Micro sleep is where a driver of a vehicle momentarily falls asleep and awakes almost immediately. It is very common; the driver continues with his previous activity without interruption and usually drives along without any incident. However, if an oncoming vehicle cuts into opposite lane, or if the driver is negotiating a curve, or if the vehicle in front suddenly slows or stops, the normal reflexes are absent to react fast enough and an accident is the result.
It is noteworthy that such fatigue induced accidents have some common features. Single vehicle accidents where the vehicle has veered off the road, head on collisions, accidents occurring between 2 to 4 pm and 1 to 5 am and if the driver has been driving continuously for more than 5 hours are some typical examples of accidents caused by fatigue.
Alert drivers on the other hand can take evasive and corrective action assisted by their reflexes in most situations thereby avoiding or minimizing the effect of an accident
Fatigue and drowsy driving is a world wide problem. The Australian Transport Safety Bureau Fatality Crash Database Study of 2002 showed that 16.6% fatal crashes were fatigue related and the Ontario Ministry of Transportation recorded that in 2004, 17,8% of all fatal crashes and 25.5% of crashes causing injury were fatigue related. This is an under estimate of the problem as the causes of fatal accidents cannot be established unless there are witnesses and drivers will not admit to this subjective sensation to the Police.
It is a notable fact that the majority of accidents occur when the driver is on a return journey and very seldom when he is on the first leg of a journey. Careful reading of the newspapers would reveal that major crashes occur when the driver is returning after taking a group on a pilgrimage, after dropping a passenger at the Airport, when returning from a wedding, or late night party. Holidaymakers seldom meet with accidents during their “on” journey but are known to when returning from a “tiring” holiday. The same goes for Long distance bus and articulated vehicle drivers of Lorries, Vans and Taxis.
Politicians too are known to have met with accidents when returning after campaign meetings late at night when the driver has fallen asleep. Thus it appears that the problem could be more common than estimates show it to be and that it could be a contributory factor in almost every accident making fatigue the number one killer on our roads.
The Sri Lankan Law with regard to driver fatigue is defined in the Motor traffic Act in Section169 which reads thus:
- No person shall drive, or cause or permit any person employed by him or subject to his orders to drive any motor tricycle. van, any motor coach or lorry:
(a) For any continuous period of more than four and a half hours; or
(b) so that the driver has not at least ten consecutive hours for rest in any period of twenty four hours calculated from the commencement of any period of driving
2. For the purpose of subsection (1), any two or more periods of times shall be deemed to be a continuous period, unless separated by an interval of not less than half an hour in which the driver is able to obtain rest and refreshment.
It would be interesting to determine how many of our long distance bus drivers, including drivers from the Sri Lanka Transport Board are aware of this law let alone complying with these laws.
There is no doubt that the majority of these fatigue induced accidents are caused by a lack of rest or sleep, unsatisfactory sleeping arrangements for the drivers or by a combination of partying, dancing, exertion, alcohol etc. in the case of owner driven vehicles.
There are many other factors that alone or in combination that contribute to this problem. We have mentioned inadequate sleep or rest caused by social circumstances. Stress at work or working late hours, and doing more than one job resulting in keeping up at night and domestic issues whether children or partner related are also known to contribute to this problem.
There are a variety of health issues that result in sleepiness and fatigue in the daytime. These are either due to a disease condition itself or caused as a side effect of the medication used. One of the commonest of this causing interrupted sleep is sleeping disorders often labeled as “sleep apnoea syndrome” Most of those affected are heavy snorers and they could seek medical help as it is often a correctable condition. They are often overweight (Body Mass Index over 28), have a thick neck, often have nose and throat problems and often take alcohol at night.
Another group is men above the age of fifty years who may suffer from diseases of the prostate gland; the earliest symptom is nocturnal frequency of micturition/ urination causing the person to get up several times at night to pass urine.
Some common medical problems that cause drowsiness include Diabetes, Hypothyroidism, Epilepsy (where the drugs used to control it too cause drowsiness) Asthma and Narcolepsy. Substance abuse, an increasing problem amongst the young leads to a combination of sleepiness and risk taking behaviour which could result in dangerous consequences both to the driver and to other innocent road users.
