Fatigue Risk Management for Operational Settings

Fatigue Science700 Bishop St, Suite 2000Honolulu, HI 96813

Fatigue is a Serious Concern

Expert consensus is that fatigue is“the largest identifiable and preventable cause of accidents in transport operations…”

Cited in a 2003 report, one safety study indicates fatigue may contribute to 20-40% of commercial transport accidents.

Other reports suggest that 21% of aviation incidents, 16% of marine vessel casualties, and 31% of fatal truck accidents are fatigue related.

Fatigue Factors

Sleep Restriction

Circadian Factors FATIGUE

Operator fatigue is a function of the sleep quality/quantity and the body clock.

Continuous Hours Awake (no sleep debt)

Blood Alcohol Concentration(BAC)

18.5 0.05 (significantly impaired)

21 0.08 (illegal to drive in Canada)

The effects of fatigue may be compared to the effects of blood alcohol levels

Blood-Alcohol/Fatigue Comparison

2 - 3 Drinks in 1 HourIMPAIRED

4 - 5 DRINKS = BAC 0.08 or 21

Hours Continuously Awake

People Often Restrict Their Sleep = Sleep Debt

Johnson et a. (2004). Modulating the homeostatic process to predict performance during chronic sleep restriction. Aviation, Space and Environmental Medicine, 75(3 Suppl):A141-6.

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Baseline Experimental Recovery

Vigilance Task Performance

Day-after-day of sleep restriction often is a bigger problem than long periods of continuous wakefulness

Sleep Restriction, Effectiveness, & BAC

After five nights of partial sleep deprivation, three drinks will have the same effect on your body as six would when

you've slept enough. National Sleep Foundation , 4/17/2009

Self-judgments of Fatigue Aren't Accurate

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Actual Sleepiness/Fatigue Self-Rated Sleepiness/Fatigue

Objective measures show fatigue progressively degrades cognitive

performance

Self ratings of fatigue fail to recognize all but the initial fatigue

effects!

Van Dongen, Maislin, Mullington, and Dinges (2003)

BUT

The Objective Fatigue Science Approach

Scientific Research shows that it is not possible for people to accurately assess their own level of fatigue.

We can predict fatigue based on sleep quality and quantity by using our Sleep Bands and validated software.

Accident Risk can be predicted based on the levels of fatigue.

How Data Is Collected and Processed

Wear the SleepBand for 7 days• Lightweight• Waterproof• Unobtrusive

Data is processed and fatigue /accident risk is determined by the US Dept. of Transportation validated SAFTE model.

Accident Risk Level Management Reports

Once the data has been analyzed the employer receives a summary Fatigue Accident Risk Report

Reports show where in the organization the fatigue risk is and the levels of fatigue/accident risk

For example, the reports can tell which shifts, locations, job type, etc. are responsible for any increased Accident Risk.

SleepBand Group Summary Data

Calculate group statistics

Reducing Accident Risk

Once the causes of the Accident Risk have been identified mitigation strategies are designed to reduce the risk.

Once the strategies have been implemented (usually 30-60 days) we have the workers wear the Sleep Bands a second time to make sure the Accident Risk has been reduced.

Fatigue Mitigation

Design/conduct mitigation strategy

Workshops/Classes Printed Guides

Summary of the Process

1st Obtain the baseline for organizational fatigue accident risk

2nd Once the sources and causes of accident risk have been indentified a mitigation strategy is designed to reduce risk that includes: worker training, schedule analysis, education.

3rd Re-access the fatigue accident risk in 30 to 60 days to determine the effectiveness of the mitigation steps and set new priorities

The SleepBand Program

For Additional Information Contact:John.caldwell@fatiguescience.com

Fatigue Science700 Bishop St, Suite 2000

Honolulu, HI 96813