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Copyright of Shell International B.V. SLEEP AND FATIGUE OFFSHORE NOGEPA Meeting 20 th June 2019 Vanessa Riethmeister, PhD Health, Safety and Environmental Analyst IMPLICATIONS FOR FATIGUE RISK MANAGEMENT

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Page 1: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

SLEEP AND FATIGUE OFFSHORE

NOGEPA Meeting 20th June 2019

Vanessa Riethmeister, PhD Health, Safety and Environmental Analyst

1

IMPLICATIONS FOR FATIGUE RISK MANAGEMENT

Page 2: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V.

DISCLOSURE OF SPEAKER’S INTERESTS

(Potential) Conflict of Interest See below

Potentially relevant company relationships in connection with event None

• Sponsorship or research funding

• Fee or other (financial) payment

• Shareholder

• Other relationship, i.e. …

• Nederlandse Aardolie Maatschappij B.V. / Royal Dutch Shell

• Nederlandse Aardolie Maatschappij B.V. / Royal Dutch Shell

• /

• /

Page 3: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

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AGENDA

BACKGROUND

STUDY METHODOLOGY

MAIN FINDINGS

IMPLICATIONS

CONCLUSIONS

Q&A

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FRM – Fatigue Risk Management

FRMP – Fatigue Risk Management Plan

FRMS – Fatigue Risk Management System

Page 4: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

FATIGUED

TIRED

DROWSY

SLEEPY

NOT ALERT

4

Page 5: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

WHY IS FATIGUE A PROBLEM OFFSHORE?

• The offshore environment is a high risk environment in which consequences can be severe

• Fatigue is one of the major health & safety risk factors offshore ( e.g. due to shift work & consecutive long work days)

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Deep Water Horizon Disaster, 2010 Piper Alpha Disaster, 1988

* U.S. Chemical Safety and Hazard Investigation Board. Investigation report volume 3 drilling rig explosion and fire at the Macondo well. 2016; Report No.: 2010-10-I-OS.

• Fatigue offshore is not well understood

(e.g. causes, courses & etiology)

Page 6: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

SNAPSHOT OF CURRENT FRM PRACTICES OFFSHORE

• Significant variations of FRMPs based on country legislations and operating companies

• Existing work rostering (partially) based on FRMS (e.g. FAID®)

• In general, more attention is paid to night- and swing-shift workers than day-shift workers

• FRM protocol for HSSE-critical positions

• Fatigue awareness training for workers and supervisors

• Inconsistent use of Journey Management Plans

• Voluntary fatigue/fit-for-duty checks (e.g. the prior sleep/wake calculator)

6

There is still a lot to be learned and improved!

Page 7: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

OFFSHORE SLEEP AND FATIGUE STUDY

7

To better understand sleep & fatigue parameters during offshore shift rotations, to improve existing FRMPs

Prevalences, time courses and predictors of sleep and fatigue parameters were investigated.

OBJECTIVE

1. Cross-sectional mixed methods baseline study

METHODS

• Interviews (N=19), Focus Groups (N=47) & Questionnaires (N=260)

• N= 5 platforms (Dutch Central North Sea)

* Work Eat and Sleep: Towards a Healthy Ageing at Work Program Offshore. BMC Public Health. 2016; 16:134.

Page 8: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

OFFSHORE SLEEP AND FATIGUE STUDY

8

To better understand sleep & fatigue parameters during offshore shift rotations, to improve existing FRMP

Prevalences, time courses and predictors of sleep and fatigue parameters were investigated.

OBJECTIVE

1. Cross-sectional mixed methods baseline study

2. Intensive longitudinal repeated measures study (28-days)

METHODS

• N= 60 offshore day-shift workers (contractors & permanent staff)

• N= 4 platforms (Dutch Central North Sea)

• Bi-daily objective & subjective sleep and fatigue measures (pre-/post-shift, i.e. morning/evening measures)

• Statistical analyses: (Generalized) linear mixed model analyses

1 week 1 week 2 weeks

Page 9: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

SUBJECTIVE & OBJECTIVE MEASURES

• Sleepiness/Sleep quality (Karolinska Sleepiness Scale (KSS), Range [1-9])

• Reaction Times/Alertness

• Sleep parameters/Activity during the day

• Circadian Rhythms (Melatonin & Cortisol)

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Offshore Days: 2, 7, 13

Continuous

Bi-Daily

Bi-Daily Offshore

No Circadian shift detected

No significant changes over time

* Investigating daily fatigue scores during two-week offshore day shifts. Appl Ergon. 2018;71:87-94.