Regular medications that could cause drowsiness include Sedatives, Antiemetics (to prevent vomiting), Cough syrups, Antiepileptic medication and Psychiatric medication.
Awareness is an important factor in dealing with this problem, awareness both by the driver and by passengers traveling in the vehicle. The behaviour of the driver should alert the passengers. Taking more risks, frequent yawning, nodding, blinking and disinterest in carrying on a conversation are some early indications. More alarming signs include the driver becoming irritable, restless, shifting about on seat, insisting one is alright when asked whether there is a problem, driving in a zigzag manner, missing road signs and irrational speeding and breaking.
In spite of such apparently obvious symptoms and signs, drivers are known to deny, sometimes even argue and dare that they are not sleepy. There are many reasons for this. The most important appears to be a poor knowledge of the onset of micro sleep and its disastrous consequences. They underestimate the levels of fatigue and its consequences and overestimate their ability to perform and overcome the effects of fatigue coupled with a low perceived threat of the dire consequences of an accident. Younger drivers look upon this situation as a personal challenge and may even induce the driver to “show off” by indulging in risk taking maneuvers.
Employed drivers of vehicles, especially heavy vehicles on the other hand have to deal with the pressure to perform and the threat of penalization if time deadlines are not kept. There is competition to sustain ones job and competition for passengers in the case of commercial passenger vehicles. In the case of non commercial vehicle there may be perceived or apparent loss of face before passengers who may be relatives, friends or peers. The immature driver does not want to admit that he is sleepy trying to pretend that he could rise up to expectations, but often fails.
The responsibility lies with us to employ strategies to deal with this problem. Education is the key to create greater awareness. Driving schools must be coerced into including lessons on fatigue and drowsy driving in their curricula. The media, electronic and print too must educate so called seasoned drivers who often say that they “know it all” on recognition within oneself and on the realities of fatigue, drowsiness and sleepiness and accidents.
We must not forget the employer’s responsibilities either, however difficult it may be in a profit motivated culture. Screening during recruitment is the best way to ensure safety before it is too late. Assessing personality characteristics of potential drivers, information on school records, work adjustment, responsibilities and personal interests would help. Introducing humane work schedules, realistic targets and managerial support to combat fatigue are essential.
Whatever is said and done the ultimate responsibility is with the driver. We could talk about awareness, concern for passengers and other road users, risk free driving and more. We can talk about legislation, implementation, punishment and threats. If the driver does not want to accept that he is sleepy, if he insists on continuing driving to complete the journey, however compelling the reasons, we can at least educate him on what he could do to overcome fatigue and drowsiness.
The first step is to plan one’s schedule before driving. One must plan to get at least six hours sleep before embarking on a long journey. Cut short your party time, do not overindulge especially with alcohol and finish packing well ahead of time. Map out the places that you could have a rest break or nap, and carry plenty of water to drink.
One should avoid medicines and substances that could cause drowsiness. You should ask your doctor regarding side effects of the medicines he prescribes and specifically find out whether they cause drowsiness.
The following are some examples of the ploys used by drivers to overcome sleepiness and fatigue while driving. Most are effective, if at all, for a very short period and the drowsiness soon comes back while continuing to drive. These include: opening the window to let air play on your face, adjusting the air conditioner to a cooler temperature, or splashing water on the face. Stopping the vehicle and going for a short walk, doing stretching exercise of arms and legs have not been shown to be beneficial except in the short term. Listening to the radio, turning on the volume loudly, talking to oneself or to passengers or even singing have not been proven to take away sleepiness. More misconceptions include taking a snack or even smoking, but the effect is momentary.
Over ninety percent of drivers believe that coffee relieves drowsiness and makes one alert. Research has shown that this is not true. Coffee on the contrary has no impact on regular drinkers. It needs at least two strong cups to act and takes 15 to 20 minutes to be effective. The effects wear off after a short while and thereafter it ceases to be as effective when drunk again.
So, what can one do if one is one feels sleepy or drowsy while driving but one needs to go on with the journey?
