revised: september 2009 copyright ©1997-2009—all rights reserved north slope training cooperative...

Revised: September 2009 Copyright ©1997-2009—All Rights Reserved

North Slope Training Cooperative

1

Confined Space EntryCourse No. NSTC-17

Revised: September 2009 — Course No. NSTC-17 North Slope Training CooperativeCopyright ©1997-2009—All Rights Reserved 2

Introductions

• Name

• Company

• Position

• Length of time in Alaska

• Experience on North Slope or other industrial sites

Revised: September 2009 — Course No. NSTC-17 North Slope Training CooperativeCopyright ©1997-2009—All Rights Reserved

Administration and Safety

• Emergency Procedures

• Breaks, Lunch

• Restrooms, Smoking

• Safety Minute

3

Revised: September 2009 — Course No. NSTC-17 Copyright ©1997-2009—All Rights Reserved


4

Course Overview


Why Is This Class Important?

• FACT: Most workers die in confined spaces simply because they do not recognize the hazards.

• FACT: Most deaths in confined spaces occur because of atmospheric deficiencies.

• FACT: 60% of confined space fatalities are rescue attempts.


Goal

To ensure that employees can safely enter and work in confined spaces.

ASH page 84


Objectives

Upon completion of this course, employees will be able to:

• Describe the characteristics of a confined space

• Explain the importance of confined space permits

• Follow the steps for safely entering a confined space

ASH page 84


ObjectivesUpon completion of this course, employees will be able to:• Know the requirements for confined space

entry in the Alaska Safety Handbook (ASH)• Properly identify confined space hazards• Institute appropriate controls, safeguards, and

actions to protect personnel• Know what additional permits are required

ASH page 85


Course Limitations

• This is not “competent person” training.

• This is an introductory course on confined space entry for authorized users.

• Additional site-specific training will be required by your company.

• The brand and type of equipment used in this class may differ from the equipment used on your job site.



10

Definitions


What is a Confined Space?

• A confined space is large enough and so configured that an employee can bodily enter and perform work; AND

• Has limited or restricted means for entry or exit (e.g. tanks, vessels, silos, storage bins, hoppers, vaults, and pits); AND

• Is not designed for continuous occupancy.

ASH page 84


Confined Space Examples

• Small, narrow or cramped passageways

• Entry or exit is by means of a ladder

• Other equipment in the space may make evacuation and rescue difficult


Is this a confined space?


Has this worker entered the confined space?


He has entered the space.


Confined Space Entry

All confined space entry on the North Slope requires a permit

•Non-hazardous CSE = Unit Work Permit•Hazardous CSE = Confined Space Entry Permit

21

ASH pages 60; 81


ASH page 84OSHA 29CFR1910.146(b)

When Is a Confined Space Entry Permit Required?

• Potential hazardous atmosphere, OR

• Contains material with potential to engulf an entrant; OR

• Has an internal configuration that could trap or cause asphyxiation; OR

• Contains other recognized serious safety or health hazards.


Internal Configuration – Dust Filter


ASH page 85

Hazardous Atmosphere Definition

A hazardous atmosphere is one which may expose employees to the risk of: • death, • incapacitation, • impairment of ability to self-rescue,• injury, or acute illness.


Hazardous Atmosphere

• Flammable gas, vapor, mist in excess of 10% of its LEL

• Atmospheric oxygen concentration below 19.5% or above 23.5%

• Toxics or hazardous substance in excess of the PEL

• Any other atmospheric condition that is IDLH

ASH page 85


ASH page 84OSHA 1910.146

Engulfment

• Engulfment results when a worker is surrounded and overcome by substances such as soil, sand, gravel, sludge or is submerged in a liquid or a flowable solid substance.

• Engulfment causes injury or death by constriction, crushing or strangulation.


