarding pockets, accessories and clips you might need

when technical diving?

11. What is a “stage/deco cylinder”?

12. How do you set up a stage/deco cylinder?

13. Why might you need a lift bag/DSMB and reel on a technical dive?

14. What are suitable lift bags/DSMBs and reels, and how do you secure them on your rig?

15. What are four recommendations regarding equipment maintenance?

You should also be able to:

16. Describe the layout, arrangement and configuration of the basic Tec 40 rig, with options,

from head to toe as worn by a Tec 40 diver.

A. Tec 40 equipment requirements and the standardized technical rig

1. The technical diving community has a generally accepted open circuit

equipment configuration as worn on a technical deep dive. This standardized

technical rig employs all required equipment in a streamlined configuration

based on a philosophy that minimizes confusion and procedural error. The


A-152 padi.com


standard technical rig (backmount or sidemount) is required at the Tec 45 level

and beyond.

2. You can dive with a less stringent equipment configuration (i.e., the Tec 40 kit or

rig) within Tec 40 limits because the depth and decompression time limits are

very restricted compared to broader technical deep diving.

a. Exceeding Tec 40 limits (40 metres/130 feet and up to 10 minutes total

required decompression) is not acceptable or reasonable with the Tec 40

rig.

B. Mask, fins and snorkel

1. Generally, the mask and fins you use for recreational scuba diving in a given

environment are acceptable for the Tec 40 rig.

a. Full sized fins (appropriate to your size) are generally recommended.

b. Secure/tape loose straps so they don’t dangle and can’t slip.

c. Spring heel fins (in place of straps) are good options because they’re very

strong, nothing dangles and they don’t need adjustment and are easy to

don and remove.

2. Snorkels are optional, but generally recommended for the Tec 40 rig.

a. They allow you to breathe at the surface without using gas from your

cylinder.

b. They can be slightly cumbersome in an air sharing situation, so you may

want to carry a folding/collapsible model in your pocket.

C. Cylinders and valves

1. You generally want a high capacity cylinder as your primary cylinder with the

Tec 40 kit. This is because you use more gas on a deeper dive, and you need to

keep a larger reserve.

2. 11-12 litre/71.2-80 cubic foot cylinders are generally considered the minimum

size – larger (18 litre/100 cubic foot+ ) cylinders are preferred, but not readily

available in some locations.

a. If you opt for double cylinders, you should wear the standardized techni-

cal rig, not the Tec 40 kit.


padi.com A-153


3. The cylinder should have an H or Y valve, which allows you to have two

entirely separate regulators. In case of a failure, you can shut down the gas

to either one and still access the remaining gas with the other.

a. With Tec 40 limits, it is alternatively acceptable to have a large, main

cylinder with a pony bottle in place of an H/Y valve.

b. If you use a pony instead of an H/Y valve, it should have a capacity

of 850 litres free gas/30 cf or larger.

c. The pony usually has the same gas (EANx blend or air) as the main

cylinder. If it has a higher oxygen content, the gas must still be

breathable at the deepest planned depth (max 1.4 ata/bar), with

a margin for error.

4. The DIN (Deutche Industrie Norm) threaded system for valve apertures is

generally preferred to the yoke system in tec diving.

5. Valve caps should not be tied to valves as they commonly are in recreational

diving. Remove completely when diving.

D. Regulators

1. Because you cannot immediately surface, tec diving always requires a mini-

mum of two fully independent regulators per diver (does not count those on

stage or decompression cylinders).

2. Choose top of the line, balanced regulators for maximum reliability and per-

formance at depth.

3. Configure the regulator that goes on the right valve post with a low pressure

inflator hose and second stage with a two metre/seven foot hose.

4. Configure the regulator that goes on the left valve post with the SPG and a

second stage on a standard length hose (about 80 cm/32 inches). If using a

dry suit or a double bladder BCD system, this regulator also has a low pres-

sure inflator hose.

a. If using a pony bottle instead of an H valve, both regulators have

SPGs. In this case, the SPGs must be clearly marked or secured to

avoid any confusion.

5. Neither regulator has two second stages.

6. The DIN connection system is preferred (most DIN regulators accept adapt-

ers for yoke use).


A-154 padi.com


E. BCD and harness

1. Most BCDs with shoulder and hip D-rings (other suitable attachment hard-

ware in those locations) can be used for a Tec 40 rig. The D-rings are neces-

sary for your decompression cylinder.

2. A tec diving harness configured for a single cylinder is generally recom-

mended, though not essential, for the Tec 40 kit.

a. Tec harnesses are harnesses that mount on top of an interchangeable

BCD bladder. There are rigid plate (steel, aluminum or plastic) and

all fabric versions.

b. Tec harnesses have crotch straps, adjustable shoulder and waist

D-rings and other features suited to higher level tec diving.

c. The tec harness is recommended because you will use it when you

move on to the Tec 45 course, and because you can use a double

bladder BCD (BCD with two independent bladders and inflation/

deflation systems) so you have backup buoyancy control.

• In a decompression situation, simply dropping weights to

restore buoyancy may not be an option because you would

have too much buoyancy to maintain a decompression stop.

• Planning for BCD failure must be part of planning any

technical dive. The double bladder BCD is the simplest,

most reliable option.

• The Tec 40 rig (single cylinder) is not as negatively buoyant

as higher level tec rigs, so redundant buoyancy is not manda-

tory at this level.

F. Exposure suits

1. Choose your exposure suit based on the water temperature at depth and the

dive duration.

2. Tec dives tend to be longer than recreational dives, calling for more expo-

sure protection. You also don’t exert and generate much heat while decom-

pressing.

3. Dry suits offer the longest durations and coldest water protection.

a. They may provide ample backup buoyancy.

b. You should master dry suit diving as a recreational diver before

using a dry suit for technical dives.


padi.com A-155


• 20 dry suit dives is a conservative minimum before tec diving dry.

• In recreational diving, you only use your dry suit for buoyan-

cy control while underwater.

• In tec diving, you typically add gas to the suit to avoid a suit

squeeze and use your BCD. This means controlling the gas in

both your suit and BCD – a more complex skill to master.

4. Wet suits are adequate in warmer waters and well suited to dives within

Tec 40 limits.

a. A full 6 mm/.25 in wet suit with hood will generally handle dives up

to two or three hours (far longer than a Tec 40 dive) in water

24ºC/75ºF or warmer.

b. In a heavy rig, you need a double bladder BCD or other means for

reliably handling a BCD failure.

c. The advantage of a wet suit over a dry suit is operational simplicity –

you only need to adjust your BCD.

G. Weight systems

1. Except in very warm water requiring minimal exposure protection, you will

usually need weights even in a technical rig. A weight belt, integrated

weights or a weight harness are acceptable.

a. Some tec divers choose a metal plate harness to reduce the amount

of lead they need to wear.

2. Weight belt

a. Advantages: simple, readily available when needed

b. Disadvantages: with crotch strap, must don after putting on rig so it’s

not trapped.

3. Integrated weights

a. Advantages: no need to put on last, positioned amid rig

b. Disadvantages: must have BCD/harness system with weight system

build in; makes overall scuba rig heavier

4. Weight harness

a. Advantages: put on before scuba rig, doesn’t add to rig’s weight

b. Disadvantages: may be awkward to adjust rig so it doesn’t interfere

with quick release weight ditching.


A-156 padi.com


5. Loss of weights can be significant hazard on a decompression dive because

it can make it difficult or impossible to stay at stop depth.

a. Some tec divers put two quick release buckles on weight belts to

avoid accidental loss.

b. Another option is to wear a crotch strap over a weight belt to avoid

accidental loss. With this approach, it’s recommended that the crotch

strap have a quick release so the weights can be discarded

if necessary.

H. Instrumentation

1. You need two ways of determining your decompression requirements.

a. The simplest option is to wear two dive computers.

b. The second option is to wear a computer with depth gauge, timer and

decompression tables.

2. For Tec 40, you only need a standard air dive computer or computers.

a. An EANx compatible computer is recommended – allows you to

benefit from more bottom time with enriched air, and calculates your

oxygen exposure.

b. If you have yet to invest in your dive computers, choose models that

run multiple gases and trimix so you’ll be set for Tec 45 and beyond.

3. Arm mounted instruments (other than SPG) are generally preferred (required

at the Tec 45 level and up).

4. Mechanical SPGs are generally preferred because they’re simple and reliable.

5. Compass – You need a high quality, liquid filled model if using a standard

compass. Many newer dive computers have electronic compasses. The

compass is commonly carried in a pouch or pocket until needed.

I. Cutting tools

1. You should have a cutting tool, and ideally two (two required at Tec 45 level

up). Mount at least one where you can reach it with either hand (generally

waist/chest area).

2. Typical dive knife, dive shears, Z-knife (hook with blade), stainless folding

knives and dive tools are all acceptable.

3. Large, calf-mounted knives/tools are generally avoided in tec diving, espe-

cially cave diving and wreck penetration, because they entangle easily.


padi.com A-157


J. Guidelines for pockets, accessories and clips

1. Avoid large pocket pouches on harnesses – they cause too much bulk and

clutter.

2. Most useful pockets in tec diving are thigh pockets on your exposure suit.

3. Mount stainless steel or brass clips on accessories to clip to your BCD or

harness. Don’t mount the clips on the BCD or harness.

4. Sliding gate clips (a.k.a. dog clips) are preferred to marine snaps (swinging

gate clips), because they won’t accidentally clip to things by themselves.

5. Choose clips based on the environment – you need larger clips when wear-

ing thick gloves.

6. Using and mounting clips

a. When possible, keep accessories in pockets until needed.

b. Clip accessories well out of the way, secured so they don’t dangle.

c. Attach clips so they can break away so you can release in an emer-

gency. The simplest approach is to mount the clip via a small o-ring

or thin pull tie that breaks with a sharp tug.

K. Stage/deco cylinders

1. A stage cylinder is used to extend the deep portion of the dive. A deco

(decompression) cylinder provides gas (usually with higher oxygen content)

during decompression. They are rigged the same, so it’s common to call

deco cylinders “stages” or “stage cylinders.” The general term for both is

“stage/deco cylinder.” In context, the terms are seldom confusing.

2. Stage/deco cylinders are worn on the side under the arm, clipped at the

waist and on the chest.

3. A stage/deco cylinder never replaces one of the two regulators/valves

you need from your primary gas supply.

4. As a Tec 40 diver, you will often use a deco cylinder.

a. Some dives at this level do not need a deco cylinder, because you

have enough gas, plus your required reserve, for the entire dive

including decompression.

b. But, a deco cylinder is recommended nonetheless because it provides

extra gas capacity, plus gives you the option of switching to EANx

with a higher oxygen content for added decompression conservatism.

(More about this later).


A-158 padi.com


5. Typical stage/deco cylinder setup

a. The cylinder is typically a 4 litre/30 cf size or larger. The popular

aluminum 11 litre/80 cf has more capacity than you usually need at

the Tec 40 level, but it is commonly available and easy to handle.

It is perfectly acceptable to use – having too much gas is seldom

an issue.

b. The cylinder has a nylon rope/strap approximately 46 cm/18 in,

approximately under the valve opening, running down to a band

around the cylinder with a clip at each end. This serves as a handling

strap; the clips attach the cylinder on your BCD D-rings at the waist

and chest/shoulder.

c. The regulator has a single second stage and SPG. Hoses tuck under

inner tubing, bungee or stretch nylon straps around cylinder.

d. The second stage has break-away clip usually attached to the hose

close to where it meets the second stage.

e. The SPG may have a very short hose, or a standard length hose that

is tucked along the cylinder length.

f. It’s recommended that the clips be attached via rope or nylon so you

can cut the cylinder free if a clip jams.

g. For safety, stage/deco cylinders are always clearly marked with

the gas blend they contain, the maximum depth you can breathe

the gas (based on the oxygen partial pressure) and the diver’s

name. These markings are always large and positioned so a team

mate can read them while the cylinder is worn.

L. Lift bags/DSMBs (Delayed Surface Marker Buoys) and reels

1. You may find yourself accidentally away from your planned ascent line

(anchor/mooring line).

2. In this case, your team uses a reel to deploy a lift bag or DSMB. This gives

you an ascent reference, allows surface support personnel to track your posi-

tion, and helps you maintain your decompression stop in midwater.

3. Suitable lift bags are brightly colored, with large capacities (45 kg/100 lbs

lift) preferred. DSMBs are taller and more compact; they don’t have to have

the same lift capacities. Preferred DSMBs have one-way valves for filling,

with overpressure valves. These keep the buoy inflated even if it topples at


padi.com A-159


the surface momentarily. It is recommended that you write your name on

your lift bag/DSMB for surface support identification.

4. Lift bags are carried rolled up and tucked into special carrying pockets or

put in bungees that stow them horizontally in the small of the back. DSMBs

roll up more compactly, generally, and fit in harness/BCD pockets or thigh

pockets.

5. A suitable reel is compact with ample line to reach the surface.

6. The reel is clipped to a D-ring on the right hip.

M. Maintenance

1. You rely on your gear for life support. Therefore, maintain it according to

manufacturer recommendations.

2. Have regulators, valves, BCDs and gauges inspected and overhauled at least

annually, or more frequently for heavy use or as manufacturer specified.

3. Have anything that doesn’t appear to work normally serviced before using it.

4. Never tec dive with gear in anything but top shape and within its design

parameters. To do otherwise needlessly raises your risk of injury or death by

starting the dive with a potential problem.

N. Putting it together: basic Tec 40 rig, head to toe

1. Use a cylinder with H or Y valve in a BCD/tec harness.

2. The left side regulator has a short hose second stage. This is the secondary

regulator. It routes to the right and hangs below the chin on a bungee. The

SPG hose goes down along the cylinder; the SPG has a clip to secure it to

waist or chest D-ring (as preferred). Low pressure hose(s) feeds the dry suit

and/or backup BCD (if used). The valve is open all the way (do not close it

back a quarter turn).

3. The right side regulator has a long hose second stage. This is the primary

regulator. It is the last thing you put in place when kitting up. The hose

routes straight down along the cylinder to the hip, then up across the chest

and around the left side of the neck into the mouth. At the hip, the safety

reel lies on top of it to help keep it in place. The low pressure hose feeds the

primary BCD inflator. There is no SPG. The valve is open all the way (do

not close it back a quarter turn).


A-160 padi.com


4. If using a pony instead of an H/Y valve, the pony goes on the left side of the

main cylinder and takes the left side (secondary) regulator. In this case, the

right (primary) regulator has the primary SPG, which is clipped as described

above. The pony/secondary SPG is clipped low and behind the diver, where

it is retrievable but not easily confused with the primary. It is also clearly

marked (label, color, etc.) to easily distinguish it from the primary SPG.

5. With double bladder BCDs, the backup inflator is secured behind the diver

so that it is easy to deploy, but not easily confused with the primary (you

only use one BCD bladder at a time).

a. Some divers leave the LP hose disconnected from, but bungeed to

the backup inflator. This avoids accidental inflation (leaking inflator

valve), but is easily connected for use.

6. Instruments are ideally arm mounted (except SPG), though compact con-

soles are acceptable in the Tec 40 rig.

7. The weight system is secure, free for ditching. The backup buckle is secured if used.

8. Mask and fins are preadjusted and inspected, secured so they can’t slip out

of adjustment.


1. Tec 40 has less stringent equipment requirements than the standardized technical rig,

because the limits of Tec 40 diving keep you within recreational depth limits and a rela-

tively short decompression time.

q True

q False

2. You cannot use the same fins you use in recreational diving for Tec 40 diving.

q True

q False

3. The recommended valve type for the Tec 40 kit is

q a. the standard yoke valve.

q b. a J reserve valve.

q c. an H or Y valve, DIN system.

q d. a J or K valve, yoke system.


padi.com A-161


4. The minimum number of fully independent regulators, per diver, is

q a. 1

q b. 2

q c. 3

q d. 6

5. You can use any BCD with D-rings or attachment hardware at the shoulder/waist for the

Tec 40 kit.

q True

q False

6. Choose an exposure suit for a tec dive based on __________. (choose all that apply)

q a. depth

q b. duration

q c. temperature

q d. activity level

7. You never use a weight belt while tec diving.

q True

q False

8. For the Tec 40 level, a single computer is all the instrumentation you need.

q True

q False

9. At the Tec 40 level, you should have at least one cutting tool, but it’s recommended you

have two.

q True

q False

10. General guidelines regarding pockets, accessories and clips include (check all

that apply):

q a. mount clips to the accessories.

q b. attach clips so they can break away.

q c. thigh pockets on your exposure suit are a good option.

q d. marine (swing gate) clips are the best choice.

