Canadian Trucking Association September 1996 1 - Canadian Trucking Association - Straight Talk on Fatigue and Alertness
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Canadian Trucking Association – Straight Talk on Fatigue and Alertness
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Canadian Trucking Association
September 1996
1Canadian Trucking Association – Straight Talk on Fatigue and Alertness
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Copyright @ 1996 Canadian Trucking Association
This document is protected under the copyright laws of Canada and is not to be copied by any
means whatever, in whole or in part, without the express written consent of the Canadian
Trucking Association.
ISBN 0-920969-70-4
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ACKNOWLEDGEMENTS
The Canadian Trucking Association would like to express its appreciation to transportation
consultant John Pearson for his efforts in researching a large amount of complex material and
distilling it into a text that captured the ideas we were trying to convey, and to Dr. Ron
Heslegrave for his expertise and patience in editing and finalising the material. We would also
like to thank he Project Alert working group of carriers and trucking association staff from
across the country for their valuable input, as well as the highly skilled professional drivers who
shared their knowledge and insights with us.
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TABLE OF CONTENTS
INTRODUCTION .......................................................................................................................... 5
The Consequences of Fatigue ..................................................................................................... 6
Circadian Rhythms and the Human Body Clock........................................................................ 7
Sleep and Sleep Hygiene .......................................................................................................... 10
FATIGUE IN TRUCK DRIVERS – A REVIEW OF THE RESEARCH ................................... 13
RISK FACTORS IN TRUCKING................................................................................................ 14
Driver Type............................................................................................................................... 14
Environment.............................................................................................................................. 15
Time of Day .............................................................................................................................. 16
Sleepiness.................................................................................................................................. 16
Evaluating the Risk of Fatigue.................................................................................................. 17
At Home.................................................................................................................................... 20
In the Cab.................................................................................................................................. 22
CONCLUSION............................................................................................................................. 25
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INTRODUCTION
Operator fatigue has long been recognised as a key safety issue in all transportation modes –
road, rail, air and marine. Fatigue in the trucking industry is now receiving increased attention
from researchers and regulators, due largely to the inability of traditional methods of regulation
to adequately address the safety impacts of fatigue in commercial drivers. This issue is further
fuelled by the generally held view in North America that 5 to 10 per cent of all heavy truck
accidents are fatigue-related and that operator fatigue accounts for 30 to 40 per cent of heavy
truck fatalities. Also, a disproportionately high share of night-time and single-vehicle accidents
can be attributed to fatigue.
To being to address the problem of driver fatigue, the Canadian Trucking Association’s board of
directors, in 1996, made it clear that the industry needs to act now on what is known about driver
fatigue and what can be done to implement countermeasures. While work continues by
government and the industry to review the current regulatory environment and search for
effective and practical improvements, CTA has taken the first step in a countermeasures program
by developing Straight Talk on Fatigue and Alertness as a plain language guide to the fatigue
issue.
This booklet is intended to provide drivers, safety personnel and trucking company managers
with :
· a basic overview of fatigue – its causes and effects
· some of the research findings to date, and
· tools and tips to help drivers maintain their alertness
Driver fatigue is a complex issue, and the purpose of this publication is to serve as an
introduction. Additional material, including audiotapes, pamphlets and books, will be made
available throughout the industry to supplement the information contained in this booklet.
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FATIGUE AND ALERTNESS : AN OVERVIEW
The Consequences of Fatigue
For the purposes of this guide, fatigue is a term used to describe a condition where drowsiness
results in a loss of alertness and impairs a driver's ability to perform tasks that require attention.
As with other forms of impairment, people often have difficulty recognising and accepting their
reduced capabilities due to fatigue and therefore may resist taking corrective action at the right
time. While people have little difficulty recognising physical tiredness, they have trouble
detecting the more subtle signs of mental fatigue and fail to appreciate the impact that these
subtle changes have on their performance. In addition, the ways in which fatigue affects
performance vary a great deal from one individual to another.
