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Executive Health and Safety

Whole-body vibration and ergonomics of driving occupations Phase 2: Port vehicles

Prepared by the Health and Safety Laboratory for the Health and Safety Executive 2008

RR613 Research Report



A M Darby BSc(Hons) MSc CPhys MInsP P M Pitts BSc(Hons) MIOA Health and Safety Laboratory Harpur Hill Buxton SK17 9JN

Back disorders are the most common form of ill health at work and this is one reason why HSE has made reducing their prevalence a priority.

The work reported here is the second part of a project looking at whole-body vibration exposure and other ergonomic risk factors for back pain from driving occupations. Phase 1 of the project is reported in RR612. The project is an exploratory study of back pain in drivers. The small sample size of the study means that it will not be possible to draw strong conclusions about relationships between exposure data and self-reported musculoskeletal disorders. However as future studies use the data collection toolkit developed during this project to add to the library of data, it will be possible to analyse the records for evidence of possible combined effects of whole-body vibration and ergonomic stressors as sources of back pain.

Phase 2 of the project, essentially a data gathering exercise, involved applying the toolkit to a number of vehicles. The part of Phase 2 concerned with port vehicles is reported here. Eight port vehicles were studied for this part of the project.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

HSE Books

© Crown copyright 2008

First published 2008

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the prior written permission of the copyright owner.

Applications for reproduction should be made in writing to:Licensing Division, Her Majesty’s Stationery Office,St Clements House, 2-16 Colegate, Norwich NR3 1BQor by e-mail to [email protected]

ii

CONTENTS

1 INTRODUCTION......................................................................................... 1

2 HEALTH QUESTIONNAIRE RESPONSES................................................ 22.1 General Demographics............................................................................ 22.2 Work Characteristic Factor (WCF) or ‘Psychosocial’ Scores ................... 22.3 Musculoskeletal Disorders....................................................................... 4

3 MEASUREMENTS AND ANALYSES......................................................... 83.1 Vehicles ................................................................................................... 83.2 Cab ‘Fit’ ................................................................................................... 93.3 Posture .................................................................................................. 103.4 Manual handling .................................................................................... 103.5 Vibration ................................................................................................ 10

4 RESULTS ................................................................................................. 12

5 DISCUSSION............................................................................................ 195.1 Cab ’fit’................................................................................................... 195.2 Posture .................................................................................................. 195.3 Manual handling .................................................................................... 195.4 Vibration exposures ............................................................................... 195.5 Seat back vibration levels ...................................................................... 205.6 Spine response method (ISO 2631-5) ................................................... 20

6 CONCLUSIONS........................................................................................ 22

7 REFERENCES.......................................................................................... 23

APPENDIX A. EQUIPMENT ........................................................................... 24

APPENDIX B. HYSTER FORK LIFT TRUCK................................................. 25

APPENDIX C. KOMATSU FRONT END LOADER ........................................ 31

APPENDIX D. MORRIS RAIL MOUNTED GANTRY CRANE ........................ 37

APPENDIX E. KALMAR TRX 182 TRACTOR................................................ 42

APPENDIX F. RUBBER TYRED GANTRY CRANE....................................... 50

APPENDIX G. LINDE FORK LIFT TRUCK .................................................... 54

APPENDIX H. LINDE MOBILE CONTAINER HANDLER .............................. 68

APPENDIX I. HARBOUR LAUNCH................................................................ 78

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EXECUTIVE SUMMARY


The work reported here is the second part of a project looking at whole-body vibration exposure and other ergonomic risk factors for back pain from driving occupations. Phase 1 of the project is reported in Darby, 2006. The project is an exploratory study of back pain in drivers. The small sample size of the study means that it will not be possible to draw strong conclusions about relationships between exposure data and self-reported musculoskeletal disorders. However as future studies use the data collection toolkit developed during this project to add to the library of data, it will be possible to analyse the records for evidence of possible combined effects of whole-body vibration and ergonomic stressors as sources of back pain.

Phase 2 of the project, essentially a data gathering exercise, involved applying the toolkit to a number of vehicles. The part of Phase 2 concerned with port vehicles is reported here, while that part concerned with forestry vehicles is reported in Pitts, 2007. Eight port vehicles were studied for this part of the project.

Main Findings

The only noteworthy postural issues found were the frequently adopted twisted reversing posture of the Hyster fork lift truck driver, and the forward bent postures adopted by the gantry crane drivers when lifting and lowering containers.

No major manual handling issues were found in the driving jobs studied, which involved virtually zero manual handling.

Some weaknesses were found with the cab designs, however no major problems were identified. Weakness included an inadequate range of seat height adjustment for shorter operators and several of the seats having too great a seat depth, hindering easy use of the backrest by some of the operators.

Operators of the Hyster fork lift truck, the Morris rail mounted gantry crane, the Kalmar tractor, and the Morris rubber tyred gantry crane had likely vibration exposures below the daily exposure action value of 0.5 m/s² A(8) in the Control of Vibration at Work Regulations 2005.

Estimates of the likely A(8) exposures of the operators of the Komatsu front end loader, and the Linde fork lift truck and Linde mobile container handler were between the exposure action value and the limit value in the Regulations.

Most of the daily Vibration Dose Value (VDV) exposures for the vehicles in the study appeared generally to be below HSE’s guidance figure of 17 m/s1.75. On the day of the measurements the daily exposure for drivers of the mobile container handler greatly exceeded the guidance figure. However as the damper on the seat of this vehicle was broken, the estimated daily exposures for this vehicle were much higher than they would normally have been.

The performance of the seats on the two fork lift trucks was good, the two seats attenuating both the A(8) and daily VDV exposures. The seats on the two gantry cranes slightly amplified the exposure of the operators. However the vibration levels from the cranes were so low that it would be unreasonable to expect those seats to work properly and to attenuate incident

v

vibration. (A certain level of vibration is needed to overcome friction.) The seat on the front end loader and on the tractor unit had little effect on the vibration exposure of the drivers.

The seat back vibration levels measured were comparable to the highest vibration levels on the seat pan, indicating that seat back vibration data should continue to be gathered, as it may be important when considering adverse health effects.

For the data considered here the spine response metric tells a broadly similar story to the VDV metric. In most cases vehicles that gave a low risk according to the VDV metric also gave a low risk according to the spine response metric.

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1 INTRODUCTION


The exact cause of back pain is often unclear but back pain is more common in jobs that involve driving, especially over long distances or over rough ground. Driving exposes the vehicle’s occupants to whole-body vibration, and possibly shocks and jolts, factors that are believed to increase the likelihood of injury or pain in the lower back. However drivers may also be exposed to other risk factors for lower-back pain such as poor posture while driving and manual handling while loading and unloading goods.

The work reported here is the second part of a project looking at whole-body vibration exposure and other ergonomic risk factors for back pain from driving occupations. Phase 1 of the project is reported in Darby, 2006. The project is an exploratory study of back pain in drivers. The small sample size of the study means that it will not be possible to draw strong conclusions about relationships between exposure data and self-reported musculoskeletal disorders. However as future studies use the data collection toolkit developed during this project to add to the library of data, it will be possible to analyse the records for evidence of possible combined effects of whole-body vibration and ergonomic stressors as sources of back pain.

Phase 2 of the project, essentially a data gathering exercise, involves applying the toolkit to a number of vehicles. The part of Phase 2 concerned with port vehicles is reported here, while that part concerned with forestry vehicles is reported in Pitts, 2007.

1

2 HEALTH QUESTIONNAIRE RESPONSES

The cargo handlers completed ten health questionnaires. As there were only a small number of questionnaires to analyse, the findings reported in this section are not statistically significant, and should be regarded as indicative only.

2.1 GENERAL DEMOGRAPHICS

The basic demographics statistics taken from the questionnaires are given in Table 1.

Table 1. Cargo handlers group characteristics

Mean (& Standard Deviation)

Minimum Maximum

Age (years) 46.4 (6.8) 38.1 59.9

Weight 88.3kg (17.9) 13st 13lb

65.8kg 10st 5lb

127.0kg 19st 13lb

Height 180.1cm (7.2)

5’ 11’’

172.7cm

5’8’’

195.6cm

6’5’’

Body Mass Index (BMI)1 27.2 (4.9) 21.4 38.0

Years doing job 13.7 0.1 26.3

Weekly working hours 45.5 (3.0) 39.0 50.0

Total time in vehicle during day

4 hr 57 min

(1 hr 4 mins) 3hr 7hr

Maximum time in vehicle in a single session 4 hr 48 mins 3hr 7hr

Smokers 1 smoker (10% of sample)

1 BMI is an indicator of total body fat calculated using height and weight. The cargo handler group’s value of 27.2 lies within the range 25 to 30, which has

been classified as ‘overweight’. Although the ‘normal’ BMI range is 20 to 25, BMI is not a measure of fitness and the classification term ‘overweight’ can sometimes

be misleading.

WORK CHARACTERISTIC FACTOR (WCF) OR ‘PSYCHOSOCIAL’ SCORES

The cargo handlers were asked to rate five statements on each of six aspects of their work in terms of whether they strongly agreed or disagreed with them. For example the Work

2

2.2

Autonomy factor contained the statement “you can influence your working methods”: Strongly agree (scored 1) to Strongly disagree (scored 5).

The six aspects of work were:

o Work Autonomy (WCF1) Influence on and control over work. Influence on: rate of work, working methods, task allocation, technical control, and rules and regulations.

o Supervisor Climate (WCF2) Levels of contact with immediate supervisor, whether supervisor asks for opinions or input, considers input from others, provides information and the general communication climate within the organisation.

o Work Variety (WCF3) Whether the work is stimulating, interesting, varied, diversified, taxing (opportunity to use new skills and talents), offers learning opportunities, general feeling about work.

o Peer Group Support (WCF4) Relationships and contacts with fellow workers, talking with fellow workers, cheeriness of atmosphere at work, regarding fellow workers as good friends or not.

o Stress levels / psychological workload (WCF5) Stress at work, workload, extent of feeling tired and exhausted after work, possibility of relaxing and having a break, and mental strain.

o Management commitment to health and safety (WCF6) Perceived levels of employer concern about health and safety, importance of reporting accidents, ensuring a safe worksite, regularly checking up on whether work is making you ill, and ensuring health and safety rules are followed.