11. At the Tec 40 level, a stage/deco cylinder will be used to

q a. carry a decompression gas.

q b. carry gas to extend the deepest portion of the dive.

q c. both a or b.

q d. None of the above.


A-162 padi.com


12. A stage/deco cylinder is always marked with the gas it has in it, the maximum depth

and the diver’s name.

q True

q False

13. You may need a lift bag/DSMB and reel

q a. as a backup BCD.

q b. in case you lose track of your ascent point.

q c. to open a shipwreck hatch

14. A suitable lift bag or DSMB should have ample lift and be blue or gray.

q True

q False

15. Never, ever tec dive with gear that’s in anything less than top shape.

q True

q False

16. The primary regulator (choose all that apply)

q a. goes on the right.

q b. has a long hose second stage.

q c. has the primary BCD low pressure hose.

q d. goes on the left.

How did you do?

1. True. 2. False. The same fins you use recreational diving are usually suitable for the Tec

40 level. 3. c. 4. b. 5. True. 6. a, b, c, d. 7. False. A weight belt is a common option in tec

diving. 8. False. You need at least two computers, or one computer and a depth gauge,

timer and decompression tables. You should also have SPGs and a compass. 9. True. 10.

a, b, c. 11. a. 12. True. 13. b. 14. False. It should be red, yellow or some other bright

color. 15. True. 16. a, b, c.


padi.com A-163




Learning Objectives


1. What is the maximum oxygen blend you would use as the bottom gas for a dive to 40

metres/130 feet?

2. What is the maximum percentage of oxygen you will use as a Tec 40 diver?

H. As a Tec 40 diver, your maximum allowable depth is 40 metres/130 feet.

1. Using the maximum depth tables on pages 266 and 267, you find that

EANx28 is the highest oxygen content gas blend you can use at 40

metres/130 feet (PO2 = 1.4 ata/bar).

2. You may use blends with more oxygen, but at increasingly shallower maxi-

mum depths.

3. With blends that have 36 percent or more oxygen, your maximum depth is

so shallow and your no decompression time is so long that you probably

won’t have to make decompression dives at all.

I. The maximum oxygen percentage you’re qualified to use as a Tec 40 diver is 50

percent (EANx50). You will normally use this as a decompression gas (you can use

it as a bottom gas, but the maximum depth is 18 metres/59 feet – you will probably

not need to decompress on such a dive).

1. The maximum depth for using EANx50 as a decompression gas (PO2 = 1.6)

is 21m/70 ft (See the Equivalent Air Depth and Oxygen Management Tables

for 50% on pgs 274 & 288)

2. You may be carrying EANx50 (or other deco gas) to a depth deeper than

you can safely breathe it. It is critical to follow all gas handling proce-

dures to avoid accidentally switching to it at too deep a depth. You will

learn and practice these procedures beginning with Tec 40 Training Dive One.


A-164 padi.com



1. The maximum oxygen enriched air you would use as bottom gas for a dive to 40

metres/130 feet is

q a. EANx28.

q b. EANx32.

q c. EANx36.

q d. EANx50.

2. The maximum oxygen content enriched air that you’re qualified to use as a Tec 40 diver is

q a. EANx28.

q b. EANx32.

q c. EANx36.

q d. EANx50.

How did you do?

1. a. 2. d.


padi.com A-165




Learning Objectives


1. What is a “bounce” dive?

2. Why is it recommended that you switch to a higher oxygen EANx for decompression

without accelerating your decompression, and/or set your dive computer for an EANx

with less gas than actual, if making a “bounce” technical dive?

E. “Bounce” dives

1. A short dive to any depth is called a “bounce” dive.

a. The definition is imprecise – what one person calls a bounce dive

another may not.

b. It is possible to make dives within the scope of Tec 40 qualifications

that some would be consider bounce dives.

2. There are some anecdotal concerns about bounce decompression dives

a. Some people think DCS data indicate that short, deep dives with

short decompression requirements have a higher DCS risk than

would be expected based on decompression models

b. Again, definitions of “short” and “deep” and “risk” are subjective in

this context.

c. The concerns are hypothetical and not quantified, but they exist

nonetheless.

3. To minimize bounce dive concerns (at all levels):

a. Plan your dive with your computer set for air or an EANx with less

oxygen than you actually use.

b. Use a single gas computer, or if using a multigas computer, leave it

set for your bottom gas, but decompress with an EANx blend with

more oxygen.


A-166 padi.com


c. Either of these (or both) will make your decompression more

conservative.

• The required decompression time for a short, deep dives is

correspondingly short. Deco is so short there is no meaning-

ful benefit to accelerating decompression. Instead, you use

EANx to make your decompression more conservative

instead of shorter.

• It is common to extend the last deco stop two or three min-

utes as well.

Example: You dive to 40 metres/130 feet. You leave your dive com-

puter set for air, but you actually dive using EANx25 as your bottom

gas. You decompress with EANx40, but you leave your dive comput-

er (if it is a multigas model) set for air during

decompression.

d. You will plan your dives as a Tec 40 diver based on decompressing

as if using your bottom gas, but using EANx to make your decom-

pression more conservative.


1. A “bounce” dive isn’t defined precisely, but means a short dive to any depth.

q True

q False

2. To minimize bounce dive concerns (choose all that apply):

q a. set your dive computer for air or EANx with less oxygen than the gas you

actually use.

q b. accelerate your decompression.

q c. decompress with a gas that has more oxygen than you set your computer for.

q d. ascend rapidly to minimize your time at depth.

How did you do?

1. True. 2. a, c.


padi.com A-167




Learning Objectives

1. How do you use desk top decompression software to plan a decompression dive based on

a single gas, with no more than 10 minutes of decompression and a maximum depth of

40 metres/130 feet?

2. How do you use decompression software to determine your gas supply requirements?

3. What is the minimum reserve gas you should have on a technical dive?

4. How do you set your dive computer to follow the plan you made with your decompres-

sion software?

5. How does your team stay together when using dive computers to provide decompression

information?

6. What limits tell you it is time to end your dive?

7. How do you calculate turn pressure?

8. How do you account for your oxygen exposure when using a gas with a higher oxygen

content than you set your dive computer for?

9. What do you do if your desk top decompression software and dive computer differ signif-

icantly in their decompression information, or if your gas requirement calculations

appear to be off?

A. Starting with Tec 40 Practical Application Two, you’ll begin planning decompres-

sion dives using desk top decompression software.

1. Your dive planning will continue throughout the course and be the basis for

simulated and actual decompression dives you make.

2. The methods you learn also form the foundation for all your subsequent

technical dive planning. However, gas and decompression planning becomes

more complex as you go deeper and have longer decompression.

B. You will follow these basic steps:

[Note: Your instructor will take you through this, step by step, during Tec 40

Practical Application Two, followed by you and your team mates planning a dive.]

1. Launch the desk top decompression program (may be iPhone or PDA based

as long as it provides decompression and gas supply calculations, as well as

the ability to choose different gases).


A-168 padi.com


2. Set the dive characteristics and presets.

a. Select metric or imperial, open circuit (not closed circuit rebreather).

b. Working and decompression SAC rates

• You will determine your working (bottom) SAC rate during

Tec 40 Practical Application Two based on the data you gath-

ered during Tec 40 Training Dive One.

• You will gather decompression SAC rate data during Tec 40

Training Dive Two. In the meantime, use 2/3 thirds your

working rate.

• Your program may refer to SAC as RMV.

c. Select the single gas you want to use for decompression calculations

• You will probably use an EANx blend for bottom gas.

• Use the Maximum Depths tables in the Tec Deep Diver

Manual to find the highest oxygen percentage for the EANx

to your planned depth (PO2 1.4)

• Set the program for the EANx blend you will use, or for one

with lower oxygen. At the Tec 40 level, it is simplest to set

for air most of the time (21%).

• You will probably use another EANx with higher oxygen for

decompression. Do not set the program for this gas at this time.

3. Enter your planned depth and time into the program.

a. Have the computer calculate your decompression. If it is longer than

10 minutes, enter a shorter time, a shallower depth or both.

• Remember, as a Tec 40 diver, your limits are 10 minutes total

decompression time and 40 metres/130 feet maximum depth.

• For simplicity, your dives will be planned as though the

entire dive will be made at the deepest depth. At higher

training levels, however, you will learn to add planned

depth changes.

b. Enter depths/times until the total decompression time required is 10

minutes or less.


padi.com A-169


4. Use the program to determine your gas requirements based on your SAC

rates, for the planned dives.

a. Some programs do this each time they calculate decompression.

b. Most programs will show you the gas requirements before and after

calculating your reserve.

c. In technical diving, the standard minimum reserve is 33 percent (rule

of thirds), meaning that one third of all your gas is for emergencies

only. That is, the minimum amount of gas you should have on a dive

1.5 times the amount predicted for the dive and the decompression,

based on your bottom and decompression SAC rates.

d. If your program doesn’t determine reserve, simply multiply the pre-

dicted gas requirements by 1.5 to get the minimum gas volume you

should have with you on your dive.

• If you need a pony bottle or a decompression cylinder to

meet the required minimum volume, it should be at least 1/3

of your total gas supply.

• Note: At higher tec levels (Tec 45 and up), you will calculate

individual gas blends independently and have to have 1.5

times the predicted requirements for each individual gas.

Planning your decompression based on a single gas at the Tec

40 level simplifies this.

e. If the minimum gas volume is greater than the capacity of the

cylinder(s) you have will available, then plan a shorter/shallower

dive until the gas requirements (including reserve) are within the

available capacity.

f. Because divers have differing SAC rates, each diver on the team cal-

culates gas requirements for the team’s planned dive.

• The team works together with the program until arriving at a

depth and time that meets the gas supply requirements for

everyone.

• A common strategy is to plan the dive based on the highest

SAC rates (bottom and deco), with all divers carrying the

predicted amount of gas (including reserve). This is accept-

able, because it simply adds reserve for divers with lower

SAC rates.


A-170 padi.com


g. After you have a final decompression schedule with gas require-

ments that work for the team, print out the decompression schedule

and gas requirements for use at the dive site.

• If using only a single computer, print out backup tables to

laminate (or list them on a slate) and use with a timing device

and depth gauge in the event of computer failure. It is recom-

mended that you print schedules for your planned depth and

time, as well as plus and minus five minutes and plus and

minus 3 metres/10 feet (nine schedules total).

5. During equipment setup for the dive, set your dive computer(s) for the

EANx blend or air that you used in the decompression software.

a. Your actual EANx blend may have a higher oxygen content, provided

you don’t exceed a PO2 of 1.4 at your deepest depth.

b. Your decompression cylinder may have EANx50 (or a blend with

less oxygen). Do not decompress with it at a depth where the PO2

exceeds 1.6.

c. These gases with higher oxygen content simply make your decom-

pression more conservative.

d. During the dive, you and your team mates may have slightly differ-

ent decompression schedules due to slight variances in your depths,

as well as differences in your dive computer’s decompression models.

• To stay together, the team stays at each stop until all computers

clear all divers to ascend to the next stop or surface.

• If using tables (back up situation), team stays at each stop

until all computers clear all divers to ascend, or for the table

stop time, whichever is longest.

6. Limits that end the dive.

a. In technical diving, your dive ends when anyone on your dive team

reaches any of the following, whichever comes first:

• you reach the planned bottom time (what you used in the

decompression software)

• your or a team mate’s dive computer shows 10 minutes

decompression time required (or less if the planned decom-

pression was less)


padi.com A-171


• It is important to turn the dive with the planned

decompression time showing, even if the bottom time

is less than planned and the required decompression is

still less than 10 minutes, because your decompression

gas volume requirement is based on the planned

decompression time.

• you or a team mate reaches turn pressure on your gas supply

7. Turn pressure is the reading on your SPG that indicates it is time to head up.

It is calculated based on the cylinder pressure of the gas volume your soft-

ware predicts you’ll use on the bottom. Knowing your turn pressure and

having it written on a slate assures that you head up with the gas for decom-

pression and reserve intact.

a. Almost all software will tell you the required gas for all individual

gases, but many do not tell you how much you use on the bottom, or

calculate turn pressure.

b. To determine your turn pressure, you may therefore have to do so

with a calculator and the tables in the Tec Deep Diver Manual.

c. You will use turn pressure formulas, as well as what you already

learned about SAC and actual gas supplies in Tec 40 Knowledge

Development One.

• Note: For simplicity, treat your descent as time on the bot-

tom. This gives you a slightly higher reserve.

d. Formulas:

• Metric: Turn pressure = start pressure – (bottom volume ÷

cylinder capacity)

• Imperial: Turn pressure = starting pressure – (bottom volume

÷ baseline)

e. Examples

Metric example:

Your working SAC rate is 19 litres per minute. You plan a dive to 40 metres

for 10 minutes. Your decompression software shows that using an 11 litre

cylinder, working pressure 205 bar, and a 9 litre deco cylinder will provide

the gas volume you need. By what pressure should you start your ascent?


A-172 padi.com


First, find your bottom volume.

Bottom volume = minutes X SAC X conversion factor

Bottom volume = 10 X 19 X 5.2

Bottom volume = 988 litres

Assuming your 11 litre cylinder is full (205 bar), then:

Turn pressure = 205 – (988 ÷ 11)

Turn pressure = 115 bar

To manage your gas appropriately, you should begin ascending when or

before your SPG reaches 115 bar.

Imperial example.

Your working SAC rate is .8 cf per minute. You plan a dive to 130 feet for

10 minutes. Your decompression software shows that using an 80 cubic foot

cylinder, working pressure 3000 psi, and a 65 cubic foot deco cylinder will

provide the gas volume you need. By what pressure should you start your

ascent?

First, find your bottom volume.

Bottom volume = minutes X SAC X conversion factor

Bottom volume = 10 X .8 X 4.9

Bottom volume = 39.2 cubic feet

Next, find the baseline for an 80 cubic foot cylinder. Recall that to get the

baseline, you divide the working capacity by the working pressure

Baseline = cap ÷ working pressure

Baseline = 80 ÷ 3000

Baseline = .0267


padi.com A-173


Assuming your 80 cubic foot cylinder is full (3000 psi), then:

Turn pressure = 3000 – (39.2 ÷ .0257)

Turn pressure = 1474 psi.

To manage your gas appropriately, you should begin ascending when or

before your SPG reaches 1474 psi.

f. Note that in both examples that your deco cylinder is required to

meet the required reserve (rule of thirds).

C. Oxygen exposure calculations

1. If your dive computer was set for air or EANx with less oxygen than your

actual bottom gas and/or you switched to a higher oxygen decompression

gas for conservatism, you have to account for your oxygen exposure after

the dive, because your dive computer didn’t know how much oxygen you

actually had in your cylinder(s).

2. After the dive, use desktop software and enter the dive as you actually made

it – actual depths, times and gases used. Record your OTUs and CNS clock

for planning subsequent dives.

D. Repetitive dives

1. Plan repetitive dives as you did the first dive, but recall that you must enter

the first dive data and your surface interval so the program can account for

residual nitrogen.

2. When planning a repetitive dive, enter the actual dive as made. You may

also use the previous dive as planned if it yields a more conservative repeti-

tive dive plan.

3. If OTUs or CNS could approach their maximums – unlikely within Tec 40

limits, but possible if you make several repetitive dives – after planning

your dive based on a single gas, enter the planned depths, times and stops

based on the actual gas blends to make sure you will remain within

oxygen limits.