While fatigue affects everyone differently, some common consequences of fatigue include:
· reduced alertness - less capability to respond to the demands of the job
· reduced concentration - more difficulty with decision-making and reasoning
· impaired memory - shorter attention spans
· poorer task performance - reduced ability to respond with sufficient speed and accuracy
· irritability and depressed mood
· drowsiness
· increased likelihood of "microsleeps" -brief 4-5 second sleep periods that a person usually
does not know are happening
· lower resistance to the effects of alcohol and drugs
· higher risk of illness
While there are a number of techniques which may be helpful in recognising and managing the
symptoms and in providing temporary relief, the only real remedy for fatigue is sleep.
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Circadian Rhythms and the Human Body Clock
Our basic biological processes (e.g. body temperature, blood pressure and hormone release)
follow a cycle that recurs about every 24 to 25 hours. These daily patterns are referred to as
circadian rhythms, which are largely controlled by an internal body clock located in our brain
(See Figure 1 ). One important circadian rhythm is the sleep pattern where we sleep at night and
remain awake during the day. There are several triggers to help the biological clock maintain a
24-hour cycle. The most important of these triggers is the presence of daylight and darkness, but
the timing of such things as meals and social interaction also plays a role.
The human body responds to its internal clock in different ways from morning to night :
· the presence of bright light in the morning tells the brain it is time to become active
· mental and physical alertness rises and remains at a high level throughout the morning hours
· a modest decline in alertness will normally be experienced during the early afternoon
(sometimes called the "post-lunch dip")
· alertness rises again in late afternoon, often peaking for the day in the evening hours
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· the onset of darkness begins a process within the brain to prepare us for sleep a few hours
later
· during the hours between midnight and dawn, significant biological changes occur within the
body: temperature drops, the heart slows and blood pressure falls - even if we are awake
· with these changes, a major drop in alertness and increased drowsiness can be expected
between midnight and dawn, with the lowest level of alertness occurring between about 2:00
a.m. and 5:00 a.m.
While everyone has circadian rhythms, the length of the cycle, and the size and timing of the
peaks and troughs in the cycle vary from one person to another. There is also evidence that an
individual's cycle may vary slightly from one season to another, with the consequence that
periods of drowsiness may be more frequent during the winter months.
So What Does The Body Clock Have To Do With Fatigue and Alertness?
The circadian cycle is a fact of life and a potentially valuable indicator of when fatigue is likely
to occur. Regardless of what a person is doing, fatigue will occur during the low points in the
cycle, i.e. early afternoon and during the night (see Figure 2). If a person is already fatigued at
the start of the day, the circadian cycle will still remain, but that individual will be less alert
during the day and drowsier at night.
Shift workers are also affected by the same circadian cycle, even if they regularly start work
during the evening or night hours. While some people believe that their internal clocks readily
adapt to night work schedules, the reality is that this rarely happens. Therefore, people who begin
work at midnight are still likely to experience a decrease in their alertness and increased
drowsiness during the hours between midnight and dawn. Moreover, these night shift workers
will have more difficulty sleeping during the day, even though they may be extremely tired,
because their body clock expects them to be awake at this time.
There is growing evidence of a link between the dips in the circadian cycle and accidents in the
workplace and elsewhere. Figure 3 shows the relationship between fatigue-related traffic
accidents and time of day. In spite of much lower traffic volumes, the increase in the number of
accidents, which occur on the highway in the very early morning hours, coincides with the
trough in the circadian cycle and the increased effects of fatigue that can be expected to be
present during this time.
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Sleep and Sleep Hygiene
Simply stated, fatigue-induced impairment arises as a result of the body's need for rest and sleep.
Within the circadian cycle of about 24 hours, everyone needs a certain amount of sleep to fully
"recharge the batteries". The amount of sleep that is needed varies between individuals, but is
usually between 6 and 8 hours per day.
Obviously people can and do continue to function without getting the right amount of sleep
every day. However, the body keeps a running account of the amount of sleep that is missed, and
"a sleep debt" is built up if people continually get less sleep than they need (see Figure 4). As
this debt accumulates, people will suffer from steadily reduced alertness and increased
drowsiness, which can seriously impair performance. Sleep debt, like other kinds of debt, must
be repaid. The body naturally repays sleep debt in two ways: people sleep longer than usual, and
the type of sleep they get is much deeper. For most people, the first opportunity to repay this debt
comes on their days off.