Page 10: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

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Page 11: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

PREVALENCES

• Cross-sectional data: • 73% reported prolonged fatigue

• 41% experienced a ‘Dip’, which 60% experienced on day 10/11

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

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Page 12: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 12

PREVALENCES

• Cross-sectional data: • 73% reported prolonged fatigue

• 41% experienced a ‘Dip’, which 60% experienced on day 10/11

• 1 in 7 offshore workers reported severe sleepiness (KSS>6)

each offshore day

• The average daily prevalence of severe sleepiness was 10% in

pre-shift and 19% in post-shift measures

• In the second week, 25% of offshore workers reported severe

sleepiness

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

Traffic light graphs. Percentages of employees in low (KSS≤3), medium (KSS=4-6) and severe (KSS>6) sleepiness categories over the course of a fourteen-day offshore shift period. Green columns indicate low, orange medium and red high fatigue risk.

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Daily Post-shift

Page 13: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 13

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

2,0

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Fatigue (KSS scores)

OFFHORE PERIOD

• Post-shift fatigue scores are higher & increase at a faster rate compared to pre-shift fatigue scores

• Peak of fatigue on day 10 (37%)

ACCUMULATION OF FATIGUE

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Daily prevalences of KSS>6 Pre-shift Post-shift

Page 14: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 14

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

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Acute/Chronic sleep loss Daily sleep loss Cumulative sleep loss

ACCUMULATION OF SLEEP DEBT

OFFHORE PERIOD

• Shorter sleep durations offshore

• Average daily acute sleep loss of 92 min

• Average chronic sleep loss of >2.5 consolidated sleep periods

TIB – Time in Bed TST – Total Sleep Time

Page 15: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 15

2,0

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PREVALENCES, TIME COURSES & PREDICTORS RESULTS

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PRE-OFFHORE PERIOD Preparation period

• SE% scores decreased, sleep latency, and duration

increased

OFFSHORE PERIOD

• Sleep durations, perceived sleep quality and level of rest

after awakening decreased

• Sleep loss and post-shift sleepiness scores accumulated

over the 14-day offshore work periods

• Post-shift sleepiness accumulation was significantly related

to successive days on shift and chronic sleep loss

POST-OFFSHORE PERIOD Recovery period

• Evening sleepiness scores were high and declined rapidly

SUMMARY

Page 16: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 16

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

End-of-shift effect – high and increasing post-shift fatigue scores in a 14-day offshore work period

Third-quarter-phenomenon – peak in fatigue scores on day 10/11 of a 14-day offshore work period

Spill-over-effect – leave periods affecting work periods and vice versa For example:

• High & rapidly declining fatigue scores and longer sleep durations in post-offshore work periods • Sleep banking strategies in pre-offshore work periods

POTENTIAL FATIGUE RISK PRONE PERIODS

Page 17: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 17

PREDICTORS (for individual sleepiness) • Suggestive evidence for differential demographic (age, chronotype), lifestyle (smoking, baseline fatigue) and health (BMI, mental &

physical health) predictors for pre- and post-shift sleepiness scores

low baseline sleepiness scores, older age, earlier chronotypes, smoking and poor level of mental & physical health

low baseline sleepiness scores, younger age, good mental and poor physical health

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

Post-shift

Pre-shift

Page 18: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL 18

PREDICTORS (for individual sleepiness) • Suggestive evidence for differential demographic (age, chronotype), lifestyle (smoking, baseline fatigue) and health (BMI, mental &

physical health) predictors for pre- and post-shift sleepiness scores

low baseline sleepiness scores, older age, earlier chronotypes, smoking and poor level of mental & physical health

low baseline sleepiness scores, younger age, good mental and poor physical health

PREVALENCES, TIME COURSES & PREDICTORS RESULTS

Post-shift

Pre-shift

Page 19: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

STRENGTHS & LIMITATIONS

STRENGTHS • Mixed methods design & Intensive longitudinal repeated measures study design

• Subjective & objective sleep and fatigue measurements

• (Generalized) Linear mixed model analyses

• Large offshore sample: including contractors, from multiple platforms

LIMITATIONS • Limited sample size in absolute terms

• Offshore logistics

• Bi-daily instead of hourly measures

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Page 20: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

CONCLUSIONS

• Study findings add new and unique knowledge to the existing sleep and fatigue literature

• FRMPs should focus on the whole offshore cycle, including pre- and post-offshore work periods

• All offshore workers (including day-shift workers and workers in non-HSSE critical positions) should be covered in FRMPs

• Prolonging offshore shifts beyond two-weeks will likely result in elevated fatigue/sleepiness risk

• Study findings provide important input for the advancement and optimization of existing FRMP and FRMS

20

Z Z

Page 21: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

RECOMMENDATIONS FOR (OFFSHORE) FRMPs

• Consider accumulating fatigue risk with consecutive (offshore) shift days

• Be mindful of potential fatigue risk prone periods (also applies to JMP & Road Safety)

• Develop Test (cost-effectiveness) Implement fatigue prevention strategies, e.g.:

• Pre-/Post-offshore work period fatigue checks

• Pre-HSSE critical tasks fatigue checks

• Real-time fatigue monitoring

• Sleep Hygiene education

• Caffeine intake/Napping strategies/etc.