A-174 padi.com


E. Making software line up with your dive computer

1. After a few decompression dives, you may find that your decompression

software is more conservative than your dive computer, or vice versa.

a. Be sure your backup computer and/or your team mate’s computers

are similar to your computer to rule out a problem with your computer.

2. If you don’t spend the majority of the time at the deepest depth, your dive

computer would be expected to be less conservative than your software,

because it calculates the slower nitrogen absorption. Don’t make any adjust-

ments on this account.

3. If you do spend the majority of the time near the deepest depth, there may

be some difference in the required stops and some variation in the total

decompression time due to minor differences in the decompression models.

This is normal.

4. If there is a large difference between your decompression software and your

dive computers (enough to substantially throw off gas supply calculations

etc.), contact the software author and/or the dive computer manufacturer.

You can adjust safety factors above the default settings to make software

more conservative, but do not make it less conservative unless advised to do

so by the software manufacturer.

5. Assuming no unforeseen emergencies, you should surface from a dive with

your reserve gas supply intact. If you have substantially more or less gas:

a. First, confirm your working and decompression SAC rates. Adjust

your SAC rates in the software if necessary.

b. If your SAC rates are accurate and you’re coming up with a bit less

gas than you should, it is typically that your software predicts less

decompression than does your computer.

c. Check your decompression software setting and adjust it so it is

more conservative and predicts a bit longer decompression.

d. If the decompression seems to be in line (close match between your

dive computer and the software), it may be how the software calcu-

lates gas use. Increase your SAC rate setting even if that makes it

high compared to your calculations.

e. Do not adjust anything if you have too much gas, unless the surplus

is extreme. Too much gas is seldom a problem.


padi.com A-175



1. At the Tec 40 level, the recommendation is that you use EANx for your bottom gas and

set your decompression software dive

q a. for the gas you’re using.

q b. for an EANx blend with more oxygen.

q c. for at least two different gases.

q d. for air or an EANx blend with less oxygen.

2. To determine your gas supply requirements, you must enter your _________ into the

software.

q a. decompression profile

q b. SAC rates

q c. bottom gas

q d. dive computer model

3. The minimum gas reserve you should plan for on a technical dive is ________ of your

total gas supply.

q a. a quarter

q b. a third

q c. half

q d. two thirds

4. At the Tec 40 level, you set your dive computer to follow the plan you made with your

decompression software by setting it for the EANx blend you used for your decompres-

sion planning with the software.

q True

q False

5. When using computers to provide decompression information, the team stays together.

All divers stay at each stop until all computers clear all divers to ascend to the next stop.

q True

q False

6. When you or a team mate reaches any of the following, you should begin your ascent

(choose all that apply):

q a. your planned bottom time

q b. a dive computer shows 10 minutes decompression required

q c. you have a decompression stop at 18 metres/60 feet

q d. turn pressure on your SPG


A-176 padi.com


7. You calculate turn pressure by determining how much cylinder pressure you would use

for the volume software predicts you will consume on the bottom.

q True

q False

8. To account for your oxygen exposure when using a gas with a higher oxygen content

than you set your dive computer for

q a. you needn’t do anything because the difference is negligible.

q b. you need to dive with a third and fourth dive computer set to the actual content.

q c. you enter the actual dive with the actual gases into your software.

q d. All of the above.

9. If your gas requirement calculations appear to be off, your first step is to confirm your

working and decompression SAC rates.

q True

q False

How did you do?

1. d. 2. b. 3. b. 4. True. 5. True. 6. a, b, d. 7. True. 8. d. 9. True


padi.com A-177




Learning Objectives


1. What are Oxygen Tolerance Units (OTUs)?

2. How do you use OTUs to manage oxygen exposure?

3. How do you use the CNS “clock” to manage oxygen exposure?

4. What is the basis for CNS clock surface interval credit?

5. Why may you choose an EANx blend than has a PO2 less than 1.4 at the working depth

for a particular dive?

A. As you already learned, you need to manage your oxygen exposure when using

EANx (and later oxygen as a Tec 45 diver) to avoid pulmonary and CNS oxygen

toxicity.

1. Recall that your primary prevention of CNS toxicity is in keeping your oxy-

gen partial pressure below the critical thresholds of 1.4 (working part of the

dive) and 1.6 (decompression at rest).

2. Because it is a biochemical process, there must be an exposure-time rela-

tionship involved with the onset of CNS toxicity. However, there are so

many other physiological variables involved that, for practical purposes, the

relationship is useless for reliably predicting CNS toxicity.

3. Pulmonary oxygen toxicity does have a useful time-exposure relationship

that allows reliable predictions.

a. OTUs (Oxygen Toxicity Units or Oxygen Tolerance Units, depend-

ing upon the reference) and the “CNS clock” both help you prevent

pulmonary oxygen toxicity.

b. As a Tec 40 diver, pulmonary oxygen toxicity is highly unlikely, but

possible if you make several dives in a short period using EANx

with high oxygen (like EANx50).

B. OTUs

1. OTUs are units that measure your oxygen exposure as a dose. A given time

at a given PO2 yields a certain number of OTUs based on a simple mathe-

matical equation.


A-178 padi.com


2. At the Tec 40 level, as you know, you use your desk top decompression

software to calculate your OTUs.

a. You enter the actual gases you use (EANx blend) for your bottom

depth and time, and for your decompression stops and times.

3. OTU limits vary depending upon how much diving you’re doing.

a. The Oxygen Tolerance Units Exposure Limits table in the Appendix

of the Tec Deep Diver Manual shows you the limits based on the

number of days diving.

b. The Total OTUs for Mission is the limit for all OTUs together over

the given number of days.

c. The Average OTUs per day is the maximum allowed in a single day.

d. Note that at 11 days on, the daily limit is 300 OTUs.

• Many tec divers use 300 OTUs per day as the limit, even if

diving for fewer than 11 days. This keeps things simple and

conservative.

• You’ll find that 300 OTUs covers a lot of diving – this is a

very workable approach even at higher tec diving levels.

e. Check your OTUs with your desk top decompression software after

each dive.

C. CNS clock

1. It seems somewhat redundant to calculate the “CNS clock” and OTUs, but

this is the state of practice in tec diving.

2. As you know, you calculate CNS clock with your desk top decompression

software. The CNS clock is expressed as a percent of the allowable expo-

sure – so it should not exceed 100 percent.

a. Most software calculates OTUs and CNS clock simultaneously.

3. There is oxygen surface interval credit for the CNS clock.

a. Between dives, your body begins reversing the effects of oxygen

exposure. This means there is potential for crediting time at the sur-

face.

b. The basis for CNS surface interval credit is hospital patients under-

going long term oxygen exposure. The system has a good field

record with use.

c. Most desk top decompression software will credit your CNS expo-

sure when you plan repetitive dives.


padi.com A-179


d. The system has variations, so different decompression programs may

give somewhat different results. You can also reference the CNS

Surface Interval Table in the appendix of the Tec Deep Diver

Manual.

e. Note that there is no surface interval credit for OTUs.

4. As always, stay well within CNS and OTU limits.

D. Oxygen exposure and gas blend choice

1. As you’ve learned, the “ideal” blend for a given dive is the one with a PO2

near 1.4 at the maximum depth. This is based on the assumption that you

want the maximum possible oxygen so you have the minimum nitrogen

(and/or helium as a trimix diver) possible.

2. However, previous oxygen exposure or plans for additional dives may affect

this.

3. To keep oxygen exposure well within limits, you may choose an EANx

blend with a PO2 less than 1.4, even if it means a shorter bottom time or a

longer decompression time. This also keeps you well within PO2 limits.

4. As you gain experience and increase your training as a tec diver, it becomes

increasingly important to consider prior and planned dives when determin-

ing your OTUs and “CNS clock” exposure.


1. Oxygen Tolerance Units are units that measure your oxygen exposure as a dose.

q True

q False

2. To use OTUs, (choose all that apply):

q a. use software to calculate OTUs based on actual depths, times and gases.

q b. stay within the limits of the Oxygen Tolerance Units Exposure Limits table.

q c. never exceed 100 OTUs per day.

q d. use your software to calculate OTU surface interval credit.

3. To use the “CNS clock,” (choose all that apply):

q a. use software to calculate CNS clock percent based on actual depths, times and gases.

q b. you don’t exceed 100 percent.

q c. stay well within limits.

q d. use your software to calculate CNS surface interval credit.


A-180 padi.com


4. The basis for the CNS clock surface interval credit is extensive testing with military divers.

q True

q False

5. Even if it were available, you may choose an EANx blend with a PO2 less than 1.4 at

the working depth to

q a. make your decompression more efficient.

q b. reduce oxidative wear on your equipment.

q c. decrease narcosis.

q d. manage your oxygen exposure over several dives.

How did you do?

1. True. 2. a, b. 3. a, b, c, d. 4. False. The basis for the CNS clock surface interval credit is

data from hospital patients undergoing long term oxygen exposure. 5. d.


padi.com A-181




Learning Objectives



2. As a Tec 40 diver, what should you do if you have a delay during your ascent?

3. As a Tec 40 diver, what should you if you miss a decompression stop?


5. As a Tec 40 diver, what should you do if you run out of gas?

A. This section discusses handling some emergencies within the context of Tec 40

equipment requirements and limits.

1. The same emergencies can be more serious and more complex to handle for

longer, more complex technical dives.

2. This is another important reason to stay within the limits of your training

and equipment.

B. Exceeding your planned depth and time.

1. This should be a rare situation caused by unusual circumstances (if you can’t

control your depth under normal circumstances, you’re not ready to tec dive).

2. Immediately ascend and consult your computer. Your allowable dive time

will likely be much shorter than you planned.

3. If you exceeded your depth significantly and/or for more than a minute, end

the dive immediately.

C. Delay in ascent

1. At the Tec 40 level, a delay in your ascent is not usually a major issue.

2. Your dive computer will calculate the changes in your required decompres-

sion, if any.

3. If using a backup table (computer failed), it is not critical if the delay is

short (2-3 min or less)

a. Don’t count the delay as decompression time.

b. Extend your last stop as much as practicable, gas allowing.


A-182 padi.com


D. Missed decompression stop

1. At the Tec 40 level, this is most likely to be caused by failure to control

buoyancy.

2. If you can, redescend and complete the stop, plus one minute, then finish

decompression according to your dive computer.

3. If you can’t redescend, stay at the next stop for the combined time of both

stops. Extend your last two stops (if two or more) by 1.5 what your comput-

er requires, and/or as long as you can with the gas you have.

4. Some dive computers will lock up until you redescend to below the depth of

a required stop. They provide no information in the event that you can’t

return to your deeper stop depth. If you have such a computer or computers,

(see the manufacturer’s instructions), you should have your planned decom-

pression schedule with you (on a slate, backup tables, etc.) in case of this

kind of emergency.

E. Omitted decompression

1. Omitted decompression is similar to a missed stop, but involves missing all

required stops and coming all the way to the surface.

2. The risk of DCS is higher than normal, but at the Tec 40 level it should not

be excessive if:

a. you’re using an EANx blend with more oxygen than you’ve set your

dive computers for.

b. you’ve completed most of your decompression using an EANx with

an even higher oxygen content.

3. If you omit decompression for 6 metres/20 feet or less (most likely within

Tec 40 limits), have no symptoms and can return to stop depth in less than a

minute, decompress according to your computer, then extend the last stop as

much as possible.

4. If you omit decompression for 6 metres/20 feet or less (most likely within

Tec 40 limits), have no symptoms and return to stop depth in more than a

minute, extend your 6 metre/20 foot stop by 1.5 times what the computer

requires, and extend the last stop as much as possible.

5. If you omit decompression from deeper than 6 metres/20 feet, return to the

first stop depth. Complete that stop up to and including the 12 metre/40 foot

stop, then extend all subsequent stops by 1.5 times the required decompression.


padi.com A-183


6. If you can’t return to depth (no gas available, for instance), breathe oxygen,

remain calm and monitor yourself for DCS symptoms.

7. Some dive computers will lock up if you omit decompression. Others lock

up after a given period (typically a minute), after which they provide no

decompression information. If you have such a computer or computers, (see

the manufacturer’s instructions), you should have your planned decompres-

sion schedule with you (on a slate, backup tables, etc.) in case of this kind

of emergency.

F. The TecRec Emergency Procedures Slate summarizes the procedures for delayed

ascents, missed decompression and omitted decompression. It is recommended that

you carry this slate with you on tec dives.

G. Running out of gas

1. Should be unlikely at the Tec 40 level if you plan your gas supplies correct-

ly and follow the reserve rules.

a. Having a deco cylinder with more than ample gas makes this even

less likely.

2. Increased SAC rate due to exertion is not usually an issue, because you hit

turn pressure sooner, which means a shorter dive time and less decompres-

sion.

3. If you run low on gas in a deco cylinder, switch to your back gas. As a Tec

40 diver, all your decompression should be based on using that gas or ideal-

ly, on one with lower oxygen content.

4. You can share gas with team mates and/or support divers.

5. Generally, if gas termination interferes with your decompression, decom-

press as long as you can, as best as you can. The more you decompress, the

lower your DCS risk. However, do not run out of gas. DCS is serious but

has a high likelihood of successful treatment. Drowning does not.


A-184 padi.com



1. If you exceed your planned depth and time, as a Tec 40 diver you should consult your

computer and be prepared to end your dive sooner than planned.

q True

q False

2. If you have a delay during your ascent, as a Tec 40 diver (choose all that apply)

q a. you should decompress for 1.5 times what your computer says.

q b. you should decompress for 3 times what your computer says.

q c. continue to decompress according to what your computer says.


3. If you miss a decompression stop, as a Tec 40 diver (choose all that apply)

q a. you should redescend, complete the stop plus one minute, then finish decompres-

sion according to your dive computer.

q b. surface and seek immediate recompression.

q c. descend to 12 metres/40 feet and extend all stops by 1.5 times what you comput-

er requires.

q d. you may need to refer to your written decompression schedule if your computers

would lock up.

4. If you omit decompression, what you do depends upon how deep your stops were when

you had the omission, and how fast you can return to stop depth.

q True

q False

5. If you run out of gas, as a Tec 40 diver your options may include (choose all that apply)

q a. switching back to back gas.

q b. sharing with a team mate or support diver.

q c. decompressing for as long as possible with what you have to minimize DCS risk.

How did you do?

1. True. 2. c. 3. a, d. 4. True. 5. a, b, c.


padi.com A-185




Learning Objectives


1. Why is the standard practice to use two multigas dive computers on the dive, and to plan

with desk top decompression software?

2. Why are DSMBs replacing lift bags in many tec diving situations?

3. Why has failure of quick releases on harness shoulders proved not to be a serious issue?

What would you do if it were to happen?

4. What is perhaps the most common weighting error in tec diving?

5. Why is backup buoyancy critical in most open water, open circuit technical diving?

6. What are the problems with trying to use a lift bag or DSMB as a backup buoyancy system?

7. What is the policy of virtually every lift bag and dry suit manufacturer with respect to

backup buoyancy?

8. Why is the redundant (double bladder) BCD the most realistic approach to providing

backup buoyancy control?

A. The standard of practice in deep decompression tec diving is to use multigas dive

computers during the dive, with decompression software for overall planning. You

may use a single gas computer and/or depth gauge and timer with tables in this

course, but this is the recommended approach. There are several reasons why:

1. Multigas computers now handle up to seven gas mixes (including trimix),

and also calculate CCR (closed circuit rebreather) diving, making them suit-

ed to your future as well as present tec diving.

2. A multigas computer maximizes your options in an emergency, allowing

you, for example, to switch to a lower oxygen gas (even back gas) should

you lose or exhaust your primary deco gas.

a. Some of the newest models allow you to enter entirely new gases

during the dive and recalculate your decompression. This provides

more options in an emergency.


A-186 padi.com


3. Many multigas computers have PC interfaces, allowing you to adjust stop

depths, conservatism factors, etc. Some let you choose the decompression

model you prefer.

