Title: The Problem of Fatigue and Drowsy Driving in the U'S'
1The Problem of Fatigue and Drowsy Driving in the
U.S.
- John Caldwell, Ph.D.
- Air Force Research Laboratory
- Brooks City-Base, TX
- john.caldwell_at_brooks.af.mil
2Fatigue is a problem throughout America
- In the past century, Americans have reduced their
sleep time by 20 (from 9 hrs down to 7 hrs a
night). - Since 1969, we have added 158 hours a year to our
working and commuting time. - Over 25 million people now routinely engage in
shift work.
3Complaints about sleepiness are growing across
the U.S.
- Only a half of all adults are satisfied with the
amount of sleep they get (they are getting an
hour a day less than what is recommended). - More than one-fourth say that they are sleepy at
work 2 days per week or more. - Ten percent occasionally or frequently fall
asleep at work. - One out of five say they make errors at work due
to sleepiness. - Many admit that on-the-job sleepiness impairs
concentration, lowers productivity, and degrades
work quality.
4Much of this sleepiness is simply due to chronic
sleep restriction
VIGILANCE TASK PERFORMANCE
Balkin et al., 2000
5Sleepiness creates particular problems late at
night
- Since fatigue is a function of hours awake and
time of day, alertness suffers the most late at
night - Micro-lapses into sleep are rare during the
daytime (even between 1700 and 2200). - Unintentional sleep episodes steadily increase
between 2400 and 0800. - Increased lapses at night partially explain why
accident rates often are higher at night. - Night workers are more likely to make a variety
of performance errors than day workers due to
sleepiness.
6Alertness and performance are clearly influenced
by time of day
11000
10000
9000
Meter Reading Errors
8000
7000
6000
5000
4000
Midnight
6 a.m.
6 p.m.
Noon
Midnight
Time of Day
Mitler et al., 1988
7Fatigue has become a major problem on U.S.
highways
- Tour bus crashes in 98 and 99 focused attention
on hours of service regulations for drivers - Insufficient rest is thought to be responsible
for driver errors. - Fatigue made the top 10 list of transportation
safety issues because of trucker crashes - Thirty-one percent of all trucker fatalities are
fatigue related. - Driver drowsiness causes 100,000 accidents, 1,500
fatalities, and 71,000 injuries annually, and
costs the U.S. 12.5 billion a year!
8Driver sleepiness has reached alarming proportions
- A 1999 National Sleep Foundation survey of the
general public found - 62 reported driving drowsy in the past year
- 27 had actually dozed off at the wheel
- 23 knew someone who had experienced a
fall-asleep crash - Fatigue-related crashes are especially frequent
at times that coincide with low points in the
bodys circadian cycle
9Fatigue-related collisions increase at certain
times
2 AM
2 PM
Source M.M. Mitler, M.A. Carskadon, C.A.
Czeisler, et al.
10Unfortunately, crash statistics seriously
underestimate the problem
- Only half of crashes are reported (Miller, 1991)
- 6 states do not have fatigue codes (NSF, 1998)
- Most police are not trained to detect fatigue
- There is no objective measurement (e.g., blood
test) - Self-reporting tends to be inaccurate
- Drowsiness is often linked to other factors
(e.g., alcohol, drugs)
11One drivers experience with drowsy driving
12Increased litigation and civil penalties have
made falling asleep at the wheel no laughing
matter
Thag Anderson becomes the first fatality
as a result of falling asleep at the wheel.
13Families have been devastated by drowsy driving
14Commercial and Govt organizations are getting
the message they can be held liable for driver
fatigue
15Individual drivers are learning that falling
asleep is no excuse
16Characteristics of drowsy driving crashes
- Most happen between midnight 600am in the
midafternoon (circadian dip) - The driver is alone and more likely to be male
- A single vehicle drifts off the road and hits a
stationary object - Most are rear-end or head-on collisions
- There is no evidence of braking or evasive
maneuvers - Many involve serious injuries and/or fatalities
(Pack, 1995)
17Risky situations
- Think twice about getting behind the wheel if
- You are sleep-deprived or fatigued (whether from
shift work, sleep deprivation, or chronic sleep
restriction) - You know you are suffering from insomnia, poor
quality sleep, or a sleep debt - You plan to be driving long distances without
proper rest breaks - You will be driving through the night, the
mid-afternoon or when you would normally be
asleep -
(Knipling, 1994)
18Risky situations (cont.)
- Think twice about getting behind the wheel if
- You are taking sedating medications
- You have been working more than 60 hours a week
- You are working more than one job and your main
job involves shift work - You have been drinking even small amounts of
alcohol - You will be driving alone or on a long, rural,
dark or boring road
19Certain demographic groups are of particular
concern
- Young people
- Shift workers
- Commercial drivers
- People with undiagnosed or untreated sleep
disorders - Business travelers
- The elderly
20What are the warning signs of highway drowsiness?
- Difficulty focusing or keeping eyes open
- Trouble keeping your head up
- Yawning repeatedly
- Wandering, disconnected thoughts
- Feeling restless or irritable
- Trouble remembering the last few miles driven
- Drifting from your lane
- Tailgating or missing traffic signs of exists
21As individuals, what can we do to protect
ourselves?
- Before a trip, be sure to
- Get a good nights sleep
- Travel with a companion
- Schedule regular stops every 100 miles or every 2
hours - Avoid alcohol and sedating medications
- During a trip, if you do feel drowsy
- Stop driving and find a safe place to take a nap
or spend the night - Drink coffee or consume a caffeinated drink
- Get off the road if you hit shoulder rumble
strips
22As professionals, what can we do to help everyone
else?
- The first key is education!!
- The National Sleep Foundation has a number of
resources check out www.sleepfoundation.org - Educational materials can inform everyone of the
facts - Professionally-produced videotapes and
informative talks can bring the message home - Next, we should make sure and design highway rest
facilities that appeal to those most at risk!! - If they dont like their rest facility options,
theyll just keep going until their physiology
(or a bridge rail, telephone pole, or an oncoming
car) stops them!
23US Air Force Research Laboratory Aviation
Sustained Operations Team
State of the Art Fatigue Management for Americas
Air Force
For more information, contact Dr. Lynn Caldwell
at 210-536-3640 or lynn.caldwell_at_brooks.af.mil Dr.
John Caldwell at 210-536-8251 or
john.caldwell_at_brooks.af.mil