Ideally, people's lifestyles would allow a waking-sleeping routine to be adopted which provides
the right amount of sleep needed each day, taken at the right time based on their circadian cycle.
Under these conditions, there would, in theory, be no sleep debt carried over from one day to the
next, and the body would be fully restored each day. However, in real life this rarely happens
because of the demands of the workday combined with social and domestic activities.
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For a variety of reasons, a large number of people are unable or unwilling to respect their daily
sleep needs, and have what is called poor "sleep hygiene". In other words, their sleep habits do
not allow them to have a healthy, restorative sleep.
People who suffer from sleep disorders are faced with much greater difficulty in meeting their
daily sleep needs. The quality of their sleep is often poor, with frequent interruptions and less
deep sleep. Consequently, while they may have been in bed for the 6 to 8 hour period
theoretically needed, the value of the sleep obtained may be equivalent to only a 3 or 4-hour
period of good sleep.
For people with a sleep debt problem, daily sleep needs can also be met by conscious use of
naps, or short-term sleeps to supplement a longer term "anchor sleep". While the mechanics of
sleep are complex and involve several stages of activity within the brain, there are some
guidelines emerging to obtain the greatest benefit from an adequate anchor sleep supplemented
by naps:
· An anchor sleep should ideally be taken at night ; however for night shift workers, this
anchor sleep should be taken whenever a period of at least 6 hours without disruptions is
available. How long you sleep depends largely on when you go to bed. A recent survey of
over 5,000 shiftworkers shows that the length of sleep taken during daylight hours decreases
as bedtime gets later (see Figure 5).
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· Naps should be taken when needed, generally at the low points in the circadian cycle, and
should not be so long as to reduce our ability to sleep during the anchor sleep period. It has
been shown that naps as short as 20 or 30 minutes can have a positive effect on alertness.
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FATIGUE IN TRUCK DRIVERS – A REVIEW OF THE RESEARCH
There has been a great deal of research carried out on fatigue in the transportation sector, with
particular emphasis on operators, due to the safety-sensitive nature of their jobs. In recent years,
several studies of fatigue in truck drivers have been carried out, perhaps most notably a joint
Canada-U.S. cooperative study of 80 drivers operating on regularly scheduled, revenue routes.
In general, the results of the studies on fatigue in truck drivers are consistent with the findings of
research in other transportation sectors. While several trucking-related studies are still in
progress, key findings that have emerged to date include the following :
· Truck drivers are sensitive to the influences of circadian cycles, showing greater signs of
fatigue in the period between midnight and dawn than at other times of the day (regardless of
the time the on-duty period began).
· The influence of the circadian cycle on fatigue appears to be greater than the time on duty or
the number of hours of driving.
· Night shift drivers show higher incidence of fatigue than day shift drivers.
· Driving schedules, which require a different start time from one day to the next, result in
higher levels of fatigue than regular schedules having the same start time each day. Driving
schedules with earlier start times each day are particularly difficult to deal with. For example,
a driver on a rotation of 12 or 13 hours on duty followed by 8 hours off duty for several
consecutive days may experience a sensation similar to jetlag, because the daily sleep-wake
cycle (20 or 21 hours) on this type of shift rotation is less than the human body's natural
circadian cycle (about 24 hours).
· Truck drivers, like people in other occupations, do not easily recognise and respond to the
subtle signs of fatigue onset. As a consequence, drivers may often continue to drive beyond
safe limits.
· The type of vehicle configuration appears to have little impact on the fatigue experienced by
drivers; i.e. double and triple trailer combinations are no more fatiguing than single trailers.
Perhaps the most compelling outcome of the research completed to date relates to basic
weaknesses in the regulations governing the hours of service for truck drivers. While it may
seem logical to place strict limits on the number of hours that a driver can work, this approach
does not consider important factors such as the impacts of the circadian cycle, the quantity and
quality of sleep obtained, and a driver's general fitness for duty.