The most effective strategy is to stop the vehicle in a safe area for a POWER NAP. A power nap is a short period of deep sleep lasting less than 15 minutes when a drowsy person leans back and relaxes with the intention of falling asleep. One can set an alarm with a mobile phone. One should sit in a quiet place comfortably, ask others not to disturb you, shut ones eyes and one soon dozes off. One should wait for a few minutes after getting up till one is wide awake. One usually wakes up refreshed, and good for another 3 to 4 hours of driving. However rest breaks thereafter every 3 hours or so will help. A power nap however is best taken before the commencement of a journey and not sometime during the journey.
If this is not possible there are some other second best alternatives. The Americans believe that chewing constantly throughout the journey keeps them awake. It must be noted that sleepiness returns the moment one stops chewing and that this is the secret in using this method. The safest and easily accessible substance is chewing gum but if that is not available even a wad of clean paper would do. Most long distance drivers in Sri Lanka chew betel but since this is a health hazard we do not advise the use of this on a regular basis.
Having a spare driver to take over is of course another option.
There are electronic devices that have been devised to wake up sleepy drivers. These have to be switched on when the driver feels tired. We have already discussed some reasons why drivers do not want to reveal such a state. The sensors when switched on are programmed to detect abnormal steering patterns and other control changes.
Other varieties of sensors can detect frequent eyelid closures. These devices are expensive, difficult to maintain, not cost effective and have been shown to fail when most needed!
Thoughtful highway design is another effective tool in the fight against fatigue and drowsy driving. Regular rest areas and parking bays with adequate space are essential to encourage drivers to use them.
Rumble strips wake up a sleepy driver when a driver veers off the path. Shoulder edge rumble strips have been shown to reduce accidents from vehicles running off the road by 15% and centreline rumble strips have reduced head on collisions by 25%.
The purpose of this article is obviously highlighting the importance of fatigue, drowsiness, sleepiness, tiredness and weariness as contributory factors in most major and minor accidents. There have been many similar articles in newspapers before this. Some of your readers may take the trouble to read the entire article, others may not and still others may not even give it a glance.
We hope that some of our decision makers would take note and take action on some of our suggestions.
Education and awareness are the key elements in dealing with this problem. In today’s world of driven by the glitz of entertainment it is hard to get a message across over the media unless on advertises during an important cricket match! But this costs a lot of money and the take home message may soon be forgotten.
However there are catchment areas where drivers have to call on regularly, sometimes annually at least, to renew their payments, health checks etc. These include the renewal of the annual road license at the office of the Commissioner of Motor vehicles, Insurance companies, Driving Instruction Schools, The National Transport Medical Institute, (where drivers of heavy vehicles have a compulsory health check every 3 years), Schools and Police after traffic offences.
There are also organizations which meet regularly to discuss this problem of traffic accidents viz. Ceylon Society for the Prevention of Accidents (CESPA), National Council for Prevention of Injuries (NCPI), Sri Lanka Medical Association (SLMA). These institutions can combine to develop easy to read flyers on subjects such as this one which could be distributed to all drivers calling at these points. The cost for printing etc could easily be absorbed by the licensing authority by increasing its fees by a mere Rs.100.00.
Billboards at entry, exit and midway points along all major roads and highways must be erected to alert the driver on drowsy driving with appropriate slogans. Stickers on the dashboard of vehicles involved in long hauls would remind the driver and alert him on the consequences of drowsy driving.
Professor A. H. Sheriffdeen,
Emeritus Professor of Surgery,
Chairman, Road Traffic Accident Prevention Committee,
Sri Lanka Medical Association
This article is a summary of the seminar on “Fatigue and Drowsy Driving”. Contributing authors include: Prof. Shyam Fernando, Faculty of Medicine, Colombo, Dr. Asela Anthony, Registrar, National Hospital of Sri Lanka, Dr. Ravi Nanayakkara, Lecturer, AJMO, Faculty of Medicine, University of Sri Jayawardenepura, Ms. Santushi Amarasuriya, Lecturer in Psychological Medicine, Faculty of Medicine, Colombo. Eng. Anvar Bin Azhar, Consultant Safety Engineer |
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