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FATIGUE MANAGEMENT
We call 'loss of alertness, drowsy driving and falling asleep at the wheel' - fatigue. So when you are fatigued any of these things can happen to you. Driver or operator fatigue has long been known to be a major safety problem in all forms of transportation: road, air and sea. Traditionally, restricting hours of work has been the main method of controlling fatigue in transportation. For example the eastern states of Australia have limits on hours of work and use logbooks to enforce them. Logbooks are very unpopular and many people try and get around them. Western Australia will not introduce logbooks to control fatigue. Instead Western Australia will use the Occupational Safety and Health Act 1984 to get employers and employees to operate a safer road transport industry.
BACKGROUND TO FATIGUE IS EXPLAINED
The WA Department of Transport, the industry and unions have collaborated to produce a Code of Practice for Commercial Drivers which sets standards for safe operations in road transport. It is summarised in this lecture. This training resource explains the background to the problems of fatigue we face daily. It aims to provide some help and advice for drivers and their families to manage their fatigue better. Managing fatigue doesn't stop when you leave the truck; it is a 24-hour operation that involves the whole family. So we'll look at the following issues in turn:
- what causes fatigue;
- what are the consequences of fatigue;
- what are the basic principles of fatigue management in the Code of Practice; and
- what steps can drivers take to better manage their fatigue.
MAIN CAUSES OF FATIGUE
Studies in WA and overseas have found several main causes of fatigue. These are:
- Body Clock Factors
- working when you would normally be asleep; and
sleeping when you would normally be awake.
- Sleep Factors
- getting less than normal sleep; and
- getting poor sleep.
- Work Factors
- working very long hours; and
- insufficient time to recover from work.
- Medical Factors
We look at each of these factors in turn.
BODY CLOCK FACTORS
Our body functions run on a repeated 24-26 hour cycle. For example, we normally sleep at a regular time during the night if work permits. Our body temperature, hormone release, toilet functions all run on a 24-hour cycle. The main function of interest to truck drivers is the 24-hour cycle of brain alertness and sleepiness. Everyone who works the day shift will be most alert during the day and most sleepy during the night. All the work they have to do is most easily, efficiently and safely performed during the day. If that person has to work nights, they will make more mistakes, be inefficient and find it hard to stay alert.
The basic reason all our bodily functions run on a 24-26 hour cycle is that we have a body clock that regulates these things. The body clock is partly controlled by light and dark during the day and partly by what you do. For a normal 9-5 day worker some of the things that happen to you as a result of the body clock are:
bright light in the morning tells the body clock to make you more alert;
during the morning the body clock keeps you alert;
after lunch (siesta time) the body clock will turn your alertness down for a couple of hours;
the body clock will make you most alert in the late afternoon and early evening;
darkness in the evening tells the body clock to turn your alertness down again so you can get ready to sleep; and
after midnight the body clock will turn your alertness right down so that you are pretty switched off between 2 am and 6 am. At this time all body functions are at their lowest level.
Because the body clock is partly controlled by what you do as well as by daylight you can change your body clock a bit. For example, if you normally go to bed at 8 p.m. and get up at 3 am, your body functions will be at their lowest before you normally get up. You have adjusted your body clock a bit earlier than most people. If you are a regular night shift worker your body clock will partly change so that you get some sleep during the day and work reasonably well at night. But no one can change their body clock to become a totally night person - the presence of day light stops the clock from being changed that much.
Working when you would normally be asleep and sleeping when you would normally be awake
What do these facts about the body clock mean for drivers and shift workers? Remember we said that the body clock controls your alertness and sleepiness. This means drivers are at their best, most alert and safe when working during the morning and the late afternoon and early evening. They are at their worst between midnight and 6 am when the body clock turns alertness right down. The road crash numbers show this to be true. Although there are fewer drivers on the road between midnight and 6 am, those drivers are much more likely to have a crash. One study suggests that driving at 3 am you are 40 times more likely to fall asleep at the wheel than if you where driving at 10 am.