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RISK FACTORS IN TRUCKING
While fatigue affects everyone, some types of people and occupations are more susceptible to the
impact of fatigue. Certain risk factors have become recognised as important contributing factors
to the onset of fatigue. The full range of human, environmental, time-of-day and sleep factors,
which have been identified as contributors to fatigue, are at play in the trucking industry. To
predict the likelihood of a driver becoming impaired by fatigue requires consideration of each of
these factors, individually and in combination.
Driver Type
People with Sleep Disorders
Any disorder or condition, which reduces either the quantity or quality of sleep obtained, will
contribute to a higher incidence of fatigue-related impairment. People who suffer from sleep
disorders, such as insomnia or sleep apnea, run a higher risk of being drowsy while on duty and
are more prone to impairment from fatigue. Those at the highest risk of developing sleep apnea
are males, people over fort y, overweight people and those with sedentary lifestyles. Any
combination of these factors increases the risk.
Younger People
There is evidence that people under age 25 are more prone to fatigue. This is generally attributed
to a combination of the need for more sleep than older people, coupled with lifestyle factors that
interfere with the amount of sleep obtained. In a recent study of fatigue-related traffic accidents it
was found that 55% of the drivers were under 25 years of age.
Older People
Drivers over 50 also appear to be more susceptible to the effects of fatigue. This may be part I y
due to the higher incidence of sleep disorders in older males, as well as the fact that older
workers (even those as young as 40) have more difficulty coping with the fatigue associated with
shift work.
Day & Night People
It is well recognised that some people feel more alert early in the day and have greater difficulty
functioning late at night. Such people are known as "larks" .The opposite type, or "owls", prefer
to stay up later at night and find working in the early morning to be a real challenge. While both
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types of people will have difficulty working through the night, "owls" should be more effective
on night shifts, and "larks" will perform better on early morning starts.
Environment
Monotonous Driving Conditions
Driving conditions with little change in the environment are more likely to increase fatigue.
These would include: driving through featureless countryside; travelling a freeway rather than a
two-lane road with oncoming traffic; low traffic volumes requiring less attention; and driving
during darkness when there are fewer outside distractions.
Long-Haul Driving
Relative to other types of work, long-distance driving poses a higher risk of fatigue. This could
be caused by the demands of maintaining mental alertness through long periods of performing a
monotonous or repetitive task.
Length of Trip
As with any task requiring continuous periods of concentration, some level of fatigue is likely to
occur on long trips as compared with short hauls. Therefore, it will be more difficult to remain
alert during long trips if they are taken without breaks or naps when necessary.
Temperature
Although the reasons are not clear, the onset of fatigue occurs more quickly in environments
where the temperature is either too warm or does not change. This applies not only to outside
temperature, but also to the environment inside the cab.
Unexpected Delays
In addition to the regular job demands faced by truck drivers, unexpected events such as
mechanical breakdowns, or delays at border crossings or inspection stations can prolong a trip
beyond the time that a driver would normally expect to be able to rest.
Unfamiliar Routes & Equipment
As with learning any new task, the requirement for a driver to learn new routes or to become
familiar with the characteristics of new equipment creates the need for increased attention and
concentration, often over a long time span. This additional demand on the driver can lead to
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greater fatigue from the increased workload.
Time of Day
As discussed earlier, the body's biological clock is a primary factor determining people's level of
fatigue. Between midnight and dawn, and to a lesser extent during the post-lunch dip in the early
afternoon, drivers will find it increasingly difficult to stay alert. On the other hand, when
working nights, people are in a constant struggle with their biological clock when they finish
work and try to sleep – their body rhythms are working to keep them awake through the day.
People who work irregular schedules also struggle against their circadian clock, which is trying
to keep them on the same sleep-wake cycle every day. The result is that both work and sleep will
be disrupted to some extent. This disruption is all the more serious when the combined sleep-
wake cycle is less than the body's natural 24 to 25 hour biological day.