The mean and 95% Confidence Interval of the mean score for each of these aspects of work is shown in Figure 1. The higher scores show more positive attitudes to each work characteristic factor or aspect of work. The most negative possible score is 5 and the most positive possible score is 25. A score of 15 indicates neutrality of opinion.

Also shown in Figure 1 are the means and 95% Confidence Intervals from an HSL study of 491 industrial workers (identified as “NIOSH” study) (Marlow, 2005). The cargo handlers’ scores were very similar to those for the industrial workers. All the scores were over 15, which indicates a neutral - low stress environment. This indicates that the psychosocial work environment is good overall, particularly in terms of peer group support (WCF4).

3

2.3

5

10

15

20

25

WCF1

WCF2

WCF3

WCF4

WCF5

WCF6

l

5

15 neutral

25 excellent / very low stress

Fact

or s

core

NIOSH mean

Cargo hand ers mean

very poor / high stress 10 poor / some stress

20 good / low stress

Figure 1. Work Characteristics data from HSL studies (means + 95% Confidence Intervals)

MUSCULOSKELETAL DISORDERS

The survey asked the cargo handlers whether they had experienced any musculoskeletal trouble over the previous 7 days (Figure 2) and over the previous 3 months (Figure 3). The survey also asked whether the musculoskeletal disorder(s) caused any activity restriction over the last 3 months (Figure 4), and whether the cargo handlers thought the job had contributed to the problem over the last 3 months (Figure 5).

The prevalence data shows that half the cargo handlers reporting musculoskeletal trouble in the lower back in the previous 3 months. Half the cargo handlers also reported neck problems in the previous 3 months. (There were only ten questionnaires for the cargo handlers so the findings are indicative only.)

It is possible to directly compare the 3-month data with 12-month pain prevalence levels from previous studies of different populations (Marlow, 2005). The data for the cargo handlers has been compared with 12-month data from a group of lorry drivers and 12-month general population data (Darby, Jackson and Milne, 2002).

Figure 6 shows that compared to the general and lorry driving populations the cargo handlers studied reported higher levels of musculoskeletal trouble in the neck (26% more and 19% more respectively). 9% more cargo handlers than members of the general population reported suffering from lower back problems.

4

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

Neck

Should

ers

Elbows

Wris

ts / h

ands

Upper

back

Lower

back

Hips/Thig

hs/B

uttoc

ks

Knees

Ankles

/Feet

Perc

enta

ge o

f res

pond

ants

Figure 2. Cargo handlers’ 7-day pain prevalence

100.0 90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0

0.0

Neck

Should

ers

Elbows

rists

/ han

ds

Upper

back

Lower

back

Hips/Thig

hs/B

uttoc

ks

Knees

nkles

/Feet

AW

Figure 3. Cargo handlers’ 3 month MSD prevalence

Perc

enta

ge o

f res

pond

ants

5

Perc

enta

ge o

f res

pond

ants

100.0

90.0

80.0

70.0

60.0

50.0

40.0

30.0

20.0

10.0

0.0

Neck

Should

ers

Elbows

Wris

ts / h

ands

Upper

back

Hips/Thig

hs/B

uttoc

ks

Lower

back

Knees

Ankles

/Feet

Figure 4. Cargo handlers: Activity restriction in last 3 months

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

Neck

Should

ers

Elbows

Wris

ts / h

ands

Upper

back

Lower

back

Hips/Thig

hs/B

uttoc

ks

Knees

Ankles

/Feet

Perc

enta

ge o

f res

pond

ants

Figure 5. Cargo handlers: Job contributing to problem in last 3 months

6

0

10

20

30

40

50

60

70

80

90

100

Neck

Should

ers

Elbows

Wris

ts/Han

ds

Upper

back

Lower

back

Hip Thig

h Butt

ock

Knees

Ankles

/ Fee

t

Perc

enta

ge re

port

ing

pain

G ener al Population ( 12 m onth data)

Car go handler s

Lor Dr iver s ( 12 m onth data)r y

Figure 6. Pain prevalence data for general population (12-month prevalence), cargo handlers (3-month prevalence) and lorry drivers (12-month prevalence)

7

3 MEASUREMENTS AND ANALYSES

3.1 VEHICLES

All the measurements were made on 21st and 22nd November 2006, at the same port. The vehicles studied for this part of Phase 2 of the project are shown in Table 2.

Table 2. Vehicles and tasks

Vehicle Task

Hyster fork lift truck Moving fertilizer bags, lots of twisting for forward / reverse driving

Komatsu front end loader Moving loose fertilizer, some twisting for forward / reverse driving

Morris rail mounted gantry crane Moving containers, ladder access to gantry crane

Loading 6.00pm Ro-Ro ferry

Kalmar TRX 182 tractor

Loading midnight Ro-Ro ferry

Morris rubber-tyred gantry crane Moving containers, ladder access to gantry crane

Travelling to brick yard

Linde FLT H40D Loading bricks onto lorry

Travelling back from brick yard

Moving containers

Linde mobile container handler

Travelling

Harbour launch Travelling around the harbour

8

3.2 CAB ‘FIT’

The anthropometric assessment was intended to identify marked mismatches between the cab dimensions and the relevant anthropometric dimensions of the selected population. Seat dimensions and reach parameters were recorded and an anthropometric spreadsheet used to determine the percentage of the chosen population that could be accommodated by the seating. The populations chosen were UK 18 to 65 year old males and UK 18 to 65 year old females.

The dimensions recorded were:

Seat:

Dimensions v and h (see Figure 7): used to find the accommodated buttock to ankle length assuming both an optimum knee angle for a light pedal force (less than 100N) and an optimum knee angle for a strong pedal force (greater than 100N).

v h

Figure 7. Seat to pedal distances

o Seat pan height at front: for comparison with popliteal (back of knee) height

o Seat pan depth: for comparison with buttock to popliteal length

o Seat pan width: for comparison with hip breadth

o Back rest height: for comparison with sitting shoulder height

o Back rest width: for comparison with chest breadth at nipple

o Head rest height + seat back height: for comparison with sitting height

Steering Wheel:

o Top centre of seat back to top of steering wheel: for comparison with forward grip reach

o Seat pan to steering wheel: for comparison with thigh depth

Gear Lever:

o Top of seat back nearest gear lever to top of gear lever: for comparison with forward grip reach

9

Hand Brake:

o Top of seat back nearest hand brake to front of hand brake: for comparison with forward grip reach

3.3 POSTURE

Where possible, the driver’s postures and actions while working were videoed for later analysis. After the site visit the video was analysed to identify postures that are associated with increased risk of musculoskeletal disorders using the Rapid Upper Limb Assessment (RULA) tool (McAtamney, L. and Corlett, E.N. 1993). This tool gives an action level with an indication of urgency.

The action levels are:

• Action level 1 indicates that the posture is acceptable if it is not maintained or repeated for long periods;

• Action level 2 indicates that further investigation is needed and changes may be required;

• Action level 3 indicates that investigation and changes are required soon;

• Action level 4 indicates that investigation and changes are required immediately.

3.4 MANUAL HANDLING

Manual handling tasks carried out by the operator were identified and rated using HSE’s Manual Handling Assessment Chart (MAC) tool (www.hse.gov.uk/msd). The MAC tool incorporates a colour coding score system to highlight high-risk elements in manual handling tasks (green – low level of risk, amber – medium level of risk, red – high level of risk, purple – very high level of risk).

3.5 VIBRATION

The vibration levels were measured on the seat pan, in the three orthogonal directions shown in Figure 8, both on and below the suspension seat:

o x-axis fore-aft relative to the seat Z

o y-axis across (side-to-side) the seat Y o z-axis vertical X

Figure 8. Measurement axes

Where possible the vibration levels were also measured on the seat back in the direction of travel.

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The vibration measurements were made for a representative period of the machine operator’s working day and the daily exposure time used to estimate the operator’s daily vibration exposure. Worst-case exposure times were used.

All measurements were made in accordance with ISO 2631:1997. Details of the equipment used for the measurements are given in Appendix A.

Once collected the vibration data was analysed to provide the following metrics for each of the seven channels of data (three on the seat, three below the seat, and one on the seat back):

o acceleration power spectral density;

o r.m.s. (unweighted) level;

o r.m.s. frequency weighted level (ISO 2631-1:1997);

o VDV (ISO 2631-1:1997);

o eVDV (ISO 2631-1:1997);

o crest factor (defined as the frequency weighted peak / frequency weighted r.m.s.) (ISO 2631-1:1997);

o MTVV linear (ISO 2631-1:1997);

o MTVV exponential (ISO 2631-1:1997).

In addition the analyses determined the:

o A(8) value (8 hour frequency weighted r.m.s. acceleration level for the working day);

o the working times to reach the exposure action and limit values in the Control of Vibration at Work Regulations 2005;

o VDV exposure for the working day (VDVexp);

o the working time to reach a daily VDV exposure of 17 m/s1.75 (HSE’s criterion for risk including significant shock exposure – adopted from ISO 2631-1:1997);

o Spine response parameters (ISO 2631-5:2004);

o H1 frequency response spectrum between the seat base and seat pan for each axis and associated coherence;

o r.m.s. Seat Effective Amplitude Transmissibility (SEAT) Factor for each axis;

o VDV Seat Effective Amplitude Transmissibility Factor for each axis.

Note: SEAT values greater than 1 imply amplification of vibration by the suspension system, values less than 1 imply the suspension system is reducing the vibration transmitted to the driver.