4. Multigas computers track your actual dive profile, adjusting your decom-

pression requirements based on your actual dive. This makes it easier to

adjust to circumstances. Example: You accidentally exceed your planned

depth slightly; you leave the bottom sooner based on your computer so that

your decompression time is the same as planned, keeping you within your

gas plan.

5. With a multigas computer, you can choose to decompress based on a single

gas and switch to a higher oxygen gas for added conservatism (as you

learned to do as a Tec 40 diver). Should circumstances require (emergency),

however, you can switch to accelerated decompression to get to the surface

faster with less gas used.

6. You still use deco software to plan the dive – oxygen exposure, decompres-

sion and gas requirements. Use the computer within the dive you plan.

7. Multigas computers are more sophisticated than single gas, so they’re more

complex to use. But, they are not difficult to use and getting easier.

B. DSMBs (Delayed Surface Marker Buoys) are replacing lift bags in many tec diving

situations.

1. DSMBs stand higher in the water, making them preferred for rough condi-

tions.

2. DSMBs are more compact on your rig, making them popular when used as

an emergency alert only.

3. DSMBs have no-spill designs (though several lift bags have these, too,

now), so accidentally losing tension on the line isn’t likely to result in a

spilled buoy.

4. The highest capacity DSMBs are essentially tall, thin lift bags and work

well for drift decompression.

5. Several types of DSMBs (and lift bags) have LP inflation ports that allow

you to fill them with an LP inflator hose, away from your body or mouth,

without using a second stage. This minimizes the chance of regulator freeze,

as well as minimizing reel tangle issues.


padi.com A-187


C. At one time, some people thought failure of shoulder quick release buckles on tec

harnesses would be a serious issue. This hasn’t proven true.

1. Quick release buckles are designed to withstand hundreds of kg/lbs direct

stress. This explains why stress failure is virtually unheard of.

2. Were the release to fail, you would only have to pass the lower part of the

harness strap through the D-ring on the upper part and tie it.

D. Weighting

1. Proper weighting and adequate backup buoyancy remain two areas com-

monly addressed inadequately in open circuit technical divers.

2. Perhaps the most common weighting error in tec diving is under weighting.

a. Proper weighting means you’re able to maintain your final stop

depth with nearly empty back cylinders and either no or near-empty

deco cylinders – this is what would happen if you had a major prob-

lem forcing you into a long deco using your gas reserve, and/or

decoing on back gas.

b. If you were not weighted for this, you face a high DCS risk, because

you would not be able to remain at stops.

c. As an example, a properly weighted tec diver wearing high capacity

doubles and two deco cylinders will be about 14 kg/30 lbs negatively

buoyant at the start of a dive, and 4.5 kg/10 lbs or more negative at

the end if dive goes as planned.

d. In this example, inadequate weighting would mean that in an emer-

gency situation, besides the original problem, you also have to deal

with between 4.5 kg/10lbs and 14 kg/30 lbs positive buoyancy while

trying to decompress.

E. Backup buoyancy is critical in most open water, open circuit technical diving

because a diver is substantially negatively buoyant throughout the dive.

1. Failure of the primary BCD without a backup leaves no alternative but to

drop equipment (deco cylinders, weights, etc.). This can make the situation

worse if the diver must discard deco gases to attain buoyancy.

2. Discarding gear may result in too much buoyancy. If the diver is already in

deco, the ability to decompress effectively becomes compromised, growing

worse as the diver consumes gas.


A-188 padi.com


3. There is a high likelihood of surfacing with omitted decompression if the

diver cannot maintain stop depths, or lacks the required decompression

gases, or both.

4. A dry suit may work as a backup buoyancy device.

a. This is primarily an option when the dive will be relatively short and

shallow, with short decompression – the gas requirement is low, so

the diver is not substantially negatively buoyant (such as when using

aluminum cylinders).

b. Limited option – most dry suits will not hold more than small

amount of excess gas. Beyond a certain point, it escapes through

neck/wrist seals.

c. Several manufacturers caution against inflating their dry suits to gain

large amounts of buoyancy because of zipper failure issues.

d. A large volume of expanding gas is harder to control in a dry suit.

e. With deeper/longer tec dives, backup buoyancy control other than

the dry suit is generally necessary.

5. Some have advocated using a lift bag or DSMB as a backup buoyancy

device. This has several problems:

a. DSMBs and lift bags are not designed as buoyancy devices and are

difficult to control in that role.

• They are even more difficult to control while trying to per-

form gas switches, handle a gas shutdown, etc.

• Even if learned and practiced, it is not a skill one would

expect a diver to perform reliably in a real failed BCD emer-

gency over the course of a real decompression. If it has not

been practiced at all, it would be especially difficult.

• DSMBs/lift bags do not provide a realistic buoyancy system

for positive buoyancy at the surface after completing decom-

pression.

• Using a DSMB/lift bag as back up buoyancy would require

the diver to hold on to the bag while dealing with other tasks,

or it would have to be clipped to the harness. Either would

compromise safety.

b. If the DSMB/lift bag is used for backup buoyancy, then it is not

available to send to the surface.


padi.com A-189


c. Sending the DSMB/bag to the surface and hanging on the line for

buoyancy is not a good option either.

• In all but flat seas, this will cause the diver to rise and fall,

compromising the quality of the decompression.

• Once sent up, there is no way to adjust the bag’s buoyancy.

• It is not a technique that transfers well to other environments.

• Stress on the line and reel is a major issue. For this to be reli-

able, the diver would need to carry much heavier line and a

larger reel than most tec divers prefer.

d. Trying to use a lift bag or DSMB as a backup buoyancy system

unnecessarily complicates an emergency situation, and provides

inadequate benefit.

6. It’s worth noting that no dry suit manufacturer and no lift bag manufacturer

sanctions the use of their products as tec diving backup buoyancy devices.

Some specifically warn against it.

7. The redundant (double bladder) BCD is the most realistic approach to pro-

viding backup buoyancy control.

a. They are designed for the job and endorsed by the manufacturers.

b. They are used the same way as your primary BCD – a well practiced

skill you use on every dive, exactly what you want in an emergency

situation.

c. They are applicable to virtually all dive environments.

d. Other than a slightly higher investment, there are no meaningful

drawbacks.

e. They are the only real option for open water tec diving in a wet suit.


A-190 padi.com



1. Multigas computers have become the standard of practice in tec diving because (choose

all that apply)

q a. they handle multiple gases and CCR diving.

q b. they maximize your options in an emergency.

q c. their decompression models are newer than those in single gas computers.

q d. they are smaller than single gas computers.

2. DSMBs are replacing lift bags in many tec diving situations because (choose all that apply)

q a. they don’t stick so far up into the wind.

q b. they are more compact on your rig.

q c. they have no-spill designs.

q d. some have special inflation systems.

3. It is unlikely that a quick release on your harness shoulder would fail, but if it did, you

would only need to tie off the loose end.

q True

q False

4. Perhaps the most common weighting error in tec diving is

q a. under weighting.

q b. over weighting.

q c. neutral weighting.


5. Backup buoyancy control is critical in open water, open circuit tec diving because if

you’re properly weighted and your primary BCD fails, you risk being unable to decom-

press adequately.

q True

q False

6. Problems with trying to use a lift bag or DSMB as a backup buoyancy system include

(choose all that apply)

q a. it is a complex skill with low reliability for use under stress after disuse.

q b. it is difficult to conduct that skill and other complex skills at the same time.

q c. hanging from a floating DSMB/lift bag may compromise the quality of decom-

pression.

q d. hanging from a floating DSMB/lift bag requires a heavier line/reel than tec divers

like to use.


padi.com A-191


7. Several manufacturers endorse the use of the lift bags/DSMBs are emergency backup

buoyancy devices.

q True

q False

8. The redundant (double bladder) BCD is the most realistic approach to providing backup

buoyancy control because (choose all that apply)

q a. they were designed specifically for this purpose.

q b. you use them exactly like you use your primary BCD – a practiced skill.

q c. it is applicable to almost all dive environments.

q d. other than a slightly higher cost, it has no meaningful drawbacks.

How did you do?

1. a, b. 2. b, c, d. 3. True. 4. a. 5. True. 6. a, b, c, d. 7. False. 8. a, b, c, d.


A-192 padi.com



padi.com A-193




Learning Objectives

By the end of this section, you should be able to answer this question:

1. Why may you set a multigas computer for gas blends you don’t plan to use on a dive?

L. More on using multigas computers in emergency situations

1. You do not have to use a gas just because you set your multigas dive com-

puter for it.

2. Dive computers that support a large number of gases can be set for gases

you don’t plan to use, but that would be available for use in an emergency.

This gives you more gas options in the event of an emergency.

a. Example: Deco gases used by another team that will be diving along

with your team may be different from your team’s, but available for

sharing.

b. Example: Air is readily available in many dive environments, so

support divers could bring it for decompression use if nothing else

were quickly obtainable.

3. The main drawback to having your multigas computer set for gases you

don’t plan to use is that you have to be sure you don’t select one of the con-

tingency gases by accident.

4. Some of the newest computers will allow you to enter a new gas during the

dive should you need to do so in an emergency situation. The computer can

then calculate your decompression accordingly.


1. You might set a multigas computer for gas blends you don’t plan to use during a dive so

your computer can calculate your decompression with them in an emergency situation.

q True

q False

How did you do?

1. True.


A-194 padi.com



padi.com A-195




Learning Objectives


1. What are your two options for conducting deep stops?

2. What is the current thinking regarding deep stops?

3. What approach to deep stops seems to be the most prudent?

G. More on deep stops

1. There are two primary options for conducting deep stops.

a. The first is to use a conventional dissolved gas decompression model

and then add deep stops as discussed previously and in the Tec Deep

Diver Manual.

b. The second is to use a decompression model that inherently stops

you deeper than other models. Most “bubble” models fit into

this category.

2. Although deep stops had a lot of anecdotal support at one time, the current

thinking based on US Navy Experimental Diving Unit research is that they

may not be as beneficial as once thought.

a. The USN compared a bubble model and conventional dissolved gas

model on manned test dives. Dives were to the same depth for the

same duration with the same decompression time distributed over a

deep stops (bubble) schedule and a conventional (dissolved gas)

schedule.

b. The tests were terminated due to an unacceptable DCS rate in

subjects decompressed with the bubble schedule.

3. Other data are less conclusive.

a. Some no stop diving tests find a minor benefit to deep stops.

b. Many divers have been using bubble models without

difficulties.

c. Deep stops and bubble models are common practices widely used in

the tec community, again, without widespread

problems.


A-196 padi.com


4. The prudent approach to deep stops at the moment seems to be:

a. Use a conventional dissolved gas model and add deep

stops as you learned. The deep stops will lengthen your shallower

stops.

b. If you wish to use a decompression bubble model, choose one that is

well supported by human test data.

c. Whatever model you use, stay well within limits and pad your decom-

pression to make it conservative. Don’t be in a hurry to leave your last

stop – extend it beyond the required time.

d. Stay up to date on the latest findings in decompression research.

Know your sources – just because someone says something on an

internet forum doesn’t make it true.


1. Your two options for deep stops include (choose all that apply)

q a. using a deep stops bubble model.

q b. adding deep stops to a bubble model.

q c. using a conventional dissolved gas model.

q d. adding deep stops to a conventional dissolved gas model.

2. The current thinking on deep stops is

q a. they are unquestionably beneficial.

q b. they are unquestionably without benefit.

q c. there is some doubt about whether they’re as beneficial as once thought.

3. To use deep stops prudently (choose all that apply)

q a. use a conventional model, add deep stops and complete the extra deco they add.

q b. if you use a bubble model, use one well supported with human test data.

q c. use any model conservatively.

q d. stay informed about the latest findings in decompression theory.

How did you do?

1. a, d. 2. c. 3. a, b, c, d.


padi.com A-197




Learning Objectives


1. What are the options and considerations for long hose gas sharing during the decom-

pression phase of a technical dive?

D. Sharing gas with the long hose is usually a procedure that closes the gap between

when the victim loses the gas supply and reaches another independent gas supply or

the surface.

1. On a deco dive, if there are stops before the first gas switch, it may be nec-

essary to supply gas to the affected diver on those stops.

2. One advantage of a three person team is that it provides two people to help

the one – both divers can provide gas to the victim at various intervals so

that neither one has a severely depleted supply.

3. At the first gas switch, the victim can usually dive independently through

the rest of the dive.

a. At the Tec 50 level, air breaks will not usually be needed until after

the second gas switch; the affected diver can usually break on the

lower oxygen deco gas.

b. If the first deco gas is EANx50 or higher, however, the diver may

need to share gas for air breaks.

c. At the surface after completing decompression, the victim will usual-

ly breathe from a deco cylinder while orally inflating the BCD, but

it’s a good idea for a team mate to stay ready with the long hose until

the victim is out of the water.


A-198 padi.com



1. Considerations and options for long hose gas sharing on a decompression dive include

(choose all that apply):

q a. the depth at which the victim switches to the first deco gas.

q b. whether the victim will need long hose gas sharing for air breaks.

q c. whether the long hose is oxygen compatible.

q d. being ready to provide assistance at the surface after completing

decompression.

How did you do?

a, b, d.


padi.com A-199




Learning Objectives


1. What are three reasons you may want to “tec dive” in a pool or shallow water?

C. Practice, practice, practice

1. Tec diving involves a lot of motor procedures. A motor procedure is a series

of motor skills that you carry out in sequence in response to a need of some

kind (routine or emergency).

2. Motor skills erode with disuse, but usually refresh quickly with practice.

3. New situations may call for creating new motor procedures.

4. As a tec diver, you may find it a good idea to practice your tec diving skills

in a pool or other shallow, no stop dive situation for these reasons:

a. To refresh your skills – You already know you need to do this as a

recreational diver if you’ve not been active in awhile. Even if you’re

active as a tec diver, however, you may want to refresh seldom-used

emergency skills. These may include long hose drills, send up lift

bags/DSMBs, drift decompression, etc. – whatever skills you may

need in an emergency, but have not actually practiced in quite a few

dives.

b. To extend your skills – You may need to apply what already know in

a new situation; practicing first may help. For example, if you may

have to don and remove deco cylinders in reduced visibility and

heavy surface chop while hanging onto a current line, it may be

worth practicing doing this with your face entirely underwater and

your eyes closed, while hanging onto a line.

c. To invent mission specific skills – Your dive plan may call for doing

something highly specific, such as recovering a lost object. If you

don’t know the best way to rig the object for recovery, you may want

to invent the procedure using a duplicate of it in shallow water.


A-200 padi.com



1. Reasons you may want to “tec dive” in a pool or shallow water include (choose all that

apply):

q a. refreshing your skills.

q b. teaching yourself to cave dive.

q c. to extend your skills to specific situations.

q d. to invent mission specific skills.

How did you do?

a, c, d.


padi.com A-201




Learning Objectives


1. What is trimix?



A. At depths beyond 30 metres/100 feet, trimix is increasingly advantageous.

1. Trimix is a blend of oxygen, helium and nitrogen.

a. Much as enriched air nitrox is abbreviated “EANx,” trimix is abbre-

viated “TMx.”

b. Trimix nomenclature is to label a blend with the oxygen and helium

content. Example: TMx10.5/50 is 10.5 percent oxygen, 50 percent

helium, balance nitrogen

2. The prevailing view is that you use trimix for open water dives deeper than

50 metres/165 feet .

a. Deeper than 40 metres/130 feet, the prevailing view is that trimix is

required for overhead environments or complex open water environ-

ments.

b. Although using air as deep as 50 metres/165 feet for open water div-

ing has a long-standing record of being acceptable, the trend is

toward using trimix beginning at shallower depths.

c. However, air/EANx remains a viable option in the 30 metre/100 foot

to 50 metre/165 foot range in open water and reasonable conditions.