Because the body clock turns down alertness after lunch (the siesta period), there is also a small increase in road crash rates at this time too. Not surprisingly the crashes at night and during the siesta period are more likely to be single vehicle crashes.
People who have to work nights may have to make up their need for sleep during the day. They are not likely to get enough sleep, if any, during the night. People find it more difficult to get sleep during the day, although they can usually get a nap during the siesta period after lunch. The facts are that night workers who have to sleep during the day get less and poorer sleep than those who sleep at night. Result? Night drivers will get around 2 hours less sleep than day drivers; it will be poorer sleep and they will feel more tired.
SLEEP FACTORS
Sleep is a part of life. Sleep is what really cures fatigue and sufficient sleep prevents fatigue. Most people report sleeping around seven and a half hours a day. Some sleep less than this during the night and make up for it in naps. So we should regard seven and a half hours of sleep as the normal need. If people have much less sleep than this they will suffer fatigue. They will feel tired and fatigued during the day; but these feelings will be much worse during the night due to the normal operation of the body clock turning alertness down.
People such as drivers who work very long hours are not going to have time for seven and a half hours of sleep. People need to wash, do domestic things and eat and talk to other people. These things will get done at the expense of sleep if there is little time.
Getting less than normal sleep and getting poor sleep
A study of truck drivers in WA shows that on any one day around 50% of drivers on the road worked more than 14 hours, and around 30% worked more than 16 hours. This leaves only 8 hours for everything else they had to do. Twelve percent got less than 4 hours of sleep on the road and 30% got less than 6 hours of sleep. Those WA drivers who got less than 6 hours of sleep reported 4 times as many dangerous things happened to them, when driving. So, getting enough sleep is essential to safety. And 6 continuous hours of sleep is the minimum drivers should aim for. Transport schedules should take this into account. There must be adequate time for 6 hours of sleep and some time for the driver's other essential activities built into the schedule.
Drivers who are working nights and getting little or no sleep at night are going to have to make up for it during the day. Because the body clock turns alertness up during the day, those drivers will get less and poorer sleep during the day. So, drivers should try and get as much sleep as possible at night, and take another nap during the afternoon siesta period if necessary. They should try and avoid schedules that make them work long hours at night, give little time for night sleep and compel them to sleep in the day. They will suffer less fatigue if you avoid these schedules.
People such as drivers who get less than seven and a half hours of sleep each night will build up a 'sleep debt' each day they miss some sleep. Like the interest on a bank loan the sleep debt will build up until it is repaid by one or more nights of longer hours of sleep. Each day a driver goes with less than seven and a half hours of sleep the more fatigued and more unsafe on the road he / she will be. So, every opportunity should be taken on days off for a good long night of sleep and preparation for long trips should include making sure the sleep debt from the previous trip has been repaid.
Taking naps at every opportunity is a good way of getting enough sleep - napping is good practice. But don't think naps are a substitute for 6 hours of continuous sleep at night. Naps are used to supplement a good sleep at night and help prevent sleep debt, but they are not as beneficial as a good sleep at night.
WORK FACTORS
Long hours of work make you fatigued in several ways. Long hours of work stop you resting and sleeping. Long hours of work may make you work during the night when the body clock turns alertness down. Long hours of monotonous work may make you bored and drowsy. Long hours driving a truck may make you feel more fatigued than sitting watching the footy.
Working very long hours and insufficient time to recover from work
The study of WA truck drivers showed many were working such long hours they could not get six let alone seven and a half hours of sleep, plus do all the other things they had to fit in their day. Trip schedules should be designed with the aim of giving drivers the chance to get at least 6 hours of continuous sleep preferably at night. They should also allow drivers sufficient time for all their other essential activities such as eating and washing.
If this is not happening and you are missing sleep each night you will build up that sleep debt. It is vital that you have adequate days off so that you can discharge your debt. If you are working long hours and missing sleep you will need to use two days off a fortnight to recover from the debt by getting good long sleeps.