Sleepiness
Sleep Quantity & Quality
As discussed earlier, the only real remedy for fatigue is sleep. People may be sleepy on the job
for a variety of reasons: sleep must be of both the right quantity and quality, but job and lifestyle
demands, particularly among truck drivers and other shift workers, often prevent good "sleep
hygiene".
People who wake up feeling unrefreshed are probably getting too little, poor quality or
fragmented (interrupted) sleep. The most effective sleep should be taken in a single "anchor
sleep" period, rather than being split into multiple segments. This should not be confused with
naps, which can have a beneficial effect when taken to supplement an anchor sleep. Each day of
restricted or poor quality sleep builds sleep debt, which will impact on driving ability, and must
be repaid by taking longer than usual and/or deeper sleep.
Drowsiness & Driving
Although drivers are most prone to fatigue during the overnight and early afternoon hours, job
performance at any time of the day can be impaired by reduced alertness following long hours of
waking since the last anchor sleep. For example, a driver who wakes in the early morning and
begins a shift in the afternoon - perhaps 8 or 10 hours later - is likely to feel drowsy in the
evening hours, when the body is beginning to prepare itself for the next expected sleep period.
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Drowsiness can also occur immediately after waking from brief sleep periods such as naps. In
these circumstances, a person will need a short time, perhaps only 10 or 15 minutes, to recover
from this "sleep inertia" and be alert. If sleep inertia lasts longer than this, it is probable that the
nap was not long enough for good recovery, and more sleep is needed.
In all cases where drowsiness occurs while driving, it is important to accept and act on any early
warning signs, such as those described in the section "Self Assessment".
Alcohol & Medications
Alcohol, controlled substances and some types of medications can have negative effects on
alertness or create drowsiness. Some medications, both prescription and over-the-counter, such
as cold remedies or other medicines containing alcohol, antihistamines or codeine, can reduce a
driver's ability to function properly. This can be especially serious if these medications are taken
at times when a person would already feel drowsy, such as during the night or early afternoon.
Also, some people will have one or two drinks shortly before bed to try to relax and fall asleep.
However, this may disrupt sleep patterns and prevent a person from getting the amount of deep
sleep needed to feel fully rested. Sleeping medications, while appropriate under some
circumstances, can leave people feeling groggy if the medication is still in their system when
they wake up. This might be expected if some types of sleeping pills are taken before a nap or
short sleep ; it is always a good idea to get a doctor's advice before taking sleeping medication.
Evaluating the Risk of Fatigue
Each of the factors identified above can contribute to the likelihood of a driver experiencing
fatigue while on the job. While these factors will affect different people to different degrees, the
risk of fatigue occurring during a trip could be expected to increase with the number of factors
present.
Table 1 summarises the factors which might contribute to the risk of encountering drowsiness
while driving. While researchers have not yet quantified this risk, the greater the number of
factors listed in Table 1 which apply to a particular trip, the higher the risk of fatigue on that trip.
For example:
· a day person (column 1)
· who is overweight (column 1)
· driving on a freeway (column 2)
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· between midnight and dawn (column 3)
· for the third night in a row (column 3)
· who has slept 3 hours less than normally needed (column 4)
would be considered to be at high risk of becoming drowsy some time during that trip, especially
when alertness is at its lowest point between 2:00 and 5:00 a.m. Under these circumstances, extra
precautions would be warranted to help the driver maintain the necessary level of alertness. An
effective counter-measure for this particular trip might be a nap before extreme fatigue sets in.
However, longer-term remedies may also be called for, such as weight loss, improving overall
sleep hygiene and (if operational constraints permit) a driver scheduling change.
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DEALING WITH THE RISK OF FATIGUE
Up to this point, the causes and effects of fatigue have been discussed, and some of the
underlying risk factors that can lead to fatigue on the job have been summarised. So what can be
done to reduce the chances that a driver will become drowsy while on the road, and what steps
should be taken if fatigue does occur?
As mentioned earlier, the only real remedy for fatigue is sleep, and sleep must be of the right
quantity and quality to restore the level of alertness needed to drive safely. However, at some
point during a long trip, the chances are that a driver will feel some level of drowsiness,
particularly if working overnight. The following tips and suggestions are offered to help drivers
get the kind of sleep needed for the demands of the job, to stay alert while driving, and to spot
and react to the signs of fatigue when they appear.