B. Advantages and disadvantages of trimix

1. Advantages

a. Reduced narcosis – Helium is not narcotic, so trimix greatly reduces

narcosis. This is particularly important for dives below 50

metres/165 feet, but is useful as shallow as 30 metres/100 feet for

complex dives, dealing with poor conditions. It is considered manda-

tory for overhead environment diving beyond 40 metres/130 feet.


A-202 padi.com


b. Reduced gas density – Helium is a lighter than oxygen and nitrogen

so it is easier to breathe under pressure. This reduction in respiratory

load is thought to help reduce carbon dioxide buildup by improving

respiratory exchange, as well by reducing the muscular effort

required to breathe.

c. Reduced oxygen exposure – At depths below 50 metres/165 feet, it

becomes increasingly important to reduce the oxygen in a breathing

gas. Helium is a better choice than nitrogen for reducing the fraction

of oxygen for both its non narcotic and its low gas density proper-

ties.

2. Disadvantages

a. Decompression times and schedules – Because helium diffuses more

rapidly than nitrogen, you need to use tables or mixed gas dive com-

puters set for the specific trimix you’re using.

• All else being equal, within typical tec diving limits, a trimix

dive requires more decompression than an air/EANx dive.

• You cannot simply use an air or EANx schedule for trimix,

even if the oxygen content is the same.

• Trimix almost always requires accelerated decompression

with higher oxygen deco gases.

• Most software and many high end tec diving computers sup-

port trimix, so planning your dives does not differ much from

what you do as a Tec 50 diver – but you must plan

for helium.

b. Theoretical DCS risk – Because helium diffuses rapidly, in theory

DCS is more likely with helium, particularly following a rapid

ascent, a poorly executed or omitted decompression stop, or similar

error.

• Recent examination of data does not find that this is clearly

the case. There may be more risk of DCS Type II (neurologi-

cal), though this isn’t clearly the case either.

• Some argue that helium’s rapid diffusion makes it more effi-

cient during decompression.


padi.com A-203


• Until we know more, the prudent practice is to assume it has

less error tolerance and higher risk; tight, well executed dive

skills and conservative schedules are part of reducing DCS

risk regardless of what gases you’re using.

• Although there is some question whether the helium diving

has a higher DCS risk, until we know more it is a risk you

must accept if you dive trimix.

c. Cost and availability – Helium is expensive, and in some areas, near-

ly impossible to get.

• Using open circuit scuba, the cost of helium can be significant.

• In some areas, helium isn’t available even at a high price.

• For this reason, in some areas trimix isn’t commonly used, or

used less frequently, for open water dives in the 30 metre/100 foot to

50 metre/165 foot range.

d. Heat loss – Helium absorbs heat rapidly and insulates poorly com-

pared to nitrogen-oxygen. For that reason (among others), you can-

not use it in a dry suit. The most common solution is to use a small

cylinder with an inflation gas (typically argon) to inflate the dry suit.

3. Note: Using trimix does not make an unsafe dive safe!

a. Trimix helps offset some of the disadvantages of air/EANx in deep

diving, but it does not eliminate risk.

b. Using trimix does not make it acceptable to dive in poor conditions

or situations beyond your experience and skill level. If the site is

unsafe for diving with air within air depth limits, pick another site

regardless of what gases you’re using.

C. Trimix and the Tec 50 certification

1. If your instructor is a DSAT Tec Trimix instructor, you may have the option

of using trimix on Tec 50 Training Dive Four.

2. Realize that this does not certify you or qualify you to dive trimix indepen-

dently.

3. To dive trimix, continue your training with the Tec Trimix 65 course and/or

the Tec Trimix Diver course.


A-204 padi.com



1. Trimix is a blend of oxygen, helium and nitrogen.

q True

q False

2. Advantages of diving with trimix include (choose all that apply):

q a. reduced narcosis.

q b. that it is a better insulator in your dry suit.

q c. it has less density.

q d. reduced oxygen exposure

3. Disadvantages of diving with trimix include (choose all that apply):

q a. theoretical DCS risk.

q b. cost and availability.

q c. longer decompression times.

q d. oxygen toxicity.

How did you do?

1. True. 2. a, c, d. 3. a, b, c.


padi.com A-205


Liability Release and Assumption of Risk for Technical Diving

Please read carefully, fi ll in all blanks and initial each paragraph before signing.

I, _________________________________________, HEREBY DECLARE THAT I AM A CERTIFIED (Participant)

SCUBA DIVER, TRAINED IN SAFE DIVING PRACTICES INCLUDING THE USE OF NITROX, AND/OR TRIMIX AND AM AWARE OF THE INHERENT HAZARDS OF SCUBA DIVING.

_____ I further state that I am an experienced diver and have been certifi ed by the following training organization(s): ____________________________ and that I am aware of the required certifi cation or equivalent experience required to participate in technical diving activities. I have been a certifi ed diver since __________, and have been diving for ________ years, with a total of approximately ________ dives, to a maximum depth of _________ metres/feet (circle one).

_____ I further declare that I am thoroughly aware of the inherent hazards of participating in technical and recreational scuba diving activities, and in consideration of being allowed to participate in this activity, I hereby assume all risks in connection with said activity, for any harm, injury or damage that I may suffer while I am participating in this activity, including all risks connected therewith, whether foreseen or unfore-seen.

_____ I further declare that I am properly trained, thoroughly informed, and completely understand the inherent hazards of Technical Scuba Diving activities, including the risk of serious injury or death. Further, I understand that diving with compressed air, oxygen-enriched air (nitrox), trimix, and 100 percent oxygen involves certain inherent risks that include but are not limited to: decompression sickness, embolism, oxygen toxicity, inert gas narcosis, marine life injuries, fi re and/or explosion hazards, and barotrauma or hyperbaric injuries which can occur and require treatment in a recompression chamber. I further understand that Tech-nical Scuba Diving activities may be conducted at a site that is remote, either by time or distance or both, from such a recompression chamber. I still choose to participate in such Technical Scuba Diving activities, despite the possible absence of a recompression chamber in proximity to the dive site.

_____ I further declare that I understand Technical Diving involves risks that exceed those encountered in recreational scuba diving. These risks may include but are not limited to: depths that exceed the limits of recreational diving; decompression procedures; over-head environments and/or the risk of entanglement that may prevent direct ascent to the surface in the event of an emergency; sudden loss of visibility; the necessity for computing both nitrogen and or helium and oxygen loading to plan dives; and the need for specialized training, equipment, and planning for different types of Technical Scuba Diving. I understand that Techni-cal Scuba Diving may involve a greater risk of serious injury or death than recreational scuba diving, and I assume the risks of this activity.

Product No. 10266 Version 1.04 (08/09) ©PADI 2009

padi.com


A-206 padi.com


_____ I understand that I AM SOLELY RESPONSIBLE FOR ENSURING MY OWN SAFETY DURING PARTICIPATION IN THIS ACTIVITY and agree that neither: 1) the facility(ies), organization(s) or supervisory personnel offering this activity, ___________________, nor their employees; 2) nor the organizers or promoters of this event; 3)nor Diving Science and Technology Corp. (DSAT); Nor 4) PADI Americas, Inc. (PADI), nor affi liate or subsidiary corporations, nor any of their respective employees, offi cers, agents or assigns (hereinafter referred to as “Released Parties”), may be held liable or responsible in any way for any injury, death or other damages to me or my family, estate, heirs, or assigns, that may occur as a result of my participation in this activity, or as a result of the negligence of any party, including the Released Parties, whether passive or active.

_____ I declare that I am in good mental and physical fi tness for diving, that I am not under the infl uence of alco-hol, nor am I under the infl uence of any drugs that are contraindicated to diving. If I am taking any medication, I declare that I have seen a physician and have approval to dive under the conditions of this activity while under the infl uence of the medication/drugs.

_____ I understand that all types of scuba diving, including Technical Diving, are physically strenuous activities and that I will be exerting myself during this activity; and if I am injured as a result of heart attack, panic, hyperven-tilation, etc. that I assume the risk of said injuries and that I will not hold the Released Parties responsible for the same.

_____ I will inspect all of my equipment prior to every use during this activity, ensuring that I have all necessary equipment, and that it is functioning properly. I will not hold the Released Parties responsible for my failure to inspect my equipment prior to diving.

____I further state that I am of lawful age and legally competent to sign this Assumption ofRisk and Liability Release Agreement, or that I have acquired the written consent of myparent or guardian. _____I understand that the terms herein are contractual and not a mere recital and that I havesigned this Release of my own free act and with the knowledge that I hereby agree towaive my legal rights. I further agree that if any provision of this Agreement is found tobe unenforceable or invalid, that provision shall be severed from this Agreement. Theremainder of this Agreement will then be construed as though the unenforceable provisionhad never been contained herein. _____I understand and agree that I am not only giving up my right to sue the Released Partiesbut also any rights my heirs, assigns, or benefi ciaries may have to sue the ReleasedParties resulting from my death. I further represent I have the authority to do so and thatmy heirs, assigns, or benefi ciaries will be estopped from claiming otherwise because ofmy representations to the Released Parties. I (participant name), __________________________________________, BY THISINSTRUMENT DO EXEMPT AND RELEASE THE FACILITY(IES), ORGANIZATION(S), OR SUPERVISORY PERSONNEL DIVE PROFESSIONALS CONDUCTING THIS ACTIVITY, AND THEIR EMPLOYEES, THE ORGANIZERS AND PROMOT-ERS OF THIS EVENT, DIVING SCIENCE AND TECHNOLOGY, CORP, PADI AMERICAS, INC., AND ALL RELATED ENTI-TIES AND RELEASED PARTIES AS DEFINED ABOVE, FROM ALL LIABILITY OR RESPONSIBILITY WHATSOEVER FORPERSONAL INJURY, PROPERTY DAMAGE OR WRONGFUL DEATH, HOWEVER CAUSED, INCLUDING BUT NOT LIM-ITED TO THE NEGLIGENCE OF THE RELEASED PARTIES, WHETHER PASSIVE OR ACTIVE. I HAVE FULLY INFORMED MYSELF OF THE CONTENTS OF THIS LIABILITY RELEASE AND ASSUMPTION OF RISK AGREEMENT BY READING IT BEFORE SIGNING IT ON BEHALF OF MYSELF AND MY HEIRS. __________________ _______________________________________________________ (Date) (Signature of Participant) __________________ _______________________________________________________ (Date) (Signature of Parent or Guardian if applicable) __________________ _______________________________________________________ (Date) (Witness)

padi.com


padi.com A-207


Liability Release and Express Assumption of Risk for Discover Tec Diving

Please read carefully, fill in all blanks and initial each paragraph before signing.

I, ______________________________, HEREBY DECLARE THAT I AM A ______________________________ (Participant)CERTIFIED SCUBA DIVER, TRAINED IN SAFE DIVING PRACTICES AND AM AWARE OF THE INHERERNT HAZARDS OF SCUBA DIVING.

______ I further declare that I have been advised and thoroughly informed of the hazards of participating in technical and recreational scuba diving activities, and in consideration of being allowed to participate in this activity, I hereby assume all risks in connection with said activity, for any harm, injury or damage that I may suffer while I am participating in this activity, including all risks connected therewith, whether foreseen or unforeseen.

______ I further declare that I am thoroughly informed, and completely understand the inherent hazards of simu-lated Technical Scuba Diving activities, including the risk of serious injury or death. Further, I understand that diving with compressed air or oxygen-enriched air (nitrox0 involves certain inherent risks that include but are not limited to: decompression sickness, embolism, oxygen toxicity, inert gas narcosis, marine life injuries, fire and/or explosion haz-ards, and barotraumas or hyperbaric injuries that can occur and require treatment in a recompression chamber. I further understand that Technical Scuba Diving activities may be conducted at a remote, either by time or distance or both, from such a recompression chamber. I still choose to participate in such simulated Technical Diving activities, despite the possible absence of a recompression chamber in proximity to the dive site.

______ I further declare that I understand simulated Technical Diving involves risk that exceeds those encountered in recreational scuba diving. These risks may include but are not limited to: the burden of additional or redundant equip-ment, including additional tanks; the necessity for computing both nitrogen and oxygen loading to plan dives; and the need for specialized training, equipment, and planning for different types of Technical Diving. I understand that simu-lated Technical Diving may involve a greater risk or serious injury or death than recreational scuba diving, and I volun-tarily assume the risk of this activity.

______ I understand that I AM SOLELY RESPONSIBLE FOR ENSURING MY OWN SAFETY DURING PARTICIPATION IN THIS ACTIVITY and agree that: 1) the facility(ies), organization(s) or supervisory personnel offering this activity, ___________, or their employees; 2) the organizers or promoters of this event; 3) Diving Science and Technology Corp. (DST); and 4) PADI Americas (PADI), its affiliate or subsidiary corporation, and of their respective employees officers, agents or assigns and all related entities (1 through 4 hereinafter referred to as “Released Parties”), may not be held liable or responsible in any way for any injury, death or other damages to me or my family, heirs, or assigns, that may occur as a result of my participation in this activity, or as a result of the negligence of any party, including the Released Parties, whether passive or active.

_____ I declare that I am in good mental and physical fitness for diving, and that I am not under the influence of alcohol, nor am I under the influence of any drugs that are contraindicated to diving. If I am taking any medication, I declare that I have seen a physician and have approval to dive under the conditions of this activity while under the influence of the medication/drugs.

______ I understand that all types of scuba diving, including simulated Technical Diving, are physically strenuous activi-ties and that I will be exerting myself during this activity; and if I am injured as a result of heart attack, panic, hyperventi-

PRODUCT NO. 10076 (Rev. 8/09) Version 1.01 – OVER – © PADI 2009


A-208 padi.com


lation, etc. that I assume the risk of said injuries and that I will not hold the Released Parties responsible for the same.

______ I will inspect all of my equipment prior to every use during this activity, ensuring that I have all necessary equip-ment, and that it is functioning properly. I will not hold the Released Parties responsible for my failure to inspect my equipment prior to diving.

______ I further state that I am of lawful age and legally competent to sign this Assumption of Risk and Liability Release Agreement, or that I have acquired the written consent of my parent or guardian.

______ I understand that the terms herein are contractual and not a mere recital and that I have signed this Release of my own free act and with the knowledge that I hereby agree to waive my legal rights. I further agree that if any provi-sion of this Agreement is found to be unenforceable or invalid, that provision shall be severed from this Agreement. The remainder of this Agreement will then be construed as though the unenforceable provision had never been con-tained herein.

______ I understand and agree that I am not only giving up my right to sue the Released Parties but also any rights my heirs, assigns, or beneficiaries may have to sue the Released Parties resulting from my death. I further represent I have the authority to do so and that my heirs, assigns, or beneficiaries will be estopped from claiming otherwise because of my representations to the Released Parties.

I, _________________________________, BY THIS INSTRUMENT DO EXEMPT _______________________ Participant Name Dive Operation/ InstructorAND RELEASE THE FACILITY(IES), ORGANIZATION(S), OR SUPERVISORY PERSONNEL, DIVE PROFESSIONALS CONDUCTING THIS ACTIVITY, AND THEIR EMPLOYEES, THE ORGANIZERS AND PROMOTERS OF THIS EVENT, DIVING SCIENCE AND TECHNOLOGY, CORP, PADI AMERICAS, INC., AND ALL RELEATED ENTITIES AND RELEASED PARTIES AS DEFINED ABOVE, FROM ALL LIABILITY OR RESPONSIBILITY WHATSOEVER FOR PERSONAL INJURY, PROPERTY DAMAGE OR WRONGFUL DEATH, HOWEVER CAUSED, INCLUDING BUT NOT LIMITED TO THE NEGLIGENCE OF THE RELEASED PARTIES, WHETHER PASSIVE OR ACTIVE. I HAVE FULLY INFORMED MYSELF OF THE CONTENTS OF THIS LIABILITY RELEASE AND ASSUMPTION OR RISK AGREEMENT BY READING IT BEFORE SIGNING IT ON BEHALF OF MYSELF AND MY HEIRS.