MEDICAL FACTORS
There are a number of medical conditions that occur in around 10% of drivers that make them feel fatigued, such as being very drowsy during the day. If you don't work at night and you have the opportunity for enough sleep during the night and you still feel fatigued and drowsy during the day, you should consult a sleep doctor. Your own doctor should be able to refer you. If you feel this is a problem for you it is not sufficient to take sleeping tablets; they won't cure the problem.
Some illnesses such as diabetes, if not controlled, can make you feel fatigued too. This is an illness when your blood sugar level is out of control. Diabetes can occur in anyone and in varying degrees. It is easy to control.
Being over weight or obese is not usually regarded as an illness. However, being over weight does cause other problems that are illnesses. It causes high blood pressure and diabetes. It may also cause you to have medical sleep problems too. A diet high in fat that causes obesity may also cause you to feel drowsy at certain times of the day after meals.
It makes sense for all drivers to have regular health checks so these illnesses and medical problems are found before they make drivers unsafe or unable to do their job.
Medical sleep problems
Medical sleep problems can be treated and should not just involve taking sleeping pills. One medical sleep problem is called 'sleep disordered breathing or apnoea' and this is made worse by being over weight. Although most people over 50 years snore at night sometimes, for a few this is a serious problem. They have sleep apnoea. In these people the wind pipe collapses during their sleep resulting in too little air getting to their lungs. This wakes them up (and their partners). This can happen many times a night and it results in poor and little sleep. So they feel very drowsy during the day, especially during the siesta period. This makes them unsafe on the road.
Other problems are just plain falling asleep during the day with no obvious sleep problem at night (narcolepsy). This can be treated with 'stay awake' drugs. Some people also suffer from restlessness at night that keeps them awake. They find their legs keep moving. This too can be treated.
CONSEQUENCES OF FATIGUE
We called fatigue 'loss of alertness, drowsy driving and falling sleep at the wheel'. It is certainly all of these things and more.
Loss of Alertness - means you cannot respond quickly and safely to the task. You may miss spotting dangers. You may be slow at controlling the vehicle, so it runs off the road occasionally or you have a near miss. You are less vigilant and slow to make decisions.
Drowsy Driving - drowsiness means feeling sleepy, but not actually being asleep. The fact is that if you feel drowsy you may actually drift in and out of sleep briefly without knowing it. Drivers have been studied when drowsy and found to be asleep for many seconds at a time, and then wake up, without being aware of it. This accounts for some "run off the road" crashes. It is quite common.
Falling Asleep at the Wheel - this is obvious and happens in a number of crashes. These are typically very severe single vehicle, crashes where there has been no attempt by the driver to control the vehicle. The driver was clearly completely unaware of events before the crash. It is not often drivers will report that they were asleep but the evidence tells.
Poor Memory - Being pretty fatigued also affects people's memory. For example, they may suddenly become aware they have travelled 200 kms without knowing it. This is not a problem in itself, but forgetting to make a delivery or forgetting where things are is a big problem in a hectic schedule.
Bad Mood - Being very fatigued also makes people irritable. This may be unpleasant for them but it is even more unpleasant for those around them. Regular fatigue makes drivers' domestic life very difficult and they may find that their partners do not put up with them for long.
FATIGUE IS A SIGNIFICANT FACTOR IN TRUCK CRASHES
Fortunately crashes are rare events so any one person does not have a good idea of how many there are or what causes them. Main Roads WA have records of all crashes in WA. They have analysed crashes involving trucks to find out how many of these crashes are likely to be caused by fatigue. In WA over 3 recent years there were 102 truck crashes involving death. Fifteen of them were likely to be due to fatigue. Over the same three years in WA there were 488 truck crashes involving serious injury; 55 of these crashes were likely to have been caused by fatigue. There were very many more truck crashes that were not so serious; many of them involved fatigue too.