11

4 RESULTS

The results of the analyses are summarised in Tables 3 to 6. Detailed results for each vehicle are given in Appendices B to I.

The occupational data is summarised in Table 3.

The estimated daily whole body vibration exposure values (A(8) and VDVexp) for the operators are given in Table 4, together with the time taken to reach the exposure action and limit values (EAV and ELV respectively) in the Control of Vibration at Work Regulations 2005. In Table 4, the cells containing exposures lying between the action value and the limit value are outlined in amber, and those that contain exposures exceeding the limit value for HSE’s guidance figure for high levels of shock are outlined in red. It should be noted that there was no seat on the harbour launch, so the vibration levels were measured at the feet of the pilot. This data for this standing operator has been treated as in the same way as for seated operators as required by the Regulations. It should also be noted that the damper on the mobile container handler’s seat was broken and this almost certainly accounts for the very high VDV exposures estimated for the driver.

The vibration exposures from the seat back are summarised in Table 5. For comparison purposes the vibration exposures from the seat pan are also included in this table.

Vibration data analysed using the method given in ISO 2631-5:2004 (the spine response method) is summarised in Table 6. Sed is the daily equivalent static compressive dose predicted in the lumbar spine by the spine response method. R is a factor used in the assessment of the adverse health effects related to the estimated acceleration dose. It takes into account reduced strength in the spine with increasing age, and is calculated sequentially assuming that the exposure started at the age of 20. In Table 6 R is calculated based on 240 days of equal exposure per year. According to this method of evaluating shock, values of R below 0.8 indicate a low probability of an adverse health effect, values of R greater than 1.2 indicate a high probability of an adverse health effect. The cells in Table 6 are marked as described above for Table 4.

12

Table 3. Summary Of Occupational Data

Vehicle Task / Manual Posture Cab A(8) VDVexp Performance condition handling design of of surface MAC

colour / risk

RULA score / risk

activity

(m/s²) (m/s1.75) suspension

seat

activity

Hyster fork lift

truck

Moving fertilizer

bags / good

Red / occasional

manual handling of pallets.

2 / reversing

Nothing major

identified 0.45 11.2

Good, attenuating both A(8)

and VDVexp values

Slightly amplifying

Komatsu front end

loader

Moving fertilizer /

good

None identified

Nothing major

identified

Nothing major


A(8) value, slightly

attenuating VDVexp value

Morris rail

mounted gantry crane

Moving containers

/ n/a

None identified

2 / lifting and

lowering containers

Nothing major

identified 0.12 3.4

Slightly amplifying both A(8)

and VDVexp values

Kalmar TRX 182

tractor

Loading 6.00pm Ro-Ro ferry /

unknown None

identified

No assessment

made

Nothing major

identified

0.37 12.5

Amplifying both A(8)

and VDVexp values

Loading midnight Ro-Ro ferry /

unknown

0.40 11.1

Slightly attenuating A(8) value, neutral for

VDVexp value

Morris rubber tyred gantry crane

Moving containers

/ fair

None identified

2 / lifting and

lowering containers

Nothing major

identified 0.11 3.1

Amplifying both A(8)

and VDVexp values, but vibration

levels very low

13

Vehicle Task / Manual Posture Cab A(8) VDVexp Performance condition handling design of of surface MAC

colour / risk

RULA score / risk

activity

(m/s²) (m/s1.75) suspension

seat

activity

Travelling to brick yard / poor

None identified

No assessment

made 0.73 25.0

Very good, attenuating both A(8)

and VDVexp values

Linde FLT

H40D

Loading bricks

onto lorry / fair

None identified

Twisting when

reversing

Nothing major



and VDVexp values


/ poor

None identified

No assessment

made 0.59 15.8


and VDVexp values

Moving containers

/ fair

None identified

No assessment

made 0.42 24.0

n/a

n/a

Linde mobile

container handler Travelling

/ fair None

identified

No assessment

made

Nothing major

identified

0.9 34.6

Seat substantially amplifying

both vibration

exposures, probably due to a broken damper.

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Table 4. Summary Of Vibration Data – Daily Exposures (amber moderate values, red high values)

Vehicle Task / condition

Assumed exposure

Suspension seat

A(8) Time to EAV

Time to ELV

VDVexp Time to shock

of surface time performance criterion (z-axis) (see note

hr:min SEATRMS

SEATVDV m/s² hr:min hr:min m/s1.75

3)

hr:min

Hyster Moving 0.8 fork lift fertilizer 6:00 0.45 07:31 > 24 hrs 11.2 > 24 hrs

truck bags / good 0.8

Komatsu Moving 1.1 front end fertilizer / 6:00 0.60 04:11 22:05 13.6 14:47

loader good 0.9

Morris rail Moving 1.2

mounted containers / 4:00 0.12 > 24 hrs > 24 hrs 3.4 > 24 hrs gantry n/a 1.1 crane

Loading 6.00pm Ro-Ro 5:00

1.3 0.37 09:02 > 24 hrs 12.5 17:05

Kalmar

ferry / unknown

1.3

TRX 182 tractor Loading

midnight Ro-Ro 5:00

0.9 0.40 07:51 > 24 hrs 11.1 > 24 hrs

ferry / unknown

1.0

Morris rubber- Moving 1.3 tyred containers / 4:00 0.11 > 24 hrs > 24 hrs 3.1 > 24 hrs

gantry fair 1.2 crane

15

Vehicle Task / condition

Assumed exposure

Suspension seat

A(8) Time to EAV

Time to ELV

VDVexp Time to shock

of surface time performance criterion (z-axis) (see note

hr:min SEATRMS

SEATVDV m/s² hr:min hr:min m/s1.75

3)

hr:min

Travelling to brick

yard / poor 6:00

0.5

0.5 0.73 02:50 14:58 25.0 (see

note 4) 1:17

Linde FLT

H40D

Loading bricks onto lorry / fair

6:00 0.6

0.6 0.48 06:27 > 24 hrs 13.7 14:01

Travelling back from

brick yard / poor

6:00 0.6

0.5 0.59 04:20 22:56 15.8 08:02

Linde mobile

container handler

Moving containers /

fair 6:00

n/a

n/a 0.42 08:25 > 24 hrs 24.0 (see

note 2) 01:31

Travelling / fair 6:00

`1.4

2.3 0.9 01:51 09:48 34.6 (see

note 2) 00:21

Harbour launch

Cruising around harbour

5:00 (see note 1) No seat 2.67 00:10 00:56 51.9 00:03

Notes

EAV = 0.5 m/s²; ELV = 1.15 m/s²

1. Daily exposure time varies but is usually much less than this

2. Seat damper broken

3. HSE’s criterion indicating account should be taken of shock (VDVexp = 17 m/s1.75)

4. High VDVexp is due to a single shock as driver hit a pothole (this can be seen on the z base time history in Appendix G).

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Table 5. Summary Of Vibration Data – Daily Exposures From Seat Back

Vehicle Task Condition of surface

A(8) (m/s²) VDVexp (m/s1.75)

Seat pan Seat back Seat pan Seat back

Hyster fork lift truck

Moving fertilizer

bags Good 0.45 0.40 11.2 9.6

Komatsu front end

loader

Moving fertilizer Good 0.60 0.48 13.6 12.4

Rail mounted gantry crane

Moving containers n/a 0.12 Not

measured 3.4 Not measured

Kalmar TRX 182

tractor

Loading 6.00pm Ro-

Ro ferry Unknown 0.37 Not


Loading midnight

Ro-Ro ferry Unknown 0.40 Not


Morris rubber

tyred gantry Moving

containers Fair 0.11 Not measured 3.1 Not

measured crane

Travelling to brick

yard Poor 0.73 Not


Linde FLT H40D

Loading bricks onto

lorry Fair 0.48 Not



Poor 0.59 Not measured 15.8 Not

measured

Linde mobile

container handler

Moving containers Fair 0.42 0.33 24.0 * 10.0

Travelling Fair 0.9 0.46 34.6 * 12.8

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Table 6. Summary Of Vibration Data – Spine response method ISO 2631-5

Vehicle Task Condition of surface

Sed R (amber moderate values, red high values)

MPa 20 yr 30 yr 40 yr 50 yr 60 yr 65 yr

Hyster fork lift

truck

Moving fertilizer

bags Good 0.3 0.2 0.3 0.3 0.4 0.5 0.5

Komatsu front end

loader

Moving fertilizer Good 0.6 0.3 0.5 0.6 0.7 0.8 0.9

Rail mounted gantry crane

Moving containers n/a 0.1 0.1 0.1 0.1 0.1 0.2 0.2

Kalmar TRX 182

tractor

Loading 6.00pm Ro-Ro ferry

Unknown 0.8 0.4 0.6 0.7 0.8 1.0 1.2

Loading midnight Ro-Ro ferry

Unknown 0.6 0.3 0.4 0.5 0.6 0.8 0.9

Morris rubber tyred

gantry crane

Moving containers Fair 0.1 0.1 0.1 0.1 0.1 0.2 0.2

Linde FLT

H40D

Travelling to brick

yard Poor 0.7 0.3 0.5 0.6 0.8 0.9 1

Loading bricks

onto lorry Fair 0.5 0.2 0.4 0.5 0.6 0.7 0.8

Travelling from brick

yard Poor 0.6 0.3 0.4 0.5 0.6 0.8 0.9

Linde mobile

container handler

Moving containers Fair 2.0 1.0 1.5 1.9 2.2 2.8 3.1

Travelling Fair 2.4 1.1 1.8 2.2 2.7 3.3 3.7

Harbour launch

Travelling around harbour

Calm 1.6 0.8 1.2 1.5 1.8 2.2 2.5

R < 0.8 low probability of adverse health effect

R > 1.2 high probability of adverse health effect

18

5 DISCUSSION

5.1 CAB ’FIT’

Some weaknesses were found with the cabs, however no major problems were identified. Some drivers appeared to need to lean forward to reach the controls in the cabs, temporarily losing the support of the backrest. In some of the vehicles there was insufficient range of adjustment of the seat height for shorter drivers to be able to sit comfortably. This particularly affects females because of their shorter stature compared to males. Several of the seats were too deep, front to back, to allow some operators to use the backrest effectively.