______ _________________________________________________________(Date) (Signature of Participant)

______ _________________________________________________________(Date) (Signature of Parent or Guardian if applicable)

______ _________________________________________________________(Date) (Witness)


padi.com A-209


Requirements: To apply for the DSAT Tec Deep Instructor rating you must meet the following requirements. Refer to the DSAT Tec Deep Diver Instructor Guide for specifics on qualifying certifications. Direct Questions to the PADI Training and Quality Management Department.

□ PADI Master Scuba Diver Trainer (or higher) Rating □ PADI Enriched Air Instructor

□ PADI Deep Diver Specialty Instructor □ DSAT Tec 50 (Tec Deep Diver) (or qualifying certification*)

* If submitting qualifying certification from another training organization, please be sure to attach photocopies of the certification.

Product No. 10172 (Rev. 7/09) Version 1.05 © PADI 2009

Tape / Attach a4.5 cm x 5.7 cm

13⁄4" x 21⁄4" (approx.)

Head and Shoulder Photo

PRINT NAME ONBACK OF PHOTO

Coin Machine Photos OK

No Dark Glasses

TEC DEEP INSTRUCTOR APPLICATION

PLEASE PRINT CLEARLY Check here if this is a change of address and you want our records changed accordingly.

Name ________________________________________________________________________________________ PADI No. _________________ First Initial Last

Mailing Address __________________________________________________________________________________________________________

City ________________________________________________________________ State/Province ______________________________________

Country ___________________________________________________________________________ Zip/Postal Code ______________________

Home Phone (_____)______________________________________ Business Phone (_____)__________________________________________

FAX (_____)_____________________________________________ Email _________________________________________________________

Date of Birth ______________________ Sex: M F Occupation ____________________________________________________ D/M/Y

CHECKLIST Application completed in full Requirements completed Successfully completed Tec Deep

Standards and Theory/Practical Exams Verification of logged dives Verification of course assistance Completion of Peer Review Waterskills Applicant and verifying instructor

signatures One photo attached See price list for fee

PLEASE DO NOT WRITE IN THIS SPACE

Date ____________________________

Amount _________________________

PAYMENT METHODSee current price list for payment information.� MasterCard � VISA � American Express� Discover Card � JCB � Maestro/Solo (UK only)� Check/Bank Draft No.* ______________________________

*Check/Bank Draft must be payable in the currency of the PADI Office the application is submitted to.

Card Number _________ __________ __________ __________

Card expiration date ____________________________________

Maestro/Solo valid from date ______ or Issue No. _____(UK only)

Cardholder Name ______________________________________ Please Print

Authorized Signature ___________________________________

Rec’d _________________________ Entr’d _________________________ Shp’d ________________________

MAIL TO – Your PADI Office

Attn. DSAT Instructor Trainer Certification

For mailing information, see current price list or visit padi.com.


A-210 padi.com


Instructor/Applicant AcknowledgementI certify that the information contained here is true and correct to the best of my knowledge and understand that this certification is subject to approval by PADI.

Applicant Signature______________________________________________________________________________ Date___________________ Signature D/M/Y

Instructor Signatures: The verifying Instructors must be a DSAT Tec Deep Instructor or a PADI Instructor with a qualifying rating.

Logged Dive Verification: I have verified that the applicant has logged at least 270 dives with at least 25 staged decompression dives with a maximum depth deeper than 40 metres/130 feet.

Verifying Instructor ____________________________________________________ PADI No. _______________ Date ___________________ Signature D/M/Y

Course Assistance Verification: I have verified that the applicant has assisted with at least two DSAT Tec 50 (Tec Deep) Diver courses (or qualifying course*) or one DSAT Tec 45 (Tec Diver Level One) Divercourse and one DSAT Tec 50 (Tec Deep) Diver course(or qualifying course*).

Course 1 Verifying Instructor ____________________________________________ PADI No. _______________ Course Date _____________ Signature D/M/Y

Course 2 Verifying Instructor ____________________________________________ PADI No. _______________ Course Date _____________ Signature D/M/Y

Tec Deep Instructor Exams: I have verified that the applicant has successfully completed the Tec Deep Instructor Standards Exam and Tec Deep Instructor Theory and Practical Application Exam.

Signature ___________________________________________________________ PADI No. _______________ Date ___________________ Verifying DSAT Tec Deep IT/Examiner D/M/Y

* When meeting this requirement by qualifying certification, enclose a copy of your technical instructor certification and proof of qualifying course assistance; contact your local PADI Office for details and any additional required documents.

Peer Review Waterskills D/M/Y1. Deploys and decompresses with lift bag and reel; maintains stop depth with little

or no depth variation while neutrally buoyant. ________/________/________

2. Performs gas switch while remaining neutrally buoyant and maintains stop depth. ________/________/________

3. Performs neutrally buoyant gas shutdown drill without significantly varying stop depth. ________/________/________

4. Maintains buoyancy control while staging and retrieving/donning stage/deco bottles. ________/________/________

5. Performs gas sharing with long hose both as a donor and a receiver. ________/________/________

6. Performs gas shutdown drill on bottom within 45 seconds. ________/________/________

7. Dives in standardized technical rig as defined in DSAT Tec Deep Diver materials. ________/________/________

I have verified that the applicant has met the peer review waterskills requirements as outlined above.

Verifying Instructor ___________________________________________________ PADI No. _______________ Date ___________________ Signature D/M/Y

DSAT Tec Deep Instructor Training Course Attendance – To be completed by the certifying DSAT Instructor Trainer only.

Course Location _______________________________________________________________________ Course Date __________________ D/M/Y

Tec Deep Instructor Trainer Name _________________________________________________________ PADI No. _____________________ Please Print Name

Tec Deep Instructor Trainer Signature ______________________________________________________ Date _________________________ Signature D/M/Y

PADI Dive Center/Resort Name ___________________________________________________________ PADI No. _____________________


padi.com A-211


MEDICAL STATEMENTParticipant Record (Confidential Information)

This is a statement in which you are informed of some potential risksinvolved in scuba diving and of the conduct required of you during thescuba training program. Your signature on this statement is required foryou to participate in the scuba training program offered

by_____________________________________________________andInstructor

_______________________________________________located in theFacility

city of_______________________, state/province of _______________.

Read this statement prior to signing it. You must complete thisMedical Statement, which includes the medical questionnaire section, toenroll in the scuba training program. If you are a minor, you must havethis Statement signed by a parent or guardian.

Diving is an exciting and demanding activity. When performedcorrectly, applying correct techniques, it is relatively safe. When

established safety procedures are not followed, however, there areincreased risks.

To scuba dive safely, you should not be extremely overweight orout of condition. Diving can be strenuous under certain conditions. Yourrespiratory and circulatory systems must be in good health. All body airspaces must be normal and healthy. A person with coronary disease, acurrent cold or congestion, epilepsy, a severe medical problem or who isunder the influence of alcohol or drugs should not dive. If you haveasthma, heart disease, other chronic medical conditions or you are tak-ing medications on a regular basis, you should consult your doctor andthe instructor before participating in this program, and on a regular basisthereafter upon completion. You will also learn from the instructor theimportant safety rules regarding breathing and equalization while scubadiving. Improper use of scuba equipment can result in serious injury. Youmust be thoroughly instructed in its use under direct supervision of aqualified instructor to use it safely.

If you have any additional questions regarding this MedicalStatement or the Medical Questionnaire section, review them with yourinstructor before signing.

Please read carefully before signing.

The purpose of this Medical Questionnaire is to find out if you should be exam-ined by your doctor before participating in recreational diver training. A positiveresponse to a question does not necessarily disqualify you from diving. A positiveresponse means that there is a preexisting condition that may affect your safetywhile diving and you must seek the advice of your physician prior to engaging indive activities.

Please answer the following questions on your past or present medical historywith a YES or NO. If you are not sure, answer YES. If any of these items apply toyou, we must request that you consult with a physician prior to participating inscuba diving. Your instructor will supply you with an RSTC Medical Statement andGuidelines for Recreational Scuba Diver’s Physical Examination to take to yourphysician.

_____ Could you be pregnant, or are you attempting to become pregnant?

_____ Are you presently taking prescription medications? (with the exception ofbirth control or anti-malarial)

_____ Are you over 45 years of age and can answer YES to one or more of thefollowing?• currently smoke a pipe, cigars or cigarettes• have a high cholesterol level• have a family history of heart attack or stroke• are currently receiving medical care• high blood pressure• diabetes mellitus, even if controlled by diet alone

Have you ever had or do you currently have…_____ Asthma, or wheezing with breathing, or wheezing with exercise?_____ Frequent or severe attacks of hayfever or allergy?_____ Frequent colds, sinusitis or bronchitis?_____ Any form of lung disease?_____ Pneumothorax (collapsed lung)?_____ Other chest disease or chest surgery?_____ Behavioral health, mental or psychological problems (Panic attack, fear of

closed or open spaces)?_____ Epilepsy, seizures, convulsions or take medications to prevent them?_____ Recurring complicated migraine headaches or take medications to pre-

vent them?_____ Blackouts or fainting (full/partial loss of consciousness)?_____ Frequent or severe suffering from motion sickness (seasick, carsick,

etc.)?

_____ Dysentery or dehydration requiring medical intervention?

_____ Any dive accidents or decompression sickness?

_____ Inability to perform moderate exercise (example: walk 1.6 km/one milewithin 12 mins.)?

_____ Head injury with loss of consciousness in the past five years?

_____ Recurrent back problems?

_____ Back or spinal surgery?

_____ Diabetes?

_____ Back, arm or leg problems following surgery, injury or fracture?

_____ High blood pressure or take medicine to control blood pressure?

_____ Heart disease?

_____ Heart attack?

_____ Angina, heart surgery or blood vessel surgery?

_____ Sinus surgery?

_____ Ear disease or surgery, hearing loss or problems with balance?

_____ Recurrent ear problems?

_____ Bleeding or other blood disorders?

_____ Hernia?

_____ Ulcers or ulcer surgery ?

_____ A colostomy or ileostomy?

_____ Recreational drug use or treatment for, or alcoholism in the past fiveyears?

Divers Medical QuestionnaireTo the Participant:

The information I have provided about my medical history is accurate to the best of my knowledge. I agree to accept responsibility for omissions regarding my failure to disclose any existing or past health condition.

_______________________________________ _________________ _______________________________________ _________________Signature Date Signature of Parent or Guardian Date

PRODUCT NO. 10063 (Rev. 06/07) Ver. 2.01 © PADI 1989, 1990, 1998, 2001, 2007© Recreational Scuba Training Council, Inc. 1989, 1990, 1998, 2001, 2007Page 1 of 6


A-212 padi.com


STUDENT

Please print legibly.

Name__________________________________________________________________________ Birth Date ________________ Age ________First Initial Last Day/Month/Year

Mailing Address __________________________________________________________________________________________________________

City________________________________________________________________ State/Province/Region ________________________________

Country ____________________________________________________________ Zip/Postal Code _____________________________________

Home Phone ( )________________________________________ Business Phone ( )______________________________________

Email _____________________________________________________ FAX_______________________________________________________

Name and address of your family physician

Physician __________________________________________________ Clinic/Hospital ______________________________________________

Address________________________________________________________________________________________________________________

Date of last physical examination ________________

Name of examiner____________________________________________ Clinic/Hospital_______________________________________________

Address ________________________________________________________________________________________________________________

Phone ( )___________________________________ Email ________________________________________________________________

Were you ever required to have a physical for diving? Yes No If so, when?________________________________________________

PHYSICIAN

This person applying for training or is presently certified to engage in scuba (self-contained underwater breathing apparatus) diving. Your opinion ofthe applicant’s medical fitness for scuba diving is requested. There are guidelines attached for your information and reference.

Physician’s Impression

I find no medical conditions that I consider incompatible with diving.

I am unable to recommend this individual for diving.

Remarks ___________________________________________________________________________________________________

___________________________________________________________________________________________________________

___________________________________________________________________________________________________________

__________________________________________________________________________ Date ___________________________Physician’s Signature or Legal Representative of Medical Practitioner Day/Month/Year

Physician_____________________________________________ Clinic/Hospital_________________________________________

Address____________________________________________________________________________________________________

Phone ( )___________________________________ Email ________________________________________________________________

Page 2 of 6


padi.com A-213


Recreational SCUBA (Self-Contained Underwater BreathingApparatus) can provide recreational divers with an enjoyablesport safer than many other activities. The risk of diving isincreased by certain physical conditions, which the relationship todiving may not be readily obvious. Thus, it is important to screendivers for such conditions.

The RECREATIONAL SCUBA DIVER’S PHYSICAL EXAMINA-TION focuses on conditions that may put a diver at increased riskfor decompression sickness, pulmonary overinflation syndromewith subsequent arterial gas embolization and other conditionssuch as loss of consciousness, which could lead to drowning.Additionally, the diver must be able to withstand some degree ofcold stress, the physiological effects of immersion and the opticaleffects of water and have sufficient physical and mental reservesto deal with possible emergencies.

The history, review of systems and physical examination shouldinclude as a minimum the points listed below. The list of condi-tions that might adversely affect the diver is not all-inclusive, butcontains the most commonly encountered medical problems. Thebrief introductions should serve as an alert to the nature of therisk posed by each medical problem.

The potential diver and his or her physician must weigh thepleasures to be had by diving against an increased risk of deathor injury due to the individual’s medical condition. As with anyrecreational activity, there are no data for diving enabling the cal-culation of an accurate mathematical probability of injury. Experi-ence and physiological principles only permit a qualitativeassessment of relative risk.

For the purposes of this document, Severe Risk implies that anindividual is believed to be at substantially elevated risk of decom-pression sickness, pulmonary or otic barotrauma or altered con-sciousness with subsequent drowning, compared with the gener-al population. The consultants involved in drafting this documentwould generally discourage a student with such medical prob-lems from diving. Relative Risk refers to a moderate increase inrisk, which in some instances may be acceptable. To make adecision as to whether diving is contraindicated for this categoryof medical problems, physicians must base their judgement onan assessment of the individual patient. Some medical problemswhich may preclude diving are temporary in nature or respon-sive to treatment, allowing the student to dive safely after theyhave resolved.

Diagnostic studies and specialty consultations should be obtainedas indicated to determine the diver’s status. A list of references isincluded to aid in clarifying issues that arise. Physicians andother medical professionals of the Divers Alert Network (DAN)associated with Duke University Health System are available forconsultation by phone +1 919 684 2948 during normal businesshours. For emergency calls, 24 hours 7 days a week, call +1 919684 8111 or +1 919 684 4DAN (collect). Related organizationsexist in other parts of the world – DAN Europe in Italy +39 039605 7858, DAN S.E.A.P. in Australia +61 3 9886 9166 and DiversEmergency Service (DES) in Australia +61 8 8212 9242, DANJapan +81 33590 6501 and DAN Southern Africa +27 11 2420380. There are also a number of informative websites off e r i n gsimilar advice.

NEUROLOGICALNeurological abnormalities affecting a diver’s ability to performexercise should be assessed according to the degree of compro-mise. Some diving physicians feel that conditions in which therecan be a waxing and waning of neurological symptoms andsigns, such as migraine or demyelinating disease, contraindicatediving because an exacerbation or attack of the preexisting dis-ease (e.g.: a migraine with aura) may be difficult to distinguish

from neurological decompression sickness. A history of headinjury resulting in unconsciousness should be evaluated for riskof seizure.

Relative Risk Conditions• Complicated Migraine Headaches whose symptoms or

severity impair motor or cognitive function, neurologicmanifestations

• History of Head Injury with sequelae other than seizure

• Herniated Nucleus Pulposus

• Intracranial Tumor or Aneurysm

• Peripheral Neuropathy

• Multiple Sclerosis

• Trigeminal Neuralgia

• History of spinal cord or brain injury

Temporary Risk ConditionHistory of cerebral gas embolism without residual where pul-

monary air trapping has been excluded and for which there

is a satisfactory explanation and some reason to believe that

the probability of recurrence is low.