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Data Privacy

Fatigued…what now?

Stigma/ Prejudice !

Intrinsically safe appliances

Page 22: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

Take home message

• Take the risk of fatigue serious as fatigue affects us all!

• Spent sufficient time on fatigue/alertness management

• Evaluate your own work/work environment and try to identify the fatigue risks and potential mitigation strategies

• Create a culture of trust where people can speak up when they are not alert to prevent mistakes and harm.

April 2019 22

Page 23: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V.

[email protected]

Thank you for your attention

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Page 24: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International B.V. CONFIDENTIAL

APPENDIX

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Page 25: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

FUTURE RESEARCH

Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical

fatigue prediction models of FRMS to ultimately improve health and safety of offshore workers.

Specific future research examples

• Cost-benefit analyses of the accumulated fatigue risk in extended offshore periods vs the additional commuting

risk in shorter offshore periods

• Effectiveness of fatigue proofing/prevention strategies offshore, including feasibility studies, impact assessments,

cost-efficiency studies and offshore worker satisfaction surveys

• Intensive longitudinal prospective studies of the consequences of accumulated sleep loss and fatigue

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Page 26: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

PVT-B ANALYSES

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Figure. Outcomes of the pre- and post-shift objective fatigue metrics, obtained from the psychomotor vigilance task (PVT-B), over the course of the two-week offshore day-shift periods. Means, standard errors and linear prediction lines are plotted for (1) reaction times, (2) number of lapses, (3) number of errors, (4) and number of false starts.

Page 27: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

CIRCADIAN RHYTHM ANALYSES

Date Month 2016 27 Footer

19:40

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Figure. Outcomes of the circadian rhythm marker analyses. Graph (1) depicts mean salivary cortisol levels and standard errors during the three sampling days (offshore day 2, 7 and 13). Graph (2) depicts dim-light melatonin onset (DLMO) times and standard errors across the three sampling days (offshore days 2, 7 and 13).

Page 28: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

KSS ANALYSES

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3,0

3,5

4,0

4,5

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5,5

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Post

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Post

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Post

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Post

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Post

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Post

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Morning Sleepiness

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Evening Sleepiness

Page 29: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

AVERAGE KSS PREVALENCES

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45,1

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14-day average

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Severe 11 8,5 8,9 7,7 13 13 14 17 18 22 17 14 18 19

Medium 33 45 43 45 42 43 43 32 43 38 50 40 34 38

Low 56 46 48 47 46 44 42 51 40 41 33 46 48 42

0%

20%

40%

60%

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100%

Daily Average

Page 30: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS

Copyright of Shell International CONFIDENTIAL

PUBLICATIONS

• Riethmeister V, Brouwer S, van der Klink J, Bültmann U. Work, eat and sleep: Towards a healthy ageing at work program offshore. BMC Public

Health. 2016;16:134.

• Riethmeister V, Bültmann U, Gordijn M, Brouwer S, de Boer MR. Investigating daily fatigue scores during two-week offshore day shifts. Appl

Ergon. 2018;71:87-94.

• Riethmeister V, Bültmann U, de Boer MR, Gordijn M, Brouwer S. Examining courses of sleep quality and sleepiness in full 2 weeks on/2 weeks off

offshore day shift rotations. Chronobiol Int. 2018; 35(6):759-72.

• Riethmeister V, Matthews R, Dawson D, de Boer MR, Brouwer S, Bültmann U. Time-of-Day and Days-on-Shift Predict Increased Fatigue Over Two-

Week Offshore Day-Shifts. Applied Ergonomics, accepted for publication.

• Riethmeister, V.; Bültmann, U.; de Boer, M.; Brouwer, S. Predictors of sleepiness in two-week offshore day-shift workers. Submitted.

Date Month 2016 30 Footer

Page 31: Sleep and Fatigue Offshore...Future sleep and fatigue offshore studies should build on the presented findings to further advance bio-mathematical fatigue prediction models of FRMS