Engulfment – Oil, Water, Solids



28

Hazard Assessment, Mitigation and Control


Job Steps for CSE Decision-making

• Hazard Assessment, Mitigation, Control

• Testing/Monitoring

• Permitting

• Pre-entry Preparation: Isolate and Clear

• Work Activity

• Permit Closure and Documentation


Hazard Assessment

All work to be performed inside and outside a confined space must be identified and evaluated the same as potential hazards presented by the original space contents.


Task Hazard Analysis (THA)

• Provides a company with a specific process or steps for:– Identifying known and potential hazards.– Identifying methods to reduce or eliminate

them

• Every company has different forms known by different names (THA, JHA, JSA).


Sample THA

ASH page 71


Sample JHA



34

Types of Hazards


Types of Hazards

• Energy sources (internal or external to the confined space)

• Worker introduced (internal to the confined space)

• Other hazards external to the confined space


Energy Source Hazards

Any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal or other energy.

ASH page 111OSHA 1910.147(b)


Electrical Energy Hazards

• Power lines

• Heat trace

• Static electricity

• Power tools

• Welding cables

• Grounding and bonding cables

ASH page 111


Residual or Stored Energy Hazards

• Seized machinery

• Stuck valves

• Belts and flywheels

• Spring-operated valves

• Backup generators or batteries

• Capacitors

• Springs

ASH page 111


Pressurized Energy Hazards

• Pumping operations

• Pressure testing

• Pressurized cylinders

• Hydraulic lines/equipment

• Pneumatic systems

• Circulating systems

ASH page 112


Momentum/Gravity Hazards

• Materials suspended from a crane

• Working at heights

• Slippery surfaces

• Blocks, cribbing, chains, pins

• Running machinery

• Cutting actions

ASH page 112


Special Energy Hazards

• Heat/cold (e.g., hot process piping, steam systems, frostbite, welding operations, fired heaters)

• Fuel systems and chemical treatment systems

• Radiation

ASH page 111


Worker Introduced Hazards

• Paint, solvents, thinners

• Fumes from welding and cutting operations

• Dust (including silica) from sandblasting, grinding and sweeping

• Adhesives

ASH page 111


Worker Introduced Hazards

• Electrical equipment/tools

• Non-bonded and/or ungrounded cleaning equipment (e.g., hoses)

• Noise from running equipment

• Inadequate lighting


Hazards External to the Space

Work that could be distracting to the attendant, cause delay in summoning rescue services or add hazards: • Work on the exterior of the confined space• Other project construction• Hot work in the area (cutting or grinding)


Hazards External to the Space

• Traffic for the project or other projects in the area (equipment, pedestrians, observers)

• Radiation (e.g., x-ray activity)

• Noise, heat, or cold

• Vehicles, heaters, compressors, or welding equipment that generate fumes, gases or vapors which could be drawn into the space


What are the hazards?


Walking/Working Surface Hazards

• Lighting levels and number of fixtures

• Tripping hazards or slippery/uneven surfaces, entanglement

• Overhead piping, low ceilings or overhanging roof


Equipment and Tools

Gather and inspect required tools and equipment

• Cleaning materials and current MSDS• Equipment is undamaged • Whip-checks are attached • Equipment correctly placed• Drip-pans


Other Recognized Hazards

• Turning and/or exposed blades on equipment

• Falls from ladders into a tight place or hole where the worker could drop to another level

• Uneven floors, wet surfaces, poor lighting

• Molds, mildew, bacteria in sewage, rodents and insects


Other Recognized Hazards

• Extremely hot or cold temperatures

• Dehydration and physical stress from hard work

• Hardhats, respirators dislodged by pipes, ballasts, and other obstacles in the space

• Noise levels amplified due to confined space



54

Atmospheric Testing/Monitoring




• Testing/Monitoring• Permitting


• Work Activity



Testing from Outside the CS

Test the atmosphere at several levels from outside the confined space through wall openings and roof hatches:

• At the top of the confined space and at intermediate points

• In breathing zones• Near floor and other low points (i.e., sumps)

ASH page 97


Atmospheric Testing

TOP

MIDDLE

BOTTOM

• Sample When / Where?– Prior to entry

• Top, middle & bottom • Continuously during entry

– Prior to re-entry

• Sample Why?– Stratification / Weights / Mix


Atmospheric Testing

METHANE (lighter than air) CARBON MONOXIDE (slightly lighter than air)

HYDROGEN SULFIDE (heavier than air)


Atmospheric Testing

• Hazardous conditions can exist ANYWHEREANYWHERE and at ANYTIMEANYTIME

• Never trust your SENSESSENSES.