So in WA, fatigue is involved in about 15% of fatal truck crashes; and involved in about 11% of serious injury crashes. Many truck crashes kill and injure car drivers too. The number of truck crashes involving fatigue is higher in rural areas than in the metropolitan area. As many as 35% of rural truck crashes are believed to be caused by fatigue.
BASIC PRINCIPLES OF FATIGUE MANAGEMENT
A number of basic principles apply when developing a fatigue management system. The following are detailed in the code of practice and should be considered as the basis for most systems.
- Give a driver at least 24 hours notice to prepare for a working time period of 14 hours or more.
- A schedule should permit a solo driver to have the opportunity for at least 6 hours of continuous sleep in any 24 hour period and preferably between 10 p.m. and 8 am.
- Where night work exceeds two consecutive periods of work between 10 p.m. and 8 am compensation of more than one day off in 7 should be built into the work cycle.
- Minimise irregular or unfamiliar work rosters.
- Operate flexible schedules to allow for Short Break Time or discretionary sleep.
- Minimise very early departures to give drivers the maximum opportunity to sleep in preparation for the trip.
- When drivers return from leave, minimise night-time schedules and rosters to give drivers time to adapt to working long hours especially at night.
- Require a driver to present and remain in a fit state for duty including not being impaired by alcohol or drug use.
- Develop a written policy on fitness for duty in consultation with employees and unions.
- Provide an appropriate truck sleeper berth if drivers will need to sleep in the vehicle.
- Require regular assessment of a driver's health by a suitably qualified medical practitioner.
- Ensure that the medical assessment includes consideration of sleep disorders and other fatigue related conditions.
- Identify health problems that affect the ability to work safely, eg. diabetes.
- Provide appropriate employee assistance programs if necessary and practicable.
- Provide drivers with information and assistance to promote management of their health.
- Provide a working environment that meets appropriate Australian Standards for seating and sleeping accommodation.
- When drivers work a continuous rotating shift system with a shift roster of 5 days or more there should be 24 hours of Non Working Time between shift changes.
- Ensure drivers are counselled regarding off shift activities, ie. to avoid excessive drinking, fatty foods and moonlighting. Exercise is a good idea.
GUIDELINES FOR DRIVERS
From the research into driver fatigue we can make suggestions on how to help drivers manage their own fatigue and improve their quality of life. Drivers should be aware of the basic principles for managing fatigue laid out in the Code of Practice for Commercial Drivers. Nevertheless the following information may help you on the job.
LISTEN TO THE TICK OF YOUR BODY CLOCK
No matter whether you have adequate sleep or not, there are high points of alertness and low points of alertness (when you feel drowsy, or want to sleep). Lack of sleep just makes these feelings worse. You will feel most sleepy between 1 and 5 am, and between 1 and 4 p.m.. Obviously Mediterranean countries have adapted to these feelings by having a siesta. The trucker often is not so lucky. Your schedule may be so demanding, or because you have fallen behind schedule, you cannot get a good night's sleep and feel like a nap in the afternoon too. If this happens, listen to your body clock and schedule breaks for rest or naps during these periods. It is vital that if you do feel drowsy during these periods you get off the road. The likelihood of falling asleep when the body clock is set to its 'sleep' function is very much higher than at other times in the day.
DON'T MESS AROUND WITH YOUR BODY CLOCK
Try to stick to a regular sleep and waking routine on EVERY day of the week, so that sleep, meals and activity are always at the same time. That includes time off. This will improve alertness when awake and sleep quality. If your job makes you work different shifts then try and ensure you have at least 24 hours off to get a decent long sleep between shift change-overs.
GET RID OF YOUR SLEEP DEBT AS SOON AS POSSIBLE
Sleep debt is the accumulation of fatigue from several days of work with inadequate sleep. Sleep debt can be calculated by adding together the hours of sleep lost each day compared to your normal sleep. Losing 2 hours of sleep each day for 4 days will make you nearly as fatigued as losing one whole night of sleep. Plan your time off to ensure you have committed time for enough hours of sleep to cancel the debt. Avoid being tempted to go to parties and other social functions if they will eat into the time you should be using to discharge the debt. Work with your family and friends by communicating your needs for sleep to them.