5.2 POSTURE

The fork lift truck drivers, in particular, needed to twist frequently to reverse their vehicles. This was particularly marked with the Hyster lift truck when manoeuvring the fertilizer bags. A RULA action level of 2 was assigned to this activity indicating, “that further investigation is needed and changes may be required”. Another risk posture identified was for the operators of the gantry cranes. The crane operators need to lean forward and look down through the clear floor of the cab in order to lift and lower containers. The posture they adopted for this was also assigned a RULA action level of 2.

5.3 MANUAL HANDLING

Only one manual handling activity was identified. This was the pallet handling carried out by the Hyster fork lift truck driver, when moving ammonium nitrate bags in the fertilizer store. The activity was scored by the MAC assessment as having some risk associated with it if it was carried out continuously. However the lift truck operator was only required to move pallets occasionally, usually for about 10 minutes at a time.

5.4 VIBRATION EXPOSURES

Under the Control of Vibration at Work Regulations (2005) (CVWR 2005) an employer must assess the risks to its employees from vibration, and if necessary, prepare and implement a plan for their control. For whole-body vibration the Regulations require control of risk and specify an exposure action level (EAV) of 0.5 m/s² A(8) and an exposure limit value (ELV) of 1.15 m/s² A(8). The employees’ daily exposures are compared with the EAV and ELV to determine what further actions are required. The Regulations also advise that shock should be considered. One method of doing this is to estimate the employee’s daily Vibration Dose Value (VDV). An exposure level of 17 m/s1.75 VDV for the working day is considered very high (HSE Guidance on Regulations L141). This is the value of the upper limit of the health guidance caution zone for exposure to whole-body vibration given in ISO 2631:1997.

Looking at the daily vibration exposure estimates in Table 4, the operators of the Hyster fork lift truck, the Morris rail mounted gantry crane, the Kalmar tractor, and the Morris rubber tyred gantry crane were likely exposed below the daily exposure action value of 0.5 m/s² A(8).

The operators of the Komatsu front end loader, and the Linde fork lift truck and Linde mobile container handler were likely exposed between the exposure action value and the limit value in the Regulations.

Most of the daily VDV estimates were below HSE’s guidance figure of 17 m/s1.75. The daily exposure for drivers of the mobile container handler greatly exceeded the guidance figure.

19

However as the damper on the seat of this vehicle was broken, the estimated daily exposures for this vehicle were much higher than they would normally have been.

The performance of the seats on the two fork lift trucks was good, the two seats attenuating both the A(8) and daily VDV exposures. The vibration levels on the two gantry cranes were so low that it would be unreasonable to expect those seats to attenuate the vibration further, and in fact the seats do slightly amplify the exposure of the operators. The seat on the front end loader and that on the tractor unit had little effect on the vibration exposure of the drivers. As mentioned in the previous paragraph the seat in the mobile container handler was broken, and this accounts for the high SEAT values found for that seat.

5.5 SEAT BACK VIBRATION LEVELS

High vibration in the seat back can cause drivers to sit forward, unsupported by the seat back. The A(8) levels on the seat back were comparable to the A(8) levels on the seat pan. The daily VDV estimates on the seat back were similar to the daily VDV estimates for the seat pan.

5.6 SPINE RESPONSE METHOD (ISO 2631-5)

An objective of the next phase (phase 3) of this project is to compare the effect of using different metrics for quantifying whole-body vibration exposure. One relatively new method (sometimes known as the spine response method) of estimating the risk of adverse health effects from exposure to shock is that given in ISO 2631-5:2004. Since phase 3 of the project is not due to be carried out in 2007, and very little data has been analysed to date using this method, the spine response data obtained so far in this project has been collected in Figure 9.

Figure 9 shows a comparison of the VDV and spine response data, for both phase 1 of the project (Darby, 2006) and the results reported here. The VDV data is the daily exposure estimate, and the spine response data is the risk factor at 65 years old assuming that exposure started at the age of 20.

The spine response data tells a broadly similar story to the VDV metric, with very little risk indicated once atypical results have been accounted for.

In most cases vehicles that gave a low risk according to the VDV metric also gave a low risk according to the spine response metric (i.e. they sit in the bottom left hand corner of the graph). Similarly most vehicles that gave a high risk of adverse health effects using the VDV metric also gave a high probability of an adverse health effect by the spine response method (i.e. they sit in the top right hand corner of the graph). In a few cases the spine response and VDV methods gave a different estimate of risk (i.e one high risk, the other low risk). These cases should be looked at in more detail in phase 3 of the project.

20

0

1

2

3

4

0

/s

i li

i l

0.5

1.5

2.5

3.5

10 20 30 40 50

Daily exposure - VDV m 1.75

Spi

ne r

espo

nse

- R a

t age

65

yr

R > 1.2 h gh probabi ty of an adverse health effect

R < 0.8 low probability of an adverse health effect

HSE's guidance f gure for high evel of shock

Figure 9. Comparison of spine response data with daily vibration dose values (phase 1 and phase 2 port data).

21

6 CONCLUSIONS

1. The only noteworthy postural issues found were the frequently adopted reversing posture of the Hyster fork lift truck driver, and the postures adopted by the gantry crane drivers when lifting and lowering containers.

2. No major manual handling issues were observed.

3. Some weaknesses were found with the cabs, however no major problems were identified. Weakness included an inadequate range of seat height adjustment for shorter operators and for several of the seats having too great a seat depth, hindering easy use of the backrest by many of the operators.

4. Operators of the Hyster fork lift truck, the Morris rail mounted gantry crane, the Kalmar tractor, and the Morris rubber tyred gantry crane had likely vibration exposures below the daily exposure action value of 0.5 m/s² A(8) in the Control of Vibration at Work Regulations 2005.

5. The operators of the Komatsu front end loader, and the Linde fork lift truck and Linde mobile container handler were likely exposed between the exposure action value and the limit value in the Regulations.

6. Most of the daily VDV estimates for the vehicles in the study were below HSE’s guidance figure of 17 m/s1.75. The daily exposure for drivers of the mobile container handler greatly exceeded the guidance figure. However as the damper on the seat of this vehicle was broken, the estimated daily exposures for this vehicle were much higher than they would normally have been.

7. The performance of the seats on the two fork lift trucks was good, the two seats attenuating both the A(8) and daily VDV exposures.

8. The seats on the two gantry cranes slightly amplified the exposure of the operators. However the vibration levels from the cranes were so low that it would be unreasonable to expect those seats work properly and to attenuate incident vibration. (A certain level of vibration is needed to overcome friction.)

9. The seat on the front end loader and on the tractor unit had little effect on the vibration exposure of the drivers.

10. The seat in the mobile container handler was broken, and this accounts for the high SEAT values found for that seat.

11. The seat back vibration levels measured were comparable to the highest vibration levels on the seat pan, indicating that seat back vibration data should continue to be gathered, as it may be important when considering adverse health effects.

12. For the data considered here the spine response metric tells a broadly similar story to the VDV metric. In most cases vehicles that gave a low risk according to the VDV metric also gave a low risk according to the spine response metric.

13. Ergonomic factors do not appear to be any more important a source of back pain than whole body vibration in the machines studied here.

22

7 REFERENCES

1. Benchmarking Manual Handling Performance in Welsh Care Homes Marlow P, Pinder A. and Gould V, Health and Safety Laboratory Report ERG/05/20 August 2005

2. Control of Vibration at Work Regulations 2005, ISBN 0110727673, Statutory Instrument 2005 No. 1093

3. Driving Instructors at the Defence School of Transport Leconfield – Whole-body vibration and Ergonomics Assessment. Darby A., Jackson A, and Milne E. Health and Safety Laboratory Report No. NV/02/10. November 2002.

4. ISO 2631-1:1997 Mechanical vibration and shock -- Evaluation of human exposure to whole-body vibration -- Part 1, General requirements

5. ISO 2631-5:2004 Mechanical vibration and shock -- Evaluation of human exposure to whole-body vibration -- Part 5: Method for evaluation of vibration containing multiple shocks

6. Whole-body vibration and ergonomics toolkit – Phase 1. Darby A M, Health and Safety Laboratory Report No. NV/06/14. September 2006

7. Whole-body vibration of ground-preparation activities in forestry. Pitts P, Health and Safety Laboratory Report No. NV/07/09. Draft.