• Always use a calibrated gas detection instrument

• Must be performed by a competent person


Testing Sequence

ASH page 97

1. Test for oxygen.

2. Test for flammables.

3. Test for toxics.


Acceptable O2 Levels

Atmospheric concentrations between 19.5% and 23.5%

61


Oxygen Deficient or Enriched Atmospheres

• Oxygen Deficient: Any atmosphere that has less than 19.5% O2 by volume

• Oxygen Enriched: Any atmosphere that has greater than 23.5% O2 by volume

Deficient< 19.5%

Normal20.9%

Enriched> 23.5%


Range of O2 Levels

23.5%

20.9%19.5%

15.0%

10.0%

Normal level

Do not enter enriched atmosphere above 23.5%

Do not enter below 19.5% . Air supply required if entry permitted.

Significant physical impairment, loss of coordination, slurring of speech, impaired

judgment

Below 10%, nausea,

vomiting, death

O2%

23%

21%

19%

15%

10%


Oxygen Deficient Atmosphere

What are some causes?• Displacement• Chemical exposure to

gases which reduce or stop the body’s ability to use oxygen (even if oxygen is present in the air)

• Aerobic bacteria have used up the oxygen


Oxygen Enriched Atmosphere

What are some possible causes?• Leaking oxygen supply such as welding

equipment• Chemical action of oxidizers or organic peroxides• Original contents of vessel


Oxygen Levels

• An oxygen level above 23.5% causes flammable and combustible materials to burn violently when ignited:– Hair, clothing, materials, etc.– Oil soaked clothing and materials

• Never use pure oxygen to ventilate

• Never store or place compressed tanks in a confined space


Fire Triangle and Tetrahedron

What is the difference between the fire triangle and the tetrahedron?


Causes of Flammable Atmospheres in Confined Spaces• Inadequate isolation of the space from

combustible or flammable material sources

• Insufficient draining of flammable liquids

• Insufficient ventilation and/or purging with an inert gas


Causes of Flammable Atmospheres in Confined Spaces• Production of gas such as methane from

bacterial action

• Leaking gas from outside the confined space migrating into the space

• Other worker-induced chemicals (cleaners, paints)


Flammability

• Ability to ignite or burn, measured in percent (%) of LEL

• What is the definition of LEL?

• Flammable Range is between the LEL and UEL

• What is the definition of UEL?


Flammability Range

LEL= 5.3%

UEL= 15%

Too Rich

Too Lean

Explosive Mixture

Example: (Natural Gas)

Methane (CH4)


Testing for Flammables

• Flammable gas, vapor, or mist in excess of 10% (>10%) of its LEL

• Airborne combustible dust in a concentration that meets or exceeds its LEL

• Flammable vapors must be less than 50% LEL to completely remove a hatch or man-way in a facility.

ASH, page 87


What Are Toxic Contaminants?