At Home
Fitness and Diet
Improved physical fitness helps to maintain alertness while on the job. Although long working
hours make it more difficult for drivers to maintain a fitness routine, as little as 30 minutes of
moderate physical activity per day can be really beneficial. This activity time can be
accumulated, so that three periods of ten minutes spread throughout the day can be as good as a
half-hour of continuous activity. Walking, working in the yard, playing with the children, or even
housework can help.
A well-balanced diet and regular meals will also be helpful in maintaining a proper sleep-wake
cycle. A routine of three meals a day, with no more than five hours between meals, is the most
beneficial. A nutritious meal should be eaten before the beginning of a shift, and for night shift
drivers, a snack or light meal when drowsiness is most likely to occur - between 2:00 and 5:00
a.m. - will help keep alertness levels up.
Sleep Hygiene
Placing a high priority on getting adequate, good quality sleep during off-duty periods is a key to
minimising the likelihood of fatigue on the job. For commercial drivers, this is often one of the
most difficult adjustments to make. Long duty periods and a relatively short time between shifts
can present a real challenge to balancing family pressures, social activity and domestic chores
with the need for the right kind and amount of sleep.
However, poor sleep habits dramatically increase the likelihood of becoming drowsy while
driving. Prolonged periods of inadequate or poor quality sleep will inevitably lead to the build-up
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of sleep debt, which can present a real danger to commercial drivers. A person who normally
needs, say, six hours of sleep daily and has only eight hours between driving shifts, needs to
make a conscious effort to limit all non-sleep activities to two hours. This will be difficult,
especially for drivers with families, but giving the highest possible priority to sleep between
shifts will pay safety dividends in the long run. Making sleep a priority at certain times of the
day often leads to making social and domestic activities a priority at other times. This type of
"lifestyle scheduling" can provide the greatest benefits from both waking activity and sleep.
Night Shift Work
Shift work in general, and particularly night shifts, pose real challenges to getting sufficient,
good quality sleep. While there are both pros and cons to going to bed in the morning as soon as
possible after a night shift ends, some of the advantages are :
· it is possible to avoid morning sunlight, which signals the body clock that it is time to be
awake (obviously, a darkened bedroom will be needed for this to work)
· a person is likely to sleep longer, as the sleep period will continue into the body's afternoon
drowsy time
· a person will be awake during the afternoon or evening when friends and family are likely to
have free time
Other measures which can be helpful for shiftworkers include :
· avoiding alcohol, smoking and heavy meals immediately before going to bed
· avoiding napping shortly before the next anchor sleep
· maintaining a regular bedtime as much as possible
Support from Family and Friends
Maintaining a balanced lifestyle that incorporates good sleep hygiene practices is difficult for
most shiftworkers, and particularly difficult for those who work at night. The importance for a
night shift driver to sleep during the day must be appreciated and respected by others - friends,
neighbours, family, and of course those people who ring the doorbell or call when a night driver
is trying to sleep. Open communication with family and friends about the safety impacts of
inadequate sleep, scheduling some afternoon or evening time for social activities, disconnecting
the phone during the day and even putting a "do not disturb" sign on the front door may all be
helpful.
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In the Cab
Much research has been focused on ways to recognise early warning signs of fatigue, or to
temporarily reduce the impact of fatigue when it does occur. It is important to recognise, based
on both the research and the experience of long-time truck drivers, that drowsiness can set in
quickly and may impair judgement to the point that the warning signs are ignored.
Anticipating when fatigue is likely to occur can be based, in part, on recognising recurring
patterns of drowsiness in trips and work schedules, and planning breaks, naps and rest stops in
advance. For example, experienced drivers have found that drowsiness can often occur only two
or three hours into a trip. Based on this expectation, pre-selecting a rest area and scheduling a
stop for a break or a nap during this period will be beneficial.