23

APPENDIX A. EQUIPMENT

Item Type

Transducer B&K 4322

Transducer B&K 4322

Transducer B&K 4322

Calibrator B&K 4294

Charge amplifier B&K 2635







Data recorder TEAC RD135T

Analysis system Pulse

Analysis system MatLab

Serial number or

1249795 (w/o nitrile pad)

2010827

1793200

1121535

2448012

2448013

2448014

1625036

1493485

1473733

1493484

723517

2325758

Program vdv2_5

Section ID Calibration due

445 August 2007

674 August 2007

November 2007

November 2007

July 2007

July 2007

July 2007

January 2008

January 2008

January 2007

November 2007

June 2007

24

APPENDIX B. HYSTER FORK LIFT TRUCK

Photograph B.1 Hyster fork lift truck moving fertilizer bags

Photograph B.2 Hyster fork lift truck seat

25

Vibration data (without k factor) Site/meas. no. Site 1_veh1 Vehicle: Hyster FLT H5.50XM Measurement date: 21/11/2006 Seat: Mechanical suspension Tape/ID no: 2/1

Analysis length : 1170 seconds Task: Simulated loading / unloading of Freq. increment: 0.125 Hz fertiliser bags onto lorry

Seat Seat base Seat back x y z x y z x

RMS (m/s²) (Unweighted) 0.96 0.98 0.67 1.02 0.88 1.34 1.44

RMS (m/s²) (ISO 2631-1:1997) 0.37 0.28 0.48 0.36 0.22 0.60 0.58

VDV (m/s1.75) (ISO 2631-1:1997)

3.39 2.64 5.40 3.29 2.22 6.72 5.81

eVDV (m/s1.75) (ISO 2631-1:1997)

3.02 2.29 3.94 2.92 1.79 4.88 4.76

Crest factor (ISO 2631-1:1997) 8 7 12 7 12 11 8

MTVV linear (m/s²) (ISO 2631:1997) 1.23 1.18 2.39 1.24 1.12 3.06 2.59

MTVV exp. (m/s²) (ISO 2631:1997) 1.13 1.01 2.09 1.13 0.92 2.69 2.19

SEAT factor (RMS) 1.0 1.3 0.8

SEAT factor (VDV) 1.0 1.2 0.8

Exposure duration: 06:00:00 Seat back contact time (%) : 100

A(8) value for comparison with the exposure action (0.5 m/s² A(8)) and limit (1.15 m/s² A(8)) values in the Control of Vibration at Work Regulations 2005

A(8) (m/s²) 0.45 (x direction) Time to action value 07:31:18

Time to limit value > 24 hrs

VDV for comparison with HSE's criterion for significance of shock

VDVexp (m/s1.75) 11.2 (z direction) Time to 17 m/s1.75 > 24 hrs

Spine response data for comparison with the criterion set out in ISO 2631-5:2004, R < 0.8 low probability of an adverse health effect, R > 1.2 high probability of an adverse health effect

Dx Dy Dz Sed (m/s2) (m/s2) (m/s2) (MPa)

6.6 5.6 5.0 0.3

R Age (yrs)

20 30 40 50 60 65 0.2 0.3 0.3 0.4 0.5 0.5

26

27

Site/meas. no. Site 1_veh1Measurement date: 21/11/2006Tape/ID no: 2/1

Vehicle: Hyster FLT H5.50XMSeat: Mechanical suspension

Freq. increment: 0.125 Hz

0.001

0.01

0.1

1

0.1 1 10 100Frequency (Hz)

Acc

. PS

D (m

/s²)²

/Hz

. x seat back

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce

x frequencyresponsex coherence

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce

y frequencyresponsey coherence

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce

z frequencyresponsez coherence

28

Site/meas. no. Site 1_veh1 Vehicle: Hyster FLT H5.50XM

x-axis: time (minutes) y-axis (left): unweighted accel. (m/s²) y-axis (right): cumulative VDV (m/s1.75)

x seat

-5

0

5

0 2 4 6 8 10 12 14 16 18

0

5

10

y seat

-5

0

5

0 2 4 6 8 10 12 14 16 180

5

10

z seat

-5

0

5

0 2 4 6 8 10 12 14 16 180

5

10

x base

-5

0

5

0 2 4 6 8 10 12 14 16 180

5

10

y base

-5

0

5

0 2 4 6 8 10 12 14 16 18

0

5

10

z base

-5

0

5

0 2 4 6 8 10 12 14 16 180

5

10

x back

-5

0

5

0 2 4 6 8 10 12 14 16 180

5

10

Site/meas. no. Site 1_veh1 Vehicle: Hyster FLT H5.50XM

-1

0

1

0 2 4 6 8

Ti (

1 =

cont

act,

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

10 12 14 16 18

me minutes)

0 =

no c

onta

ct

Manual handling activities Driver needs to move pallets in ammonium nitrate store when placing fertilizer bags in store or removing them from the store. Maximum continuous length of time spent moving pallets is approximately 10 minutes. (Pallets are moved occasionally.) Moving the pallets scores greens and ambers for all elements of the task, except for the vertical lift region which scores red.

Cab ‘fit’assessment

WBV Anthropometric Design Assessments v4

Body dimensions taken from PeopleSize 2000 Professional Version 2.05

Project number: JR45083 - phase 2 Site: 1

Date of measurements: 21/11/2006 Vehicle: 1 - Hyster 5.50 counterbalance lift truck

British Adult Male British Adult Female Min. or Fixed Max Min Max Min. or

Fixed Max Min Max

Pedals

Knee angle 135 ° 95 ° 160 ° 140 ° 135 ° 95 ° 160 ° 140 °

H-point vertical height 430 470 430 470 430 470 430 470 Projection of H-point to heel point (horizontal) 610 750 610 750 610 750 610 750

For light pedal force ( < 100N ) male drivers above and female drivers above

91 99

percentile percentile may not have sufficient leg room to adopt a comfortable knee angle For light pedal force,

there is sufficient leg room for most drivers.

For strong pedal force ( > 100N ) male drivers above 1 percentile and female drivers above 2 percentile may not have sufficient leg room to adopt a knee angle in the optimum range

29

430 0

470 0 0

490 0 0

390 0 0

460 0 0

610 0 0

0 200 0

800

950 0 0

430

Seat

Seat pan height at front (Dimension used: popliteal height)

Male drivers above 17 percentile Most male drivers, (but few and female drivers above 76 percentile should be able to place their feet on the floor while seated female drivers) should be

able to place their feet on Seat pan depth (front to back) 470 the floor while seated

(Dimension used: buttock to popliteal)

Male drivers below 13 percentile Some drivers will find the and female drivers below 32 percentile may find the seat pan too deep (front to back) seat pan too deep

Seat pan width 490 (Dimension used: hip breadth)

Male drivers above 99 percentile The seat pan will be wide and female drivers above 98 percentile may find the seat pan too narrow enough for most drivers

Back rest height 390 (Dimension used: sitting shoulder height)

Male drivers above 1 percentile Most drivers will have a and female drivers above 1 percentile will have a greater shoulder sitting height than the seat back shoulder sitting height

greater than the seat back Back rest width 460 height

(Dimension used: chest breath at nipple)

Male drivers above 99 percentile Back rest is wide enough and female drivers above 99 percentile will find the seat back too narrow for most drivers

l 610

Steering

Top of seat back to top of steering whee(Dimension used: forward grip reach)Percentile 1 1

At the limits of adjustment males below 1 percentile, and females below 1 percentile may have difficulty reaching the far edge of the steering wheel

Seat pan to steering wheel (vertical) 200 (Dimension used: thigh depth)

With the seat at lowest height setting male drivers above 94 percentile may not have sufficient thigh clearance and female drivers above 95 percentile may not have sufficient thigh clearance

800

Gear Lever

Top left of seat back to top of gear lever

Most drivers will be able to reach the far edge of the steering wheel

There is sufficient clearance between the seat pan and steering wheel for most drivers

(Dimension used: forward grip reach)

Male drivers below 94 percentile Control is outside the reach and female drivers below 99 percentile may have difficulty reaching the gear lever from a neutral posture zone from a neutral posture

for most drivers

950

Hand Brake

Top left of seat back to front of hand brake (Dimension used: forward grip reach)

Control is outside the reach and female drivers below 99 percentile may have difficulty reaching the hand brake from a neutral posture Male drivers below 99 percentile

zone from a neutral posture for most drivers

Posture assessment Frequent reversing involved in task - Rula action level of 2 for this activity

30

APPENDIX C. KOMATSU FRONT END LOADER

Photograph C.1 Komatsu front end loader

Photographs C.2 Komatsu front end loader moving fertilizer and C.3 Komatsu seat.

31

Vibration data (without k factor) Site/meas. no. Site 1_veh2 Vehicle: Komatsu front end loader Measurement date: 21/11/2006 Seat: ISRI 6500 mechanical suspension Tape/ID no: 2/2

Analysis length : 670 seconds Task: Moving fertiliser Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) 0.80 0.70 0.60 - 0.64 0.51 0.91

RMS (m/s²) (ISO 2631-1:1997) 0.48 0.49 0.36 - 0.41 0.34 0.69

VDV (m/s1.75) (ISO 2631-1:1997)

4.06 4.07 2.94 - 3.41 3.16 6.52

eVDV (m/s1.75) (ISO 2631-1:1997)

3.45 3.52 2.56 - 2.92 2.40 4.91

Crest factor (ISO 2631-1:1997) 6 6 14 - 8 11 8

MTVV linear (m/s²) (ISO 2631:1997) 1.82 2.09 1.23 - 1.79 1.12 2.72

MTVV exp. (m/s²) (ISO 2631:1997) 1.56 1.88 1.14 - 1.65 0.97 2.40

SEAT factor (RMS) - 1.2 1.1

SEAT factor (VDV) - 1.2 0.9



A(8) (m/s²) 0.6 (y direction) Time to action value 04:10:30

Time to limit value 22:05:10


VDVexp (m/s1.75) 13.6 (y direction) Time to 17 m/s1.75 14:46:40



8.9 9.4 4.9 0.6

R Age (yrs)

20 30 40 50 60 65 0.3 0.5 0.6 0.7 0.8 0.9

32

33


Vehicle: Komatsu front end loaderSeat:


ISRI 6500 mechanical suspension

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat back

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


34

Site/meas. no. Site 1_veh2 Vehicle: Komatsu front end loader


x seat

-5

0

5

0 2 4 6 8 10

0

5

10

y seat

-5

0

5

0 2 4 6 8 100

5

10

z seat

-5

0

5

0 2 4 6 8 100

5

10

y base

-5

0

5

0 2 4 6 8 10

0

5

10

z base

-5

0

5

0 2 4 6 8 100

5

10

x back

-5

0

5

0 2 4 6 8 100

5

10

Site/meas. no. Site 1_veh2 Vehicle: Komatsu front end loader

-1

0

1

0 2 4 6 8

Ti (

1 =

cont

act,

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

10

me minutes)

0 =

no c

onta

ct

Manual handling activities None found.