• Toxics are poisons

• A toxic may be any substance which has the potential to:– Cause death– Incapacitation– Injury– Illness


Examples of Toxic Contaminants

An atmosphere may contain excessive levels of toxic gases, vapors, mists and/or dusts hazardous to personnel (8 hr TWA)

Hydrogen Sulfide 10ppm (AKOSH)

Carbon Monoxide 35ppm (AKOSH)

Inert or nuisance dust 5mg/m3 (PEL)

Benzene 1ppm (PEL)

Sulfur Dioxide 2ppm (AKOSH)

Welding fumes 5mg/m3 (AKOSH)


Toxic ContaminantsExposure levels are set by governmental agencies and company policy

• PEL: (OSHA)• TLV-TWA: (ACGIH)• STEL: (OSHA and ACGIH)• IDLH: (NIOSH)


Exposure Limits for Toxic Contaminants

• PEL 8 hrs per day, or 40 hrs per week

• TLV 8 hrs per day, or 40 hrs per week

• STEL 15 minutes, maximum; 4 times per day; each exposure must be separated by an hour

• IDLH Air supplied respirator

REMEMBER to read the MSDS.


Symptoms from Over Exposure

• Acute – Short term – more immediate reaction– Occurs rapidly within a short period of time

• Chronic – Long term – less immediate reaction– Occurs slowly over a longer period of time


Acute Symptoms

• Eye, ear, throat and/or skin irritation

• Dizziness

• Headache or “light-headed” feeling

• Shortness of breath-difficult breathing

• Unconsciousness

REMEMBER to read the MSDS first.


Chronic Conditions

• Lung damage

• Liver disease

• Kidney disease

• Disorders of the Central Nervous System (CNS)

• Cancer

REMEMBER to read the MSDS first.



80

Confined Space Permits





• Permitting• Pre-entry Preparation: Isolate and Clear

• Work Activity



Permit Initiation

Permits may be initiated by anyone and will be done at the appropriate Control Room or other designated location.

ASH page 85


Why Have a Permit?

• ALLOWS and CONTROLS ENTRY into a space that may cause death or serious injuries to workers

• Ensures employees can SAFELY ENTER INTO and WORK WITHIN the space

• Ensures coordination and cooperation and safety of workers between other projects

• By law, company programs cannot fall below OSHA requirements, but they can exceed them.


Confined Space vs. Hazardous Confined Space

Confined Space Definition Hazardous Confined Space

Large enough and configured so workers can bodily enter and perform assigned work, AND Same as Confined Space

Has limited or restricted means for entry and exit, AND Same as Confined Space

Is not designed for continuous employee occupancy Same as Confined Space

AND, has one or more of the following:

Contains or has the potential to contain a hazardous atmosphere, OR

Contains material that has the potential to engulf the entrant, OR

Has an internal configuration such that the entrant could be asphyxiated by inwardly converging walls or a floor that slopes downward and tapers to a smaller cross-section, OR

Contains any other recognized serious safety or health hazard


What permit is required to enter this tank?


What permit is required to enter spaces under the tank?


What permit is required to enter this space?


OSHA and ASH Permit Requirements

• Any worker, who works under the guidance of the Alaska Safety Handbook (ASH), will be issued a permit prior to start of work and will work according to the permit instructions.

• Workers in a non-hazardous confined space will be issued, at a minimum, a Unit Permit, and possible additional permits depending on other work in progress.

ASH page 55, 63 & 84


Unit Work Permit

Non-Hazardous

Confined Space Entry

Requires a

Unit Work Permit

REMEMBER: Any work requires a permit (i.e., a project can consist of multiple tasks needing various types of permits)

ASH page 60–63, 84


Confined Space Entry Permit

HazardousConfined Space Entry

Requires a

Confined Space

Entry Permit

REMEMBER: Any work requires a permit. The CSE Permit does not always authorize work to begin. It may need to be accompanied by other permits.

ASH page 81–88


Hot Work Permit

Depending on the work,

additional permits may

be required such as a

Hot Work Permit.

ASH page 69–80


Process Opening/Blinding Permit

Depending on the work,

additional permits may

be required such as a

Process Opening and

Blinding Permit.