Severe Risk ConditionsAny abnormalities where there is a significant probability ofunconsciousness, hence putting the diver at increased risk ofdrowning. Divers with spinal cord or brain abnormalities whereperfusion is impaired may be at increased risk of decompressionsickness.

Some conditions are as follows:

• History of seizures other than childhood febrile seizures

• History of Transient Ischemic Attack (TIA) or Cerebrovas-cular Accident (CVA)

• History of Serious (Central Nervous System, Cerebral orInner Ear) Decompression Sickness with residual deficits

CARDIOVASCULAR SYSTEMSRelative Risk Conditions The diagnoses listed below potentially render the diver unable tomeet the exertional performance requirements likely to beencountered in recreational diving. These conditions may leadthe diver to experience cardiac ischemia and its consequences.Formalized stress testing is encouraged if there is any doubtregarding physical performance capability. The suggested mini-mum criteria for stress testing in such cases is at least 13METS.* Failure to meet the exercise criteria would be of signifi-cant concern. Conditioning and retesting may make later qualifi-cation possible. Immersion in water causes a redistribution ofblood from the periphery into the central compartment, an effectthat is greatest in cold water. The marked increase in cardiacpreload during immersion can precipitate pulmonary edema inpatients with impaired left ventricular function or significant valvu-lar disease. The effects of immersion can mostly be gauged byan assessment of the diver’s performance while swimming on thesurface. A large proportion of scuba diving deaths in North Amer-ica are due to coronary artery disease. Before being approved toscuba dive, individuals older than 40 years are recommended toundergo risk assessment for coronary artery disease. Formalexercise testing may be needed to assess the risk.

* METS is a term used to describe the metabolic cost. The MET at restis one, two METS is two times the resting level, three METS is threetimes the resting level, and so on. The resting energy cost (net oxygenrequirement) is thus standardized. (Exercise Physiology; Clark, PrenticeHall, 1975.)

Guidelines for Recreational Scuba Diver’s Physical ExaminationInstructions to the Physician:

Page 3 of 6


A-214 padi.com


Relative Risk Conditions• History of Coronary Artery Bypass Grafting (CABG)

• Percutaneous Balloon Angioplasty (PCTA) or CoronaryArtery Disease (CAD)

• History of Myocardial Infarction

• Congestive Heart Failure

• Hypertension

• History of dysrythmias requiring medication for suppres-sion

• Valvular Regurgitation

PacemakersThe pathologic process that necessitated should beaddressed regarding the diver’s fitness to dive. In thoseinstances where the problem necessitating pacing does notpreclude diving, will the diver be able to meet the perform-ance criteria?

* NOTE: Pacemakers must be certified by the manufacturer as ableto withstand the pressure changes involved in recreational diving.

Severe RisksVenous emboli, commonly produced during decompression,

may cross major intracardiac right-to-left shunts and enter

the cerebral or spinal cord circulations causing neurological

decompression illness. Hypertrophic cardiomyopathy and

valvular stenosis may lead to the sudden onset of uncon-

sciousness during exercise.

PULMONARYAny process or lesion that impedes airflow from the lungs placesthe diver at risk for pulmonary overinflation with alveolar ruptureand the possibility of cerebral air embolization. Many interstitialdiseases predispose to spontaneous pneumothorax: Asthma(reactive airway disease), Chronic Obstructive Pulmonary Dis-ease (COPD), cystic or cavitating lung diseases may all cause airtrapping. The 1996 Undersea and Hyperbaric Medical Society(UHMS) consensus on diving and asthma indicates that for therisk of pulmonary barotrauma and decompression illness to beacceptably low, the asthmatic diver should be asymptomatic andhave normal spirometry before and after an exercise test.Inhalation challenge tests (e.g.: using histamine, hypertonicsaline or methacholine) are not sufficiently standardized to beinterpreted in the context of scuba diving.

A pneumothorax that occurs or reoccurs while diving may be cat-astrophic. As the diver ascends, air trapped in the cavityexpands and could produce a tension pneumothorax.

In addition to the risk of pulmonary barotrauma, respiratory dis-ease due to either structural disorders of the lung or chest wall orneuromuscular disease may impair exercise performance. Struc-tural disorders of the chest or abdominal wall (e.g.: prune belly),or neuromuscular disorders, may impair cough, which could belife threatening if water is aspirated. Respiratory limitation due todisease is compounded by the combined effects of immersion(causing a restrictive deficit) and the increase in gas density,which increases in proportion to the ambient pressure (causingincreased airway resistance). Formal exercise testing may behelpful.

Relative Risk Conditions• History of Asthma or Reactive Airway Disease (RAD)*

• History of Exercise Induced Bronchospasm (EIB)*

• History of solid, cystic or cavitating lesion*

• Pneumothorax secondary to:

-Thoracic Surgery

-Trauma or Pleural Penetration*

-Previous Overinflation Injury*

• Obesity

• History of Immersion Pulmonary Edema Restrictive Dis-ease*

• Interstitial lung disease: May increase the risk of pneu-mothorax

* Spirometry should be normal before and after exercise

Active Reactive Airway Disease, Active Asthma, Exercise

Induced Bronchospasm, Chronic Obstructive Pulmonary

Disease or history of same with abnormal PFTs or a positive

exercise challenge are concerns for diving.

Severe Risk Conditions• History of spontaneous pneumothorax. Individuals who

have experienced spontaneous pneumothorax should avoiddiving, even after a surgical procedure designed to preventrecurrence (such as pleurodesis). Surgical procedures eitherdo not correct the underlying lung abnormality (e.g.: pleurode-sis, apical pleurectomy) or may not totally correct it (e.g.: resec-tion of blebs or bullae).

• Impaired exercise performance due to respiratory disease.

GASTROINTESTINALTemporary RisksAs with other organ systems and disease states, a process whichchronically debilitates the diver may impair exercise performance.Additionally, dive activities may take place in areas remote frommedical care. The possibility of acute recurrences of disability orlethal symptoms must be considered.

Temporary Risk Conditions• Peptic Ulcer Disease associated with pyloric obstruction or

severe reflux

• Unrepaired hernias of the abdominal wall large enough tocontain bowel within the hernia sac could incarcerate.

Relative Risk Conditions• Inflammatory Bowel Disease

• Functional Bowel Disorders

Severe RisksAltered anatomical relationships secondary to surgery or malfor-mations that lead to gas trapping may cause serious problems.Gas trapped in a hollow viscous expands as the divers surfacesand can lead to rupture or, in the case of the upper GI tract, eme-sis. Emesis underwater may lead to drowning.

Severe Risk Conditions• Gastric outlet obstruction of a degree sufficient to produce

recurrent vomiting

• Chronic or recurrent small bowel obstruction

• Severe gastroesophageal reflux

• Achalasia

• Paraesophageal Hernia

ORTHOPAEDICRelative impairment of mobility, particularly in a boat or ashorewith equipment weighing up to 18 kgs/40 pounds must beassessed. Orthopaedic conditions of a degree sufficient to impairexercise performance may increase the risk.

Relative Risk Conditions• Amputation

• Scoliosis must also assess impact on respiratory functionand exercise performance.

• Aseptic Necrosis possible risk of progression due toeffects of decompression (evaluate the underlying medical

Page 4 of 6


padi.com A-215


cause of decompression may accelerate/escalate the pro-gression).

Temporary Risk Conditions• Back pain

HEMATOLOGICALAbnormalities resulting in altered rheological properties may the-oretically increase the risk of decompression sickness. Bleedingdisorders could worsen the effects of otic or sinus barotrauma,and exacerbate the injury associated with inner ear or spinal corddecompression sickness. Spontaneous bleeding into the joints(e.g.: in hemophilia) may be difficult to distinguish from decom-pression illness.

Relative Risk Conditions• Sickle Cell Disease

• Polycythemia Vera

• Leukemia

• Hemophilia/Impaired Coagulation

METABOLIC AND ENDOCRINOLOGICALWith the exception of diabetes mellitus, states of altered hormon-al or metabolic function should be assessed according to theirimpact on the individual’s ability to tolerate the moderate exerciserequirement and environmental stress of sport diving. Obesitymay predispose the individual to decompression sickness, canimpair exercise tolerance and is a risk factor for coronary arterydisease.

Relative Risk Conditions• Hormonal Excess or Deficiency

• Obesity

• Renal Insufficiency

Severe Risk ConditionsThe potentially rapid change in level of consciousness asso-

ciated with hypoglycemia in diabetics on insulin therapy or

certain oral hypoglycemic medications can result in drown-

ing. Diving is therefore generally contraindicated, unlessassociated with a specialized program that addresses these

issues. [See “Guidelines for Recreational Diving with Diabetes”at www/wrstc.com and www.diversalertnetwork.org.]

Pregnancy: The effect of venous emboli formed duringdecompression on the fetus has not been thoroughly inves-

tigated. Diving is therefore not recommended during any

stage of pregnancy or for women actively seeking to

become pregnant.

BEHAVIORAL HEALTHBehavioral: The diver’s mental capacity and emotional make-upare important to safe diving. The student diver must have suffi-cient learning abilities to grasp information presented to him byhis instructors, be able to safely plan and execute his own divesand react to changes around him in the underwater environment.The student’s motivation to learn and his ability to deal withpotentially dangerous situations are also crucial to safe scubadiving.

Relative Risk Conditions• Developmental delay

• History of drug or alcohol abuse

• History of previous psychotic episodes

• Use of psychotropic medications

Severe Risk Conditions• Inappropriate motivation to dive – solely to please spouse,

partner or family member, to prove oneself in the face of

personal fears

• Claustrophobia and agoraphobia

• Active psychosis

• History of untreated panic disorder

• Drug or alcohol abuse

OTOLARYNGOLOGICALEqualisation of pressure must take place during ascent anddescent between ambient water pressure and the external audi-tory canal, middle ear and paranasal sinuses. Failure of this tooccur results at least in pain and in the worst case rupture of theoccluded space with disabling and possible lethal consequences.

The inner ear is fluid filled and therefore noncompressible. Theflexible interfaces between the middle and inner ear, the roundand oval windows are, however, subject to pressure changes.Previously ruptured but healed round or oval window membranesare at increased risk of rupture due to failure to equalise pressureor due to marked overpressurisation during vigorous or explosiveValsalva manoeuvres.

The larynx and pharynx must be free of an obstruction to airflow.The laryngeal and epiglotic structure must function normally toprevent aspiration.

Mandibular and maxillary function must be capable of allowingthe patient to hold a scuba mouthpiece. Individuals who havehad mid-face fractures may be prone to barotrauma and ruptureof the air filled cavities involved.

Relative Risk Conditions• Recurrent otitis externa

• Significant obstruction of external auditory canal

• History of significant cold injury to pinna

• Eustachian tube dysfunction

• Recurrent otitis media or sinusitis

• History of TM perforation

• History of tympanoplasty

• History of mastoidectomy

• Significant conductive or sensorineural hearing impair-ment

• Facial nerve paralysis not associated with barotrauma

• Full prosthedontic devices

• History of mid-face fracture

• Unhealed oral surgery sites

• History of head and/or neck therapeutic radiation

• History of temperomandibular joint dysfunction

• History of round window rupture

Severe Risk Conditions• Monomeric TM

• Open TM perforation

• Tube myringotomy

• History of stapedectomy

• History of ossicular chain surgery

• History of inner ear surgery

• Facial nerve paralysis secondary to barotrauma

• Inner ear disease other than presbycusis

• Uncorrected upper airway obstruction

• Laryngectomy or status post partial laryngectomy

• Tracheostomy

• Uncorrected laryngocele

• History of vestibular decompression sickness

Page 5 of 6


A-216 padi.com


1. Bennett, P. & Elliott, D (eds.)(1993). The Physiology and Medicineof Diving. 4th Ed., W.B. Saunders Company Ltd., London, England.

2. Bove, A., & Davis, J. (1990). Diving Medicine. 2nd Edition, W.B.Saunders Company, Philadelphia, PA.

3. Davis, J., & Bove, A. (1986). “Medical Examination of Sport ScubaDivers, Medical Seminars, Inc.,” San Antonio, TX

4. Dembert, M. & Keith, J. (1986). “Evaluating the Potential PediatricScuba Diver.” AJDC, Vol. 140, November.

5. Edmonds, C., Lowry, C., & Pennefether, J. (1992) .3rd ed., Divingand Subaquatic Medicine. Butterworth & Heineman Ltd., Oxford,England.

6. Elliott, D. (Ed) (1994). “Medical Assessment of Fitness to Dive.”Proceedings of an International Conference at the Edinburgh Con-ference Centre, Biomedical Seminars, Surry, England.

7. “Fitness to Dive,” Proceedings of the 34th Underwater & HyperbaricMedical Society Workshop (1987) UHMS Publication Number70(WS-FD) Bethesda, MD.

Paul A. Thombs, M.D., Medical DirectorHyperbaric Medical CenterSt. Luke’s Hospital, Denver, CO, USA

Peter Bennett, Ph.D., D.Sc.Professor, AnesthesiologyDuke University Medical CenterDurham, NC, [email protected]

Richard E. Moon, M.D., F.A.C.P., F.C.C.P.Departments of Anesthesiology and PulmonaryMedicineDuke University Medical CenterDurham, NC, USA

Roy A. Myers, M.D.MIEMSBaltimore, MD, USA

William Clem, M.D., Hyperbaric ConsultantDivision Presbyterian/St. Luke’s Medical CenterDenver, CO, USA

John M. Alexander, M.D.Northridge HospitalLos Angeles, CA, USA

Des Gorman, B.Sc., M.B.Ch.B., F.A.C.O.M.,F.A.F.O.M., Ph.D.Professor of MedicineUniversity of Auckland, Auckland, [email protected]

Alf O. Brubakk, M.D., Ph.D.Norwegian University of Science and TechnologyTrondheim, [email protected]

Alessandro Marroni, M.D.Director, DAN EuropeRoseto, ItalyHugh Greer, M.D.Santa Barbara, CA, [email protected]

BIBLIOGRAPHY/REFERENCE

ENDORSERS

Page 6 of 6

8. Neuman, T. & Bove, A. (1994). “Asthma and Diving.” Ann. Allergy,Vol. 73, October, O’Conner & Kelsen.

9. Shilling, C. & Carlston, D. & Mathias, R. (eds) (1984). ThePhysician’s Guide to Diving Medicine. Plennum Press, New York,NY.

10. Undersea and Hyperbaric Medical Society (UHMS)www.UHMS.org

11. Divers Alert Network (DAN) United States, 6 West Colony Place,Durham, NC www.DiversAlertNetwork.org

12. Divers Alert Network Europe, P.O. Box 64026 Roseto, Italy, tele-phone non-emergency line: weekdays office hours +39-085-893-0333, emergency line 24 hours: +39-039-605-7858

13. Divers Alert Network S.E.A.P., P. O. Box 384, Ashburton, Aus-tralia, telephone 61-3-9886-9166

14. Divers Emergency Service, Australia, www.rah.sa.gov.au/hyper-baric, telephone 61-8-8212-9242

15. South Pacific Underwater Medicine Society (SPUMS), P.O. Box190, Red Hill South, Victoria, Australia, www.spums.org.au

16. European Underwater and Baromedical Society, www.eubs.org

Christopher J. Acott, M.B.B.S., Dip. D.H.M.,F.A.N.Z.C.A.Physician in Charge, Diving MedicineRoyal Adelaide HospitalAdelaide, SA 5000, Australia

Chris Edge, M.A., Ph.D., M.B.B.S., A.F.O.M.Nuffield Department of AnaestheticsRadcliffe InfirmaryOxford, United [email protected]

Richard Vann, Ph.D.Duke University Medical CenterDurham, NC, USA

Keith Van Meter, M.D., F.A.C.E.P.Assistant Clinical Professor of SurgeryTulane University School of MedicineNew Orleans, LA, USA

Robert W. Goldmann, M.D.St. Luke’s HospitalMilwaukee, WI, USA

Paul G. Linaweaver, M.D., F.A.C.P.Santa Barbara Medical ClinicUndersea Medical SpecialistSanta Barbara, CA, USA

James Vorosmarti, M.D.6 Orchard Way SouthRockville, MD, USA

Tom S. Neuman, M.D., F.A.C.P., F.A.C.P.M.Associate Director, Emergency Medical ServicesProfessor of Medicine and SurgeryUniversity of California at San DiegoSan Diego, CA, USA

Yoshihiro Mano, M.D.ProfessorTokyo Medical and Dental UniversityTokyo, [email protected]

Simon Mitchell, MB.ChB., DipDHM, Ph.D.Wesley Centre for Hyperbaric MedicineMedical DirectorSandford Jackson Bldg., 30 Chasely StreetAuchenflower, QLD 4066 [email protected]

Jan Risberg, M.D., Ph.D.NUI, Norway

Karen B.Van Hoesen, M.D.Associate Clinical ProfessorUCSD Diving Medicine CenterUniversity of California at San DiegoSan Diego, CA, USA

Edmond Kay, M.D., F.A.A.F.P.Dive Physician & Asst. Clinical Prof. of Family MedicineUniversity of WashingtonSeattle, WA, [email protected]

Christopher W. Dueker, TWS, M.D.Atherton, CA, [email protected]

Charles E. Lehner, Ph.D.Department of Surgical SciencesUniversity of WisconsinMadison, WI, [email protected]

Undersea & Hyperbaric Medical Society10531 Metropolitan AvenueKensington, MD 20895, USA

Diver’s Alert Network (DAN)6 West Colony PlaceDurham, NC 27705


padi.com A-217


Tec Diver Statement of Understanding and Learning AgreementThis statement informs you of hazards, risks and your responsibilities for participating in the DSAT Tec Diver course. Your signature acknowledges that you accept these risks and responsibilities.