Cab ‘fit’ assessment




Date of measurements: 21/11/2006 Vehicle: 2 - Komatsu WA380 Front end loader


Fixed Max Min Max

Pedals

Knee angle 135 ° 95 ° 160 ° 140 ° 135 ° 95 ° 160 ° 140 °



99 99

percentile percentile may not have sufficient leg room to adopt a comfortable knee angle For light pedal force

there is sufficient leg room for most drivers


35

400 0

480 0 0

480 0 0

480 0 0

470 0 0

0685 0 0

650 0 0

0 210 0

550

400

Seat


Male drivers above and female drivers above

Seat pan depth (front to back) (Dimension used: buttock to popliteal)

Male drivers below and female drivers below

Seat pan width (Dimension used: hip breadth)


Back rest height (Dimension used: sitting shoulder height)


Back rest width (Dimension used: chest breath at nipple)


Head rest height Sitting height


Top of seat back to top of steering wheel (Dimension used: forward grip reach)

At the limits of adjustment males below

1 percentile 31 percentile should be able to place their feet on the floor while seated

480

22 percentile 45 percentile may find the seat pan too deep (front to back)

480

99 percentile 97 percentile may find the seat pan too narrow

480

1 percentile 1 percentile will have a greater shoulder sitting height than the seat back

470

99 percentile 99 percentile will find the seat back too narrow

205 685

1 percentile 1 percentile will find the head rest height too low

Most drivers will be able to place their feet on the floor while seated

Some drivers will find the seat pan too deep

The seat pan will be wide enough for most drivers

Most drivers will have a shoulder sitting height greater than the seat back height

Back rest is wide enough for most drivers

Most drivers will find the head rest height too low

Most drivers will be able to reach the far edge of the steering wheel


Controls are within reach from a neutral posture for most drivers

650

Steering

may have difficulty reaching the far edge of the steering wheel



550

Gear Lever


1 percentile, and females below 7 percentile


Male drivers below 1 percentile and female drivers below 1 percentile may have difficulty reaching the gear lever from a neutral posture

Posture assessment No major problems identified.

36

APPENDIX D. MORRIS RAIL MOUNTED GANTRY CRANE

Photograph D.1 Morris rail mounted gantry crane

Photographs D.2 and D.3 Morris rail mounted gantry crane cab (access by ladder)

37

Vibration data (without k factor) Site/meas. no. Site 1_veh3 Vehicle: Morris 35.6t rail mounted gantry crane Measurement date: 21/11/2006 Seat: Mechanical suspension, KAB 303 Tape/ID no: 3/1

Analysis length : 1860 seconds Task: Moving containers Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) - 0.25 0.29 0.25 0.36 0.20 -

RMS (m/s²) (ISO 2631-1:1997) - 0.08 0.17 0.05 0.10 0.14 -

VDV (m/s1.75) (ISO 2631-1:1997) - 1.00 2.03 0.88 1.94 1.81 -

eVDV (m/s1.75) (ISO 2631-1:1997) - 0.76 1.59 0.47 0.93 1.30 -

Crest factor (ISO 2631-1:1997) - 10 13 20 24 13 -

MTVV linear (m/s²) (ISO 2631:1997) - 0.47 1.27 0.69 1.52 1.15 -

MTVV exp. (m/s²) (ISO 2631:1997) - 0.40 1.05 0.55 1.23 0.94 -



Exposure duration: 04:00:00 Seat back contact time (%) : Not measured


A(8) (m/s²) 0.12 (z direction) Time to action value > 24 hrs



m/s1.75VDVexp ( ) 3.4 (z direction) Time to 17 m/s1.75 > 24 hrs



- 2.3 2.6 0.1

R Age (yrs)

20 30 40 50 60 65 0.1 0.1 0.1 0.1 0.2 0.2

38

39


Vehicle: Morris 35.6t rail mounted gantry craneSeat: Mechanical suspension, KAB 303


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat base

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


40

Site/meas. no. Site 1_veh3 Vehicle: Morris 35.6t rail mounted gantry crane


y seat

-5

0

5

0 5 10 15 20 25 300

5

10

z seat

-5

0

5

0 5 10 15 20 25 300

5

10

x base

-5

0

5

0 5 10 15 20 25 300

5

10

y base

-5

0

5

0 5 10 15 20 25 300

5

10

z base

-5

0

5

0 5 10 15 20 25 300

5

10


490 0 0

450 0 0

550 0 0

420 0 0

600





Date of measurements: 21/11/2006 Vehicle: 3 - Morris rail mounted gantry crane

British Adult Male British Adult Female Findings Min. or Fixed Max Min. or

Fixed Max

There are no foot controls. There is ample leg room for all drivers

(Dimension used: buttock to popliteal)









(Dimension used: forward grip reach) Controls are within reach

Male drivers below 1 percentile from a neutral posture for and female drivers below 1 percentile may have difficulty reaching the gear lever from a neutral posture most drivers

Posture assessment Picking up and putting down containers – RULA action level of 2.

) 490

Seat

Seat pan depth (front to back

600

Gear Lever


41

APPENDIX E. KALMAR TRX 182 TRACTOR

Photograph E.1 Kalmar TRX 182 tractor

Photographs E.2 and E.3 Kalmar TRX 182 tractor cab

42

Vibration data (without k factor) - 6.00pm ferry Site/meas. no. Site 1_veh4 Vehicle: Kalmar TRX 182 tractor (No. 9) Measurement date: 21/11/2006 Seat: Kab, air suspension Tape/ID no: 4/1

Analysis length : 155 seconds Task: Loading of 6.00pm Ro-Ro Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) 0.65 0.84 0.79 0.61 0.80 0.67 -

RMS (m/s²) (ISO 2631-1:1997) 0.33 0.34 0.44 0.27 0.33 0.35 -

VDV (m/s1.75) (ISO 2631-1:1997)

2.22 2.45 3.81 1.87 2.30 2.95 -

eVDV (m/s1.75) (ISO 2631-1:1997)

1.65 1.66 2.19 1.32 1.61 1.75 -

Crest factor (ISO 2631-1:1997) 7 10 12 8 9 18 -

MTVV linear (m/s²) (ISO 2631:1997) 1.54 1.44 1.95 1.14 1.62 1.54 -

MTVV exp. (m/s²) (ISO 2631:1997) 1.28 1.33 1.67 0.93 1.43 1.38 -





A(8) (m/s²) 0.37 (y direction) Time to action value 09:02:08



VDVexp (m/s1.75) 12.5 (z direction) Time to 17 m/s1.75 17:05:14



5.8 5.7 10.5 0.8

R Age (yrs)

20 30 40 50 60 65 0.4 0.6 0.7 0.8 1 1.2

43

44


Vehicle: Kalmar TRX 182 tractor (No. 9)Seat: Kab, air suspension


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


45

Site/meas. no. Site 1_veh4 Vehicle: Kalmar TRX 182 tractor (No. 9)


x seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

y seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

z seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

x base

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

y base

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

z base

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

Vibration data (without k factor)- Midnight ferry Site/meas. no. Site 1_veh4b Vehicle: Kalmar TRX 182 tractor (No. 9) Measurement date: 22/11/2006 Seat: Kab, air suspension Tape/ID no: 4/1

Analysis length : 780 seconds Task: Loading midnight Ro-Ro Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) 0.61 0.69 0.63 0.57 0.73 0.65 -

RMS (m/s²) (ISO 2631-1:1997) 0.36 0.34 0.34 0.34 0.28 0.40 -

VDV (m/s1.75) (ISO 2631-1:1997)

3.62 3.47 4.18 3.90 2.68 4.17 -

eVDV (m/s1.75) (ISO 2631-1:1997)

2.67 2.54 2.52 2.51 2.07 2.94 -

Crest factor (ISO 2631-1:1997) 11 10 11 14 8 17 -

MTVV linear (m/s²) (ISO 2631:1997) 1.73 1.87 2.20 2.37 1.47 1.80 -

MTVV exp. (m/s²) (ISO 2631:1997) 1.65 1.57 1.91 1.97 1.34 1.62 -








VDVexp (m/s1.75) 11.1 (x direction) Time to 17 m/s1.75 > 24 hrs



9.4 6.9 10.0 0.6

R Age (yrs)

20 30 40 50 60 65 0.3 0.4 0.5 0.6 0.8 0.9

46

47

Site/meas. no. Site 1_veh4bMeasurement date: 22/11/2006Tape/ID no: 4/1

Vehicle: Kalmar TRX 182 tractor (No. 9)Seat: Kab, air suspension


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


48

Site/meas. no. Site 1_veh4b Vehicle: Kalmar TRX 182 tractor (No. 9)


x seat

-5

0

5

0 2 4 6 8 10 12

0

5

10

y seat

-5

0

5

0 2 4 6 8 10 12

0

5

10

z seat

-5

0

5

0 2 4 6 8 10 12

0

5

10

x base

-5

0

5

0 2 4 6 8 10 12

0

5

10

y base

-5-3-1135

0 2 4 6 8 10 12

0246810

z base

-5

0

5

0 2 4 6 8 10 12

0

5

10


500 0 0

495 0 0

500 0 0

490 0 0

740 0 0

0 200 0





Date of measurements: 22/11/2006 Vehicle: 4 - Kalmar TRX 182 tractor


Fixed Max Min Max

Pedals

Knee angle 135 ° 95 ° 160 ° 140 ° 135 ° 95 ° 160 ° 140 °

H-point vertical height 540 540 540 540 540 540 540 540 Projection of H-point to heel point (horizontal) 500 900 500 900 500 900 500 900 Accommodated hip to ankle distance 772 1399 722 1092 772 1399 722 1092

For light pedal force ( < 100N ) male drivers above 99 percentile and female drivers above 99 percentile may not have sufficient leg room to adopt a comfortable knee angle


For light pedal force, there is sufficient leg room for most drivers.

) 500

Seat

Seat pan depth (front to back(Dimension used: buttock to popliteal)





Male drivers above 1 percentile Most drivers will have a and female drivers above 1 percentile will have a shoulder sitting height above the seat back shoulder sitting height




740

Steering





Posture assessment No assessment made.