ASH page 119–127



93

Pre-Entry Preparation





• Permitting


• Work Activity




95

Isolating the Confined Space


Isolating the Confined Space

Remove or bring awareness of external hazards to workers by following:

• Energy Isolation Standard- ASH, pages 101–121

• Process Opening and Blinding Standard- ASH, pages 122–127


Double Block & BleedNot an approved isolation for confined

space entry

1 2 3 4

ASH page 126

Pressure Source

Site of Line Opening

Pressure Source

Bleed Point BStep 1 Close valves 1 & 4

Step 2 Bleed at bleed points A & B

Step 3 Close Valves 2 & 3

Bleed Point A

97



98

Clearing the Confined Space


Preparation for Clearing the Space

Prior to opening a vent/hole/pipe into a confined space

• Read the MSDS on the substance to determine what, if any, PPE (clothing) is required.

• Conduct atmospheric monitoring for respiratory and flammable hazards


Basic Steps for Clearing the Space

• Remove the substances that are inside the confined space.

• Inert, purge and ventilate the air to remove flammable and atmospheric hazards.

• Conduct atmospheric testing inside the space prior to entry.

• Clean inside the confined space (water washing, flushing, or steaming).

ASH page 86–88


Inerting and Purging

• Inerting involves removing oxygen from a CS using an inert gas (nitrogen) so the atmosphere is no longer within flammable limits (oxygen deficient).

• Purging involves removing contaminants inside the CS by displacement with another gas or vapor to achieve acceptable atmospheric levels.


Purging Considerations• Source: Ensure supply air is not contaminated with

hazards in the atmosphere (diesel, dust)

• Exhaust: If the contaminant is flammable or toxic, you must control the exhaust AND establish control zones for individuals working near the confined space


Ventilation

ASH page 87, paragraph 6


Ventilation


Ventilation

Ventilation means the continuous provision of fresh air into the Confined Space by mechanical means to maintain acceptable atmospheric levels.


Ventilation• Natural Ventilation is

unreliable and mostly uncontrollable.

• Mechanical ventilation– Electrical– Hydraulic– Pneumatic

• Methods– Positive-Forced air– Negative-Exhaust air– Combination

ASH page 88, #8


Positive Ventilation

• Pushes / forces air into the CS– Air exits the CS “naturally”

– Air must be exchanged on a regular schedule determined by a complete and accurate atmosphere evaluation by qualified personnel

• How effective is positive ventilation?


Negative Ventilation

• Pulls air from the CS – Pulls contaminants across

fan and motor, may require decontamination

– Equipment must be certified intrinsically safe if removing flammable contaminant

• How effective is negative ventilation?


Positive/Negative Ventilation

Pulls and pushes air into and out of the CS


Positive – Negative Ventilation

Channeling across the space


What Makes Ventilation Effective?

• Generally, 5 air changes will reduce a contaminant to approximately 10% of its original concentration.

• Positive pressure is more effective.


Example – Slug Catcher Ventilation Diagram


Clean from Outside of CS


Clean from the Outside



115

Confined Space Work Activity





• Permitting


• Work Activity• Permit Closure and Documentation


Work Activity – CSE Entry Team

Confined Space Entry Team– Entry Supervisor– Authorized Entrant– Attendant– Rescue Service / Rescuer

ASH page 93


CSE Entry Team Responsibilities

Responsibilities for confined space work are clearly defined in the Alaska Safety Handbook.


Entry Supervisor

ASH page 93–94


Entry Supervisor

What duties does the Entry Supervisor perform related to:• Hazard assessment?• Communication with entrants or unauthorized

persons?• The permit under which the work is being

completed?• Monitoring the work?• Rescue Services?• At the end of the shift?

ASH page 93–94


Authorized Entrant

ASH page 94–95


ASH page 94–95

Authorized Entrant

What duties does the Authorized Entrant perform related to:• Energy isolation?• Hazard assessment and testing?• The permit under which the work is being

completed?• Personal protective equipment?• Communication with other members of the

Entry Team?• The end of the shift?


Attendant

ASH page 95–96


Attendant

• What is the primary function of the Attendant?• What duties does the Attendant perform

related to:– Hazard assessment and monitoring?– The permit under which the work is being

completed?– Recordkeeping?– Communication with members of the Entry Team

and warn unauthorized persons away from the space?

