Fatigue Awareness for Transit

Operations

Transportation Disadvantaged Conference Amber B. Reep

Center for Urban Transportation Research, University of South Florida

Funded by the Florida Department of Transportation’s Florida Transit Training & Technical Assistance Program (RTAP)

www.floridartap.org

Course Overview

• What is Fatigue• Factors that Affect Fatigue• Signs and Symptoms• Types of Fatigue• Driving Affects on Sleep Deprivation• Incidents Related to Sleep Disruption• Strategies to Maintain Alertness

How many hours of sleep did you get last night?

A. 8 or more hours

B. 7 hours

C. 6 hours

D. Less then 5 hours

Why Should We Care about Fatigue?

• 33% of all drivers have fallen asleep at the wheel of something during their lifetime

• 56% of shift workers have fallen asleep on the job

• 55% of adults stated they experienced daytime drowsiness

The Human Toll• 100,000 fatigue related

collisions per year• 1,544 fatigue related

deaths per year

• Imagine:– A Boeing 727 crash

every six weeks

– Titanic sinking once a year

– The World Trade Centers being destroyed every two years

What is Fatigue?

• Fatigue is a complex state characterized by a lack of alertness and reduced mental and physical performance, often accompanied by drowsiness

• Misconception: Fatigue is not just falling asleep

Fatigue Signs and Symptoms

• Forgetfulness• Poor

communication• Impaired decision-

making skills• Lack of alertness• Nodding off• Slow reaction time• Microsleep

• Withdrawn

• Depressed

• Moody

• Quick to anger

• No sense of humor

• Lack of interest

• Always tired

Factors That Affect Fatigue

• Sleep loss and/or disturbed sleep

• Disrupted biological clock

• Excessive physical activity

• Excessive mental or cognitive work

• Monotony or familiarity

• Quality & quantity of sleep

Factors That Affect Fatigue (cont’d)

• Continuous hours of being awake

• Illness• Time of day/circadian

effects• Sleep disorders• Environmental

conditions (hot or cold)• Nutrition

Factors That Affect Fatigue(cont’d)

• Physical fitness• Drugs• Health• Age

Physical Fatigue

• A decrease in physical performance

• A feeling of muscle discomfort

• Lack of energy

Mental Fatigue

• Tired and drowsy due to loss of sleep• Loss of concentration and/or alertness• Diminished levels of creativity and logic

Accumulating a Sleep Debt

• Sleep loss is cumulative and builds a debt

• Most people get 1 to 1.5 hours less sleep per night than they need

• People whose sleep was restricted to 4 to 5 hours per night for one week needed two full nights sleep to recover vigilance, performance, and normal mood

• How do you get out of sleep debt? SLEEP

Circadian Rhythms

• Circadian rhythms are important in determining the sleeping and feeding patterns of all animals. Patterns of: core body temperature, brain wave activity, hormone production, cell regeneration and other biological activities linked to this daily cycle. – melatonin secretion by the pineal gland and– core body temperature.

Overview of biological circadian clock in humans.This diagram depicts the circadian patterns typical of someone who rises early in morning, eats lunch around noon, and sleeps at night (10 p.m.). Although circadian rhythms tend to be synchronized with cycles of light and dark, other factors - such as ambient temperature, meal times, napping schedule and duration, stress and exercise - can influence the timing as well.

What causes circadian disruptions?

• Shift work• Irregular schedules• Emergencies• Illness• Children• Storms• Telephone• Restless Spouse

Biological and Social Effects on Shift Workers

• 60 to 80% affected by chronic sleep problems

• 4 to 5 times more likely to have stomach disorders

• 80% affected by chronic fatigue

Biological and Social Effects on Shift Workers (cont’d)

• 5 to 15 times more likely to suffer from mood swings and depression

• Divorce and spousal abuse rates higher• Drug and alcohol abuse rates higher

Driving Drowsy Affects Performance Like Driving Drunk

• 19 hours without sleep is similar to a BAC of .05%

• 24 hours without sleep is similar to BAC of .10%

0

0.02

0.04

0.06

0.08

0.1

0 hours 19 hours 24 hours

Pe

rce

nt

(%)

Who’s At Risk?

• People with lack of sleep• Driving patterns

– Midnight till 0600 am– Mid-afternoon– Many miles– Many hours– Monotony

Incidents Related to Sleep Disruption

• Chernobyl 1:23 am• Bhopal 12:40 am• Three Mile Island 4:00 am• Exxon Valdez 12:04 am• Most single vehicle 3-5 am

truck accidents

Incidents Related to Sleep Disruption (cont’d)

• Most mistakes by omission 3-5 am– Surgeon– Nurses– Postal Works– Telephone Operators– Railroad Employees

Who Pays the Costs?

• Insurance Companies• Families• Friends• The Company

Counter Measures• Create an optimal sleep environment

– Pillow and Mattress– Bedroom Location– Cool room– Family Ground rules– NO LIGHT– Quite– White noise– Routine

• Strategic naps• Proper nutrition and exercise• Prepare for schedule changes• Readjust your body clock

Supervising Employees

• Do you really notice the operators?• Do you talk to them?• Could you send a fatigued operator home?

Strategies to Maintain Alertness

• Drive defensively• Eat something light on your layover• Physical discomfort

– Heat– Cold– Uncomfortable seat

• Physical fitness• Rumble strips

Be Proactive

• Maintain/encourage healthy life style• Compensate and be aware of shift changes• Understand your bodies sleep needs• Maintain your sleep environment

– Minimize light, disruptive sounds, etc.

Questions?

The Transportation Safety Institute (TSI) developed a course that offers more information and training

about Fatigue Awareness