Some drivers will have difficulty reaching the far edge of the steering wheel from a neutral posture


49

APPENDIX F. RUBBER TYRED GANTRY CRANE

Photograph F.1 Rubber tyre gantry crane (access by ladder)

50

Vibration data (without k factor) Site/meas. no. Site 1_veh5 Vehicle: Rubber tyred gantry crane Measurement date: 22/11/2006 Seat: Unidentified manufacturer, suspension Tape/ID no: 4/3



RMS (m/s²) (Unweighted) 0.20 0.26 0.12 0.23 - 0.12 -

RMS (m/s²) (ISO 2631-1:1997) 0.11 0.12 0.07 0.10 - 0.06 -

VDV (m/s1.75) (ISO 2631-1:1997)

1.11 1.16 0.79 0.89 - 0.65 -

eVDV (m/s1.75) (ISO 2631-1:1997)

0.89 0.92 0.59 0.76 - 0.46 -

Crest factor (ISO 2631-1:1997) 8 8 12 7 - 15 -

MTVV linear (m/s²) (ISO 2631:1997) 0.70 0.48 0.52 0.34 - 0.38 -

MTVV exp. (m/s²) (ISO 2631:1997) 0.57 0.42 0.43 0.29 - 0.30 -

SEAT factor (RMS) 1.2 - 1.3

SEAT factor (VDV) 1.2 - 1.2



A(8) (m/s²) 0.11 (y direction) Time to action value > 24 hrs



VDVexp (m/s1.75) 3.1 (y direction) Time to 17 m/s1.75 > 24 hrs



2.1 2.0 1.2 0.1

R Age (yrs)

20 30 40 50 60 65 0.1 0.1 0.1 0.1 0.2 0.2

51

52


Vehicle: Rubber tyred gantry craneSeat: Unidentified manufacturer, suspension


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. y seat

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


53

Site/meas. no. Site 1_veh5 Vehicle: Rubber tyred gantry crane


x seat

-5

0

5

0 2 4 6 8 10 12 14 16

0

5

10

y seat

-5

0

5

0 2 4 6 8 10 12 14 160

5

10

z seat

-5

0

5

0 2 4 6 8 10 12 14 160

5

10

x base

-5

0

5

0 2 4 6 8 10 12 14 160

5

10

z base

-5

0

5

0 2 4 6 8 10 12 14 160

5

10

Manual handling activities None found. Cab ‘fit’ Identical to vehicle 3. Posture assessment As vehicle 3. Picking up and putting down containers – RULA action level of 2.

APPENDIX G. LINDE FORK LIFT TRUCK

Photograph G.1 Linde Fork Lift Truck

Photograph G.2 Linde Fork Lift Truck Cab

54

Vibration data (without k factor) - travelling to brick yard Site/meas. no. Ip_veh6 Vehicle: Lansing Linde FLT H40D Measurement date: 22/11/2006 Seat: Grammer, mechanical suspension Tape/ID no: 4/7

Analysis length : 300 seconds Task: Travelling to brick yard over poor surface Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) 1.04 1.06 0.99 - 1.24 1.95 -

RMS (m/s²) (ISO 2631-1:1997) 0.41 0.47 0.84 - 0.42 1.58 -

VDV (m/s1.75) (ISO 2631-1:1997)

3.23 3.81 8.59 - 3.41 16.51 -

eVDV (m/s1.75) (ISO 2631-1:1997)

2.41 2.73 4.90 - 2.45 9.22 -

Crest factor (ISO 2631-1:1997) 10 11 10 - 9 15 -

MTVV linear (m/s²) (ISO 2631:1997) 2.04 1.95 5.39 - 1.88 10.60 -

MTVV exp. (m/s²) (ISO 2631:1997) 1.79 1.81 4.62 - 1.66 9.25 -





A(8) (m/s²) 0.73 (z direction) Time to action value 02:49:39






5.8 9.0 8.1 0.7

R Age (yrs)

20 30 40 50 60 65 0.3 0.5 0.6 0.8 0.9 1

55

56

Site/meas. no. Ip_veh6Measurement date: 22/11/2006Tape/ID no: 4/7

Vehicle: Lansing Linde FLT H40DSeat: Grammer, mechanical suspension


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


57

Site/meas. no. Ip_veh6 Vehicle: Lansing Linde FLT H40D


x seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 50

10

20

y seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 50

10

20

z seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 50

10

20

y base

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 50

10

20

z base

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 50

10

20


-1

0

1

0 1 2 3 4 5

(mi )

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

0.5 1.5 2.5 3.5 4.5

Time nutes

1 =

cont

act,

0 =

no

cont

act

58

Vibration data (without k factor) - loading lorry with bricks Site/meas. no. Ip_veh6 Vehicle: Lansing Linde FLT H40D Measurement date: 22/11/2006 Seat: Grammer, mechanical suspension Tape/ID no: 4/7

Analysis length : 1080 seconds Task: Moving bricks Freq. increment: 0.125 Hz



RMS (m/s²) (ISO 2631-1:1997) 0.40 0.36 0.49 - 0.32 0.80 -

VDV (m/s1.75) (ISO 2631-1:1997)

3.52 3.85 6.50 - 3.40 11.84 -

eVDV (m/s1.75) (ISO 2631-1:1997)

3.19 2.85 3.95 - 2.59 6.40 -

Crest factor (ISO 2631-1:1997) 6 10 12 - 9 14 -


MTVV exp. (m/s²) (ISO 2631:1997) 1.19 1.40 2.55 - 1.24 5.09 -











6.1 8.3 7.0 0.5

R Age (yrs)

20 30 40 50 60 65 0.2 0.4 0.5 0.6 0.7 0.8

59

60




0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


61



x seat

-5

0

5

0 2 4 6 8 10 12 14 16 180

10

20

y seat

-5

0

5

0 2 4 6 8 10 12 14 16 180

10

20

z seat

-5

0

5

0 2 4 6 8 10 12 14 16 180

10

20

y base

-5

0

5

0 2 4 6 8 10 12 14 16 180

10

20

z base

-5

0

5

0 2 4 6 8 10 12 14 16 180

10

20


-1

0

1

5 7 9 11 13 15

Ti (

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

17

me minutes)

1 =

cont

act,

0 =

no

cont

act

62

Vibration data (without k factor) - travelling back from brick yard Site/meas. no. Ip_veh6 Vehicle: Lansing Linde FLT H40D Measurement date: 22/11/2006 Seat: Grammer, mechanical suspension Tape/ID no: 4/7

Analysis length : 150 seconds Task: Returning from brick yard over poor surface Freq. increment: 0.125 Hz



RMS (m/s²) (ISO 2631-1:1997) 0.47 0.47 0.68 - 0.43 1.15 -

VDV (m/s1.75) (ISO 2631-1:1997)

2.42 2.91 4.56 - 2.57 8.48 -

eVDV (m/s1.75) (ISO 2631-1:1997)

2.29 2.30 3.33 - 2.08 5.66 -

Crest factor (ISO 2631-1:1997) 5 8 9 - 7 8 -


MTVV exp. (m/s²) (ISO 2631:1997) 1.19 1.40 2.12 - 1.24 3.89 -











5.1 6.8 5.3 0.6

R Age (yrs)

20 30 40 50 60 65 0.3 0.4 0.5 0.6 0.8 0.9

63

64




0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


65



x seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

y seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

z seat

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

y base

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10

z base

-5

0

5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20

5

10


-1

0

1

19 20

Ti (

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

18 18.5 19.5 20.5

me minutes)

1 =

cont

act,

0 =

no

cont

act


Cab ‘fit’assessment




Date of measurements: 22/11/2006 Vehicle: 6 - Lansing Linde FLT H40D


Fixed Max Min Max

Pedals

Knee angle 135 ° 95 ° 160 ° 140 ° 135 ° 95 ° 160 ° 140 °



94 99

percentile percentile may not have sufficient leg room to adopt a comfortable knee angle For light pedal force,

there is sufficient leg room for most drivers.


66

420 0

425 0 0

430 0 0

450 0 0

415 0 0

725 0 0

0 220 0

530

530 0 0

420

Seat


Male drivers above 8 percentile Most drivers should be able and female drivers above 62 percentile should be able to place their feet on the floor while seated to place their feet on the

floor while seated

Seat pan depth (front to back) 425 (Dimension used: buttock to popliteal)

Male drivers below 1 percentile Very few drivers will find the and female drivers below 2 percentile may find the seat pan too deep (front to back) seat pan too deep








l 725

Steering

Top of seat back to top of steering whee(Dimension used: forward grip reach)Percentile 36 71



With the seat at lowest height setting male drivers above 99 percentile may not have sufficient thigh clearance and all female drivers will have sufficient thigh clearance available

530

Gear Lever

Top right of seat back to top of gear lever

Some drivers will have difficulty reaching the far edge of the steering wheel




1 1

percentile percentile may have difficulty reaching the gear lever from a neutral posture

Control is within the reach zone from a neutral posture for most drivers

530

Hand Brake

Top right of seat back to front of hand brake (Dimension used: forward grip reach)


1 1

percentile percentile may have difficulty reaching the hand brake from a neutral posture


Posture assessment Video not good enough for RULA assessment to be made. May be some problems twisting when reversing, but no major problems identified.