– Rescue services?

ASH page 95–96


Rescue Services / Rescuer


ASH page 88, #10

Rescue Services / Rescuer

Each member of the Rescue Service or team has specialized training and practice• Rescue in the specific type of space to be

encountered• Authorized Entrant training• Use of PPE required for rescue• Use of specialized rescue equipment• Actual entry rescue training every 12 months• Basic First Aid and CPR


Tripod Rescue System


Other Personnel Responsibilities

• Unit Operator/Issuing Authority

• Control Room Operator or Drillsite/Wellpad Operator

• First-line Supervisor

• Company Safety Personnel

ASH page 86, 91–92, 96


Work Activities

Pre-Job Safety Plan• Establishes a structure / outline by which the

employer / contractor defines how safety will be managed

• Provides a mechanism by which the hazard exposures and the duties of all those involved can be specifically defined

• (Refer to company site-specific plan for more information.)



130


Permit Closure and Documentation



• Hazard Assessment, Mitigation, Control• Testing/Monitoring• Permitting• Pre-entry Preparation: Isolate and Clear• Work Activity• Permit Closure and Documentation


Permit Duration and Close-out

• Permits will be in effect until the job is completed but will not extend past the end of the shift during which they were issued.

• If a change in any conditions listed on the permit results in unacceptable conditions, work must cease, the permit is invalid, and must be re-issued.

ASH page 98, #2–3


Permit Duration and Close-out

• If the Entrant, Attendant, or Entry Supervisor perceive an abnormality (work, worker behavior, outside influences, etc.), regarding the CS, evacuation is initiated, work ceases, and the permit becomes invalid and must be reissued.

• If rescue or emergency services become unavailable, all work in the space is suspended and occupants evacuate.

ASH page 98, #2


General Permitting Rules

• Any individual may invalidate a work permit at any time if they consider the conditions or work methods to be unsafe.

• The issuing Authority will address the concern, inspect the work site, and decide whether the permit should be revalidated.

ASH page 55, #2 & 4


Documentation

• All Confined Space Entry Permits MUST be officially closed out by the signature of the Entry Supervisor or their designee on the permit.

• Any problems encountered during an entry operation shall be noted on the permit so that appropriate revisions can be made to the permit.

ASH page 57, #11


Documentation

• The copy of record of all permits shall be retained for a period of time (one year) as specified by company policy.

• OSHA requires an annual review of confined space program.

ASH page 57, #12


Summary

• Prior to entry – evaluate and eliminate hazards

• Remaining hazards – test, assess and control

• Structure work and personnel according to plans and procedures

• Work to appropriate permits

• Know how to respond to emergencies

• Finalize the work – close permits and document


Exercises

Instructions: Working in small groups answer the following questions for your assigned exercise.• Is this a confined space? Why?• What kind of permits are required?• What are the potential hazards?• How would you isolate and clear the area?• What kind of emergencies would you anticipate

and what procedures would you follow?


Exercise 1

Task: Clean out the solids from bottom of the sump with a shovel.


Exercise 2

Job: Inspect interior of knockout drum, and install corrosion probe.

soffit

valve

valve

manhole

valve

valve

weld-a-let


Exercise 3

Job: An old well is being abandoned. The casing is to be cut off below the ground level and the excavation backfilled. The well bore has already been cemented off as indicated.

Cemented Well Bore

Excavation below ground level

Cut line


Exercise 4

Job: Repair a weld in piping. Welding is done from outside the piping. Inspectors will inspect the welds from inside the pipe.

Blind 1/4 mile upstream

QA/QC inspectors entrance point

Bleed Points

Roadway

Blind

48” pipe

revised: september 2009 copyright ©1997-2009—all rights reserved north slope training cooperative...

Documents

confined space entry

course overview slide

course limitations

introductory course

confined space fatalities

confined space ash page

confined spaces

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