I, ___________________________________________________, understand that as a DSAT Tec 40,45 or 50 diver I should:

1. Maintain good mental and physical health for diving.Refrain from being under the influence of alcohol ordrugs when tec diving. Stay proficient in divingskills, in particular, the skills required for certifica-tion as a DSAT Tec 40, 45 or 50 diver.

2. Engage only in diving activities consistent with mytraining and experience.

3. Use complete, well-maintained, reliable equipmentfor which I have appropriate training.

4. Adhere to the team diving concept, but always beprepared to complete any dive without the assis-tance of a team mate. Although self sufficient, theresponsible tec diver dives as part of a team andadheres to team diving principles.

5. Maintain the proper attitude during training in whichI agree to:

• Follow the instructor’s directions and dive plansstrictly, and not to separate from the instructor ormy dive team.

• Refrain from tec diving outside this course until I amfully qualified and certified.

• Accept the risk for this type of diving, and for spe-cific risks unique to each dive environment, and toimmediately notify the instructor if this riskbecomes intolerable for me.

• Recognize the desirability of carrying diver accidentinsurance that covers tec diving (if available in mylocal area), and recognize that my instructor mayrequire me to have it.

6. Demonstrate self sufficiency – plan each dive asthough it will be necessary to make the dive andhandle all emergencies alone.

7. Demonstrate discipline and an attitude consistentwith responsible technical diving – I will not cut cor-ners, bend the rules, disregard dive plans, omit safe-ty equipment or exceed the limits of my training.

8. Obtain an orientation when diving in new environ-ments.

9. Know, obey and respect local diving laws and regula-tions including private land owner relations.

10. Accept the responsibility for my personal safety,while accepting and acknowledging the risks, anddemands tec diving imposes.

11. Stay informed on and dive according to the stateof the art in diving, tec diving, dive rescue, diveequipment and other influences on my safety as atec diver.

12. Accept that technical scuba diving has many gen-eral risks and hazards that either don’t exist inrecreational diving, or aren’t as severe, including:

• No direct access to the surface in an emergencydue to decompression requirements.

• Hypoxia/hyperoxia resulting from using to thewrong gas, which can lead to drowning.

• Narcosis, which can lead to poor judgment/baddecisions that can cause an accident.

• DCS due to improper gas analysis, missed decostops, loss of deco gas and individual susceptibili-ty. DCS can cause permanent injury or death.

• Omitted procedures due to task loading, whichcan lead to accidents, DCS, air embolism, oxygentoxicity, or drowning.

• Drowning or air embolism due to BCD failure.• Extensive equipment requirements with redundant

configurations, which can lead to ergonomic com-plexity, increased risk of error and a physical bur-den.

13. I accept that a significant difference exists betweenrecreational scuba diving and technical scuba div-ing, and that in technical scuba diving, even if youdo everything right, there is still a higher inherentpotential for an accident leading to permanentinjury or death.

14. I accept that physical fitness affects my perform-ance and ability as a tec diver. Lack of the physicalfitness required can affect my safety by limiting myability to respond to an emergency, or by directlyleading to injuries. It is my responsibility to stay fitto dive, and to dive with the limits of my fitness.

I have read the above statements and have had any questions answered to my satisfaction. I understand the impor-tance and purpose of these practices and recognize they are for my own safety and well being.

I understand that failing to ahere to the above statements will put me at risk, and may be grounds for my dismissalfrom the Tec Diver course. I acknowledge that the instructor is not permitted to and will not certify me if I don’tmeet all course performance requirements or if I demonstrate an attitude or behavior incompatible with responsi-ble technical diving practices.

__________________________________________________ ___________________________Participant Signature Day/Month/Year

padi.com

Product No. 10267 Version 1.01 (08/09) © PADI 2009


A-218 padi.com


DSAT Tec 40 Answer Key Final Exam A

1. � � � �

2. � � � �3. � True � False4. � � � �

5. � True � False6. � � � �

7. � � � �

8. � True � False9. 1.4

10. 1.611. � � � �12. � True � False13. � � � �14. � � � �15. � � � �16. � � � �

17. � True � False18. � � � �19. Gas management,

Decompression,Mission, Oxygen,Inert gas narcosis,Thermal exposure,Logistics,

20. � � � �21. � � � �22. buoyancy control,

depth23. � � � �

24. � � � �25. � � � �26. � � � �27. end,

reason

Note to Instructor: The student must score 80 percent or better tobe successful, and you must review all questions answered incor-rectly until the student demonstrates mastery.

When scoring short answer and fill in the blank, allow latitude for dif-fering word choice and variation, provided that the student still

28. � True � False29. � True � False30. � � � �31. Metric: 3300 litres

Imperial: 285 cubic feet32. � � � �

33. � � � �34. chest 35. Note the actual

depth, Observe thedepth on the cylin-der, Turn open thevalve, Orient thesecond stage,eXamine team mate

36. � � � �

37. � � � �38. � � � �39. � � � �

40. � � � �41. � � � �

42. � � � �43. Metric: 15 litres per

minuteImperial: 1.1 cubic feet

per minute 44. Metric: 342 litres

Imperial: 11.02 cubic feet

45. Metric: 2425.5 litres Imperial: 88.94

cubic feet 46. Metric: 28%

Imperial: 28%

47. Metric: 5940 litres Imperial: 201.25

cubic feet 48. Metric: 2280 litres


49. Metric: 4510 litres Imperial: 230 cubic feet

50. Metric: 1.28 Imperial: 1.29

A B C D A B C DA B C D

demonstrates mastery and a complete understanding of the concept.For example, for a question like, “Consider unneeded equipment_______ in an emergency,” the Answer Key may list “disposable.”“Discardable,” “trash,” etc. would be correct answers as well.

Product No. 71042 9/09 Version 1.0 © PADI 2009


padi.com A-219


DSAT Tec 40 Answer Key Final Exam B

1. � � � �

2. � � � �3. � True � False4. � � � �

5. � True � False6. � � � �

7. � � � �

8. � True � False9. 1.4

10. 1.611. � � � �12. � True � False13. � � � �14. � � � �15. � � � �16. � � � �

17. � True � False18. � � � �19. Gas management,

Decompression,Mission, Oxygen,Inert gas narcosis,Thermal exposure,Logistics,

20. � � � �21. � � � �22. buoyancy control,

depth23. � � � �

24. � � � �25. � � � �26. � � � �27. end,

reason

28. � True � False29. � True � False30. � True � False31. Metric: 2520 litres

Imperial: 318 cubic feet32. � � � �

33. � � � �34. chest 35. Note the actual

depth, Observe thedepth on the cylin-der, Turn open thevalve, Orient thesecond stage,eXamine team mate

36. � � � �

37. � � � �38. � � � �39. � � � �

40. � � � �41. � � � �

42. � � � �43. Metric: 122.5 litres

per minute Imperial: 3.381 cubic

feet perminute

44. Metric: 2365 litres Imperial: 68.8

cubic feet 45. Metric: 34

Imperial: 34

46. Metric: 2280 litresImperial: 74.66

cubic feet47. Metric: 2400 litres




50. Metric: 20 litres perminute

Imperial: .86 cubic feetper minute







A-220 padi.com



1. � � � �

2. � � � �3. � True � False4. � � � �5. death6. � � � �7. � � � �

8. � True � False9. � � � �

10. Metric: 3000/ 36 = 83.33 barTurn Pressure = 150 – 83 = 67 barImperial: Baseline = 208/2640 = .079150÷ .079 = 1898.7Turn Pressure = 2640 – 1899 = 740

11. � � � �

12. � � � �13. � � � �14. � � � �

15. � � � �16. � True � False17. � � � �

18. � � � �19. � � � �

20. � � � �

21. Metric: 28.91Imperial: 28.88

22. � � � �23. � � � �24. � True � False25. � � � �

26. � � � �27. 52528. � � � �29. � � � �

30. � � � �31. � � � �

32. � � � �33. � True � False34. � � � �35. � � � �36. � � � �37. � True � False38. � � � �39. Gas Management

DecompressionMission ObjectiveOxygen Inert gas narcosisThermal exposureLogistics

40. � True � False41. � � � �42. � � � �

43. 125 bar/1950psi44. � True � False45. � � � �46. � � � �

47. � � � �

48. � � � �49. � True � False50. � � � �

A B C D A B C D






padi.com A-221



1. � � � �

2. � � � �3. � True � False4. � � � �5. death6. � � � �7. � � � �

8. � True � False9. � � � �

10. Metric: 3000/ 36 = 83.33 barTurn Pressure = 150 – 83 = 67 barImperial: Baseline = 208/2640 = .079150÷ .079 = 1898.7Turn Pressure = 2640 – 1899 = 740

11. � � � �

12. � � � �13. � � � �14. � � � �

15. � � � �16. � True � False17. � � � �

18. � � � �19. � � � �

20. � � � �

21. Metric: 34.48Imperial: 34.72

22. � � � �23. � � � �24. � True � False25. � � � �

26. � � � �27. 52528. � � � �29. � � � �

30. � � � �31. � � � �

32. � � � �33. � True � False34. � � � �35. � � � �36. � � � �37. � True � False38. � � � �39. Gas Management

DecompressionMission ObjectiveOxygen Inert gas narcosisThermal exposureLogistics

40. � True � False41. � � � �42. � � � �

43. 125 bar/1950psi44. � True � False45. � � � �46. � � � �

47. � � � �

48. � � � �49. � True � False50. � � � �

A B C D A B C D






A-222 padi.com



1. getting the victim tothe surface

2. � � � �3. � � � �

4. � � � �5. � True � False6. � � � �7. last 8. � � � �9. � � � �

10. oxygen11. Metric: 64 bar

Imperial: 929 psi12. � � � �13. � � � �

14. patience15. time16. � True � False17. fail18. � � � �

19. � � � �

20. � � � �

21. alone22. � True � False23. � � � �

24. Metric: Yes. (483 x 1.5 = 724.5 litres ofoxygen needed; 11 X 66= 726 litres)Imperial: Yes. (17.03 x 1.5 = 25.5 cubic feet of oxygen needed; 1000/3000 x 80 = 26.66cf)

25. Metric: Yes. (712.5 litres of oxygen needed)Imperial: Yes. (25.18 cubic feet of oxygen needed)

A B C D A B C D






padi.com A-223



1. Getting the victim tothe surface

2. � � � �3. � � � �

4. � � � �5. � True � False6. � � � �7. last 8. � � � �9. � � � �

10. oxygen11. Metric: 75 bar.

(3312/26 = 127, 202 -127 = 25)Imperial: 1030 psi. (117.8/0.63 = 1870, 2900 – 1870 = 1030)

12. � � � �13. � � � �

14. patience15. reserve16. � True � False17. hurt18. � � � �

19. � � � �

20. � � � �

21. finish22. � True � False23. � � � �

24. Metric: Yes. (483 x 1.5 = 724.5 litres ofoxygen needed; 11 X 66= 726 litres)Imperial: Yes. (18.03 x 1.5 = 27.05 cubic feetof oxygen needed; 1500/3000 x 80 = 40 cf)

25. Metric: Yes. (772.8 litres of oxygen needed)Imperial: Yes. (27.04 cubic feet of oxygen needed)

A B C D A B C D






A-224 padi.com


DSAT Tec 40 Answer Sheet Final Exam A

1. � � � �

2. � � � �3. � True � False4. � � � �5. � True � False6. � � � �7. � � � �8. � True � False9. _________________

10. _________________11. � � � �12. � True � False13. � � � �14. � � � �15. � � � �16. � � � �17. � True � False18. � � � �19. _______________________________________________________________________________________________________________________________20. � � � �21. � � � �22. _______________________________________23. � � � �24. � � � �25. � � � �26. � � � �27. _______________________________________

28. � True � False29. � True � False30. � � � �31. _______________________________________32. � � � �33. � � � �34. _________________35. ____________________________________________________________________________________________________________________________________________________36. � � � �37. � � � �38. � � � �39. � � � �40. � � � �41. � � � �42. � � � �43. ___________________________________________________________________________________44. _____________________________________________________________45. _____________________________________________________________46. _______________________________________

47. _______________________________________48. _______________________________________49. _______________________________________50. _______________________________________




padi.com A-225


DSAT Tec 40 Answer Sheet Final Exam B

1. � � � �

2. � � � �3. � True � False4. � � � �5. � True � False6. � � � �7. � � � �8. � True � False9. _________________

10. _________________11. � � � �12. � True � False13. � � � �14. � � � �15. � � � �16. � � � �17. � True � False18. � � � �19. _______________________________________________________________________________________________________________________________20. � � � �21. � � � �22. _______________________________________23. � � � �24. � � � �25. � � � �26. � � � �27. _______________________________________

28. � True � False29. � True � False30. � � � �31. _______________________________________32. � � � �33. � � � �34. _________________35. ____________________________________________________________________________________________________________________________________________________36. � � � �37. � � � �38. � � � �39. � � � �40. � � � �41. � � � �42. � � � �43. _______________________________________________________________________________________________________________________________44. _____________________________________________________________45. _____________________________________________________________

46. _______________________________________47. _______________________________________48. _______________________________________49. _______________________________________50. _______________________________________




A-226 padi.com


DSAT Tec 45 Answer Sheet Final Exam A

1. � � � �

2. � � � �3. � True � False4. � � � �5. _________________6. � � � �7. � � � �8. � True � False9. � � � �

10. _______________________________________11. � � � �12. � � � �13. � � � �14. � � � �15. � � � �16. � True � False17. � � � �

18. � � � �19. � � � �20. � � � �

21. _______________________________________22. � � � �23. � � � �24. � True � False25. � � � �26. � � � �27. _________________28. � � � �29. � � � �30. � � � �31. � � � �32. � � � �

33. � True � False34. � � � �35. � � � �36. � � � �37. � True � False38. � � � �39. ____________________________________________________________________________________________________________________________________________________40. � True � False41. � � � �42. � � � �43. _________________44. � True � False45. � � � �46. � � � �47. � � � �48. � � � �49. � True � False50. � � � �

A B C D A B C D



padi.com A-227




A-228 padi.com




padi.com A-229




InstructorGuide


70911 79606 tec-appendix

Sports

open waterdepths

limited open water

metres30 feetdecompression

metres30 feetmaximum

decompression dive

tec diving

metres60 feetdecompression

metres60 feetmaximum