67

APPENDIX H. LINDE MOBILE CONTAINER HANDLER

Photograph H.1 Linde Mobile Container Handler

Photograph H.2 Linde Mobile Container Handler Cab

68

Vibration data (without k factor) - measurements without channel 6 Site/meas. no. Site 1_veh7 Vehicle: Linde mobile container handler C4531CH Measurement date: 22/11/2006 Seat: Kab, mechanical suspension Tape/ID no: 5/2



RMS (m/s²) (Unweighted) 0.38 0.42 0.66 0.43 1.01 - 0.76

RMS (m/s²) (ISO 2631-1:1997) 0.23 0.16 0.49 0.14 0.17 - 0.48

VDV (m/s1.75) (ISO 2631-1:1997)

3.41 1.90 13.08 1.65 1.83 - 6.81

eVDV (m/s1.75) (ISO 2631-1:1997)

2.16 1.49 4.52 1.32 1.59 - 4.41

Crest factor (ISO 2631-1:1997) 14 15 60 13 9 - 20

MTVV linear (m/s²) (ISO 2631:1997) 2.19 0.93 7.17 0.81 0.90 - 3.50

MTVV exp. (m/s²) (ISO 2631:1997) 1.91 0.81 6.34 0.66 0.87 - 3.08

SEAT factor (RMS) 1.6 0.9 -

SEAT factor (VDV) 2.1 1.0 -








Dx Dy Dz Sed (m/s2) (m/s2) (m/s2) (MPa) 10.5 3.8 41.5 2.0

R Age (yrs)

20 30 40 50 60 65 1 1.5 1.9 2.2 2.8 3.1

69

70


Vehicle: Linde mobile container handler C4531CHSeat: Kab, mechanical suspension


0.001

0.01

0.1

1


Acc.

PS

D (m

/s²)²

/Hz

. x seat back

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. z seat

71

Site/meas. no. Site 1_veh7 Vehicle: Linde mobile container handler C4531CH


x seat

-10-505

10

0 5 10 15 20 25 30

05101520

y seat

-10-505

10

0 5 10 15 20 25 3005101520

z seat

-10-505

10

0 5 10 15 20 25 3005101520

x base

-10-505

10

0 5 10 15 20 25 3005101520

y base

-10-505

10

0 5 10 15 20 25 30

05101520

x back

-10-505

10

0 5 10 15 20 25 3005101520

Site/meas. no. Site 1_veh7 Vehicle: Linde mobile container handler C4531CH

-1

0

1

0 5 10 15 20 25 30

Ti (

1 =

cont

act,

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

me minutes)

0 =

no c

onta

ct

72

Vibration data (without k factor) - measurements with channel 6 Site/meas. no. Ip_veh7 with ch 6 Vehicle: Linde mobile container handler C4531CH Measurement date: 22/11/2006 Seat: Kab, mechanical suspension Tape/ID no: 5/1

Analysis length : 270 seconds Task: Travelling Freq. increment: 0.125 Hz


RMS (m/s²) (Unweighted) 0.68 0.75 1.40 0.65 1.24 1.19 0.79

RMS (m/s²) (ISO 2631-1:1997) 0.44 0.29 1.04 0.18 0.25 0.74 0.67

VDV (m/s1.75) (ISO 2631-1:1997) 3.06 1.69 11.57 1.11 1.35 5.12 5.36

eVDV (m/s1.75) (ISO 2631-1:1997) 2.52 1.64 5.90 1.04 1.40 4.20 3.82

Crest factor (ISO 2631-1:1997) 5 7 23 7 4 16 14

MTVV linear (m/s²) (ISO 2631:1997) 1.72 0.76 5.70 0.67 0.54 2.79 3.14

MTVV exp. (m/s²) (ISO 2631:1997) 1.57 0.68 5.09 0.57 0.45 2.33 2.88



Exposure duration: 06:00:00 Seat back contact time (%) : 99.9





m/s1.75VDVexp ( ) 34.6 (z direction) Time to 17 m/s1.75 00:21:00



9.0 3.7 35.8 2.4

R Age (yrs)

20 30 40 50 60 65 1.1 1.8 2.2 2.7 3.3 3.7

73

74

Site/meas. no. Ip_veh7 with ch 6Measurement date: 22/11/2006Tape/ID no: 5/1

Vehicle: Linde mobile container handler C4531CHSeat: Kab, mechanical suspension


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

. x seat back

0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

x seatx seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.001

0.01

0.1

1


Acc

. PS

D (m

/s²)²

/Hz

.

y seaty seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


0.01

0.1

1

10


Acc

. PS

D (m

/s²)²

/Hz

.

z seatz seat base

0.1

1

10


Mag

nitu

de .

0

0.5

1

Coh

eren

ce


75

Site/meas. no. Ip_veh7 with ch 6 Vehicle: Linde mobile container handler C4531CH


x seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

y seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

z seat

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

x base

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

y base

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

z base

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

x back

-5

0

5

0 0.5 1 1.5 2 2.5 3 3.5 405101520

Site/meas. no. Ip_veh7 with ch 6 Vehicle: Linde mobile container handler C4531CH

-1

0

1

0 1 1.5 2 2.5 3 4

Ti

1 =

cont

act,

Seat back contact

-1.25

-0.75

-0.5

-0.25

0.25

0.5

0.75

1.25

0.5 3.5

me (minutes)

0 =

no c

onta

ct






Date of measurements: 22/11/2006 Vehicle: 7 - Linde mobile container handler C4531CH


Fixed Max Min Max

Pedals

Knee angle 135 ° 95 ° 160 ° 140 ° 135 ° 95 ° 160 ° 140 °


For light pedal force ( < 100N ) male drivers above 99 percentile and female drivers above 99 percentile may not have sufficient leg room to adopt a comfortable knee angle

There is sufficient leg For strong pedal force ( > 100N ) room for most drivers

male drivers above 84 percentile and female drivers above 98 percentile may not have sufficient leg room to adopt a knee angle in the optimum range

76

440 0

490 0 0

470 0 0

620 0 0

400 0 0

770 0 0

0 180 0

60 0 0

440

Seat


Male drivers above 28 percentile and female drivers above 86 percentile should be able to place their feet on the floor while seated

Seat pan depth (front to back) 490 (Dimension used: buttock to popliteal)

Male drivers below 33 percentile and female drivers below 57 percentile may find the seat pan too deep (front to back)


Male drivers above 99 percentile and female drivers above 94 percentile may find the seat pan too narrow


Male drivers above 30 percentile and female drivers above 92 percentile will have a greater shoulder sitting height than the seat back

Back rest width 400 (Dimension used: chest breath at nipple)

Male drivers above 99 percentile and female drivers above 99 percentile will find the seat back too narrow

770

Steering





Hand Brake

60 Top left of seat back to front of hand brake (Dimension used: forward grip reach)

Male drivers below 1 percentile and female drivers below 1 percentile may have difficulty reaching the hand brake from a neutral posture

Posture assessment

Most drivers should be able to place their feet on the floor while seated

Some drivers will find the seat pan too deep

The seat pan will be wide enough for most drivers

Many drivers will have a shoulder sitting height greater than the seat back height

Back rest is wide enough for most drivers

Many drivers will have difficulty reaching the far edge of the steering wheel from a neutral position



Video not good enough for RULA assessment to be made, but no major problems apparent.

77

APPENDIX I. HARBOUR LAUNCH

Photograph I.1 Harbour launch

Photograph I.2 Measurement set-up

78

Vibration data (without k factor) Site/meas. no. Ip_veh8 Vehicle: Harbour launch Measurement date: 22/11/2006 Seat: None, vibration measured on deck at Tape/ID no: 4/5 operator's feet

Analysis length : 200 seconds Task: Travelling around harbour (calm conditions) Freq. increment: 0.125 Hz

x y z RMS (m/s²) (Unweighted) 1.53 0.89 18.33

RMS (m/s²) (ISO 2631-1:1997) 0.07 0.05 3.38

VDV (m/s1.75) (ISO 2631-1:1997)

0.30 0.27 16.85

eVDV (m/s1.75) (ISO 2631-1:1997)

0.36 0.28 17.77

Crest factor (ISO 2631-1:1997) 3 5 6

MTVV linear (m/s²) (ISO 2631:1997) 0.09 0.12 7.91

MTVV exp. (m/s²) (ISO 2631:1997) 0.08 0.12 7.14

Exposure duration: 05:00:00 Seat back contact time (%) : N/A





m/s1.75VDVexp ( ) 51.9 (z direction) Time to 17 m/s1.75 00:03:27



0.3 0.6 23.3 1.6

R Age (yrs)

20 30 40 50 60 65 0.8 1.2 1.5 1.8 2.2 2.5

79

Site/meas. no. Ip_veh8 Measurement date: 22/11/2006 Tape/ID no: 4/5

Vehicle: Harbour launch Seat: None, vibration measured on deck at operator's feet


1

10

1 100

(/

.

0.001

0.01

0.1

0.1 10 Frequency (Hz)

Acc

. PS

D m

/s²)²

Hz

x seat x seat base

1

10

1 10

/.

1

10

1 10

/s²)²

/.

0.001

0.01

0.1


Acc

. PS

D (m

s²)²/

Hz

0.001

0.01

0.1


Acc

. PS

D (m

Hz

z seat z seat base

y seat y seat base

80

81

Site/meas. no. Ip_veh8 Vehicle: Harbour launch


x seat

-5

0

5

0 0.5 1 1.5 2 2.5 30

10

20

y seat

-5

0

5

0 0.5 1 1.5 2 2.5 30

10

20

z seat

-5

0

5

0 0.5 1 1.5 2 2.5 30

10

20

Published by the Health and Safety Executive 02/08




The work reported here is the second part of a project looking at whole-body vibration exposure and other ergonomic risk factors for back pain from driving occupations. Phase 1 of the project is reported in RR612. The project is an exploratory study of back pain in drivers. The small sample size of the study means that it will not be possible to draw strong conclusions about relationships between exposure data and self-reported musculoskeletal disorders. However as future studies use the data collection toolkit developed during this project to add to the library of data, it will be possible to analyse the records for evidence of possible combined effects of whole-body vibration and ergonomic stressors as sources of back pain.

Phase 2 of the project, essentially a data gathering exercise, involved applying the toolkit to a number of vehicles. The part of Phase 2 concerned with port vehicles is reported here. Eight port vehicles were studied for this part of the project.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

RR613

www.hse.gov.uk

whole-body vibration and ergonomics of driving occupations › research › rrpdf › rr613.pdf ·...

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