Driver fatigue

FISA Safety Bulletin

Tired drivers have slower reaction times and suffer from reduced attention, awareness, and ability to control their vehicles. Research suggests driving tired can be as dangerous as drink-driving.

Police statistics show that fatigue contributes to about 4% of fatal road crashes and 2% of all collisions in Britain. However, it is likely that the