Self Assessment
Since people react differently when under the influence of fatigue, there are no simple guidelines
for drivers to assess their own fitness for duty. However, a promising area of research involves
training drivers to better monitor their own physical and mental states to recognise the signs of
fatigue, and to take appropriate steps (e.g. breaks, naps or sleeps). Often, drivers who
systematically monitor their own level of alertness will discover patterns, causes and warning
signals of their fatigue, and will find the best counter- measures for themselves.
Signs of fatigue onset which have come to be recognised by experienced truck drivers, and
which should be guarded against while on the road include:
· difficulty keeping the eyes in focus
· frequent yawning
· loss of concentration and wandering thoughts
· reduced awareness of surroundings - e.g. apparent sudden appearance of other vehicles
behind or in front of the truck
· memory lapses -no recollection of driving the last few miles
· failure to check rear view mirrors as frequently as normal
· unconscious variations in speed
· erratic shifting
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· driving too slow or too fast
· drifting out of the lane
· missing a turn-off
Napping
There is growing interest among researchers on the value of napping as a way of counteracting
fatigue and restoring alertness. Short naps (even for as little as 20 or 30 minutes) as supplements
to major sleep periods are proving to be very effective in offsetting drowsiness, particularly in
night shift workers. The use of strategic naps as a fatigue countermeasure is gaining increasing
acceptance as an important, responsible component of good sleep hygiene and as a tool for
improving productivity and safety.
To minimise the effects of sleep inertia -grogginess following a nap - it is advisable to wait for
10 to 15 minutes after waking up from a nap before returning to the road.
Breaks
Taking breaks during periods of reduced alertness, or at times of the day when the risk of
drowsiness is higher, can help break the monotony of a long trip and stimulate mental activity.
During a break, it is advisable to get out of the cab, have a meal or snack if needed, stretch, walk
around, or even get a little light exercise if possible. Breaks every two or three hours are a good
way of maintaining alertness, but are not a substitute for a nap or sleep if the driver is
experiencing signs of fatigue.
Caffeine
Caffeine -from coffee, colas or chocolate bars -can stimulate alertness, but this effect will last
only for short periods of time. Caffeine is not a cure for fatigue, and provides only temporary
reduction of some of the symptoms of drowsiness. Also, excessive caffeine consumption can
create digestive problems such as heartburn; more importantly, too much caffeine can disrupt
healthy sleep patterns by making it more difficult to nap or sleep when required.
Radio or CB
Distractions such as listening to interesting radio programs or talking on the CB or cellular phone
can help stimulate alertness, particularly when a driver is bored or when there are few outside
distractions (e.g. at night or when there is little traffic). While these activities do not prevent or
cure drowsiness, listening to a radio talk show or staying in touch with the "outside world" can
provide some mental stimulation. It is wise to avoid listening to music when vulnerable to
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fatigue ; experienced drivers have found that listening to music during drowsy periods can make
them feel even more tired.
Cab Environment
The environment in the truck cab can have a direct influence on the level of drowsiness
experienced by the driver. While a noisy environment and rough ride may be fatiguing, an
environment that is too warm or quiet can also promote drowsiness. Under these conditions, it is
a good idea to vary cab temperature and noise level from time to time by turning down the heat
and/or opening the windows.
24Canadian Trucking Association – Straight Talk on Fatigue and Alertness
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CONCLUSION
Finding solutions to the problem of commercial driver fatigue is not easy – if it were,
researchers, regulators and the trucking industry itself would not be paying as much attention to
the issue. However, much can be done to help increase driver alertness by taking some common-
sense first steps, such as learning a little about how the body clock affects a person’s
performance, getting the right quality and quantity of sleep, recognising the warning signs of
fatigue, and taking action when these signs appear.
But the trucking industry is complex and operation factors, such as tight delivery deadlines and
the need to schedule driving shifts around the availability of qualified drivers, can make it
difficult to put some of the remedies in place. Longer term, more permanent solutions will need
the cooperative efforts of all the groups involved with the industry : drivers, their families, their
employers, shippers, governments, the scientific experts, and other road users. Fatigue is a
problem that is manageable and by following the steps outlined in this booklet, we can begin to
do just that – manage fatigue in the trucking industry.
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