PLAN YOUR TRIP TO INCLUDE TIME FOR SLEEP, FOOD AND REST
Most trip schedules will hinge on pick up and delivery times and dates. It's up to you to plan the details of your trip. In Western Australia we do not have the restrictions of driving hours and logbooks so you have more freedom to meet your needs for sleep. The WA code of practice provides standards and guidance on safe practices for work and sleep. Plan your trip with the locations of your favourite rest areas in mind. Allow extra time for naps should you find you need them. It is not good practice to delay your departure to as late as possible, so you have to drive flat out to reach your destination. This will not permit a discretionary sleep should you need it, because you feel tired, or feel fatigued because of sickness.
LEARN TO RECOGNIZE, ACKNOWLEDGE AND ACT ON YOUR SIGNS OF SLEEPINESS
A beginning driver has little experience of the signs of impending sleep. Indeed most drivers are poor judges of their own fatigue. Don't go to the extent of waiting till sleep happens in order to find out! When you are yawning, your eyelids are drooping, you are unaware of where you have been, and you find that the vehicle is wandering or losing speed. That's past the time to pull over. You can find out how sleepy you are by noting how long it takes to fall asleep. If sleep occurs within 5 minutes, then it was very likely to have been the time to pull over. If it takes you over 20 minutes to fall asleep, maybe you did not need to do so just yet. A nap taken before serious fatigue sets in is more beneficial than one taken when you are thoroughly exhausted and have exposed yourself to the risk of a fatigue crash.
WORK OUT HOW MUCH SLEEP YOU REALLY NEED
If you really have difficulty in knowing whether you are sleepy compared to other people, and pose a risk when driving, try answering these questions:
- Do you fall asleep after lunch?
- Do you fall asleep in a car at a traffic light?
- Do you fall asleep when sitting and reading?
- Do you fall asleep watching TV?
- Do you fall asleep sitting without activity, in a public place?
- Do you fall asleep when you are a passenger in a car?
- Do you fall asleep when lying down in the afternoon?
- Do you fall asleep when sitting and talking?
If you answered 'yes' to any question, you may not be having enough sleep. Falling asleep doing any of these things is unusual in someone who is getting enough sleep. You can work out the amount of sleep you really need by taking a week of regular sleep of 6 hours each night. Try doing this when you have the time on your holidays. See how you feel with 6 hours sleep. Then, take a few days of 6 and a half hours of sleep. How do you feel now? Better? Increase your sleep by another half hour for a few days. When you no long get any more benefit from increasing your sleep period, you have established how much sleep you really need. When you return from holidays to work keep a sleep diary to see how much less sleep you have obtained. Calculate whether you are cancelling your sleep debt during your time off. If not, your are becoming a hazard on the road and need to do something about it. You may be in the wrong job, or you need to cut back on work.
MANAGE YOUR FATIGUE AT HOME TOO
Good fatigue management doesn't finish when you get out of the truck. Time off should be used to recover from sleep debt. This means setting up conditions at home so that you can get as much sleep as you need. Talk to family and friends about this and adopt some of the suggestions for improving the conditions for sleep. There are 10 important factors to getting good sleep: minimise noise, light, heat, food, worries, irregularity, disturbance, domestic responsibilities, alcohol, other drugs and coffee.
DEVELOP YOUR TECHNIQUES FOR STAYING ALERT IN THE CAB
Even if we have adequate sleep, the monotony of a truck trip can impair our vigilance for hazards. If the truck is hot and the noise and route is monotonous every one will loose attention. But the driver who has insufficient sleep will be lulled into sleep. Most drivers develop mental games to help keep them alert during monotony. You can develop some yourself, ranging through the use of your CB radio to calculating distances.
TAKE ADVANTAGE OF EVERY OPPORTUNITY TO NAP
Taking a nap is not a sign of inability to cope with fatigue; it is best fatigue management practice. When any opportunity to nap and rest occurs, take it. If there is a delay in loading or unloading the vehicle, use it for a nap. Nowadays some airlines require cockpit crews to take it in turns to nap on long flights.
EAT AT REGULAR TIMES AND AVOID HIGH CALORIE AND FAT FOODS
You don't have to be over weight to be a trucker. Eating high calorie, and fatty foods especially, can make you sleepy even if you have had enough sleep; they could be fatal if you have had inadequate sleep and are driving at night. The typical Australian diet is too high in fat, sugar and salt and too low in carbohydrates and dietary fibre. This is not good for people who want to minimise their risks of health problems. Few people set out to eat a lot of fat, sugar and salt but they come with many of our favourite foods such as burgers, chips, fried foods and fatty sweets like ice cream. So we should cut down on these foods at home and on the road. What we should be eating instead?
Breads & Cereals - 4-5 servings daily selected from rice or pasta and bread.
Vegetables and Fruit - at least 4-5 servings daily of fresh, frozen or canned fruits and vegetables.
Meat and Meat Substitutes - 1-2 servings daily of lean beef, lamb, veal, chicken or pork.
Milk or Dairy Products - 3-4 servings daily of milk, cheese or yogurt.
Fats (Butter and Margarine) - maximum of 1 tablespoon of butter or table margarine daily.
It is bad practice to eat a heavy meal before going to bed. Going to bed on a full stomach can keep you awake. Do not eat a heavy meal between 2 am and 6 am when your body clock has told your digestive systems to slow down.
USE EXERCISE TO IMPROVE YOUR FATIGUE MANAGEMENT
Obesity will contribute to sleep problems, which cause excessive fatigue during the day. Exercise helps you keep fit and keeps your weight down and improves blood flow where you need it. Although trucking involves long periods of inactivity, take advantage of stops to get some exercise.
IF YOU FEEL LIKE USING MILD STIMULANTS, USE THEM ONLY WHEN YOU NEED THEM, AND BEWARE OF STRONG STIMULANTS
If you feel like using stimulants perhaps this is an indication that you are getting too fatigued, need more rest and sleep and that your schedules and rosters are too demanding. Caffeine in coffee and cola is an excellent mild, stimulant, but you will rapidly get used to it if you use it all the time. Avoid using it at home. Keep it for the trip. If you are using strong stimulants there is something wrong with your fatigue management strategy or your trip schedule. If you use stimulants, remember to use them only when you really need them, and when sleep cannot be obtained. They are not the cure for fatigue. Do not use them at a time when their effect will interfere with your next sleep. Remember amphetamines and other stimulants only delay sleep, and when they wear off you will be doubly tired.
CHECK OUT YOUR HEALTH REGULARLY
The older, and even not so old, person can have medical problems. You need to know if you have mild diabetes or any other medical conditions that could impair your driving and everyone's safety. You need to know whether you have medical sleep disorder. If you feel chronically tired despite a normal length of sleep, or if your sleep is very disrupted, you should seek medical advice. Something can be done about them to improve your health and thus your economic welfare.
COMMUNICATE WITH YOUR SUPERVISOR
The WA Department of Transport has worked with the transport industry to develop a code of practice for safe work practices in the industry. The code sets standards for duty of care under the Occupational Safety and Health Act 1984 for working and sleeping hours and many other matters. Your supervisor knows these standards. If your schedule and roster does not conform to these standards your supervisor should be notified. If this fails to improve the situation, a WorkSafe Western Australia inspector should be notified. The penalties for companies and drivers who fail to meet the code of practice are severe.
To make sure that you have fully understood all the training information, complete the Self Assessment Questions available on the Worksafe Website (www.safetyline.wa.gov.au). For any that you get wrong, look back at the appropriate section of the lecture and re-answer the question.
http://www.safetyline.wa.gov.au/pagebin/mechhazd0035.htm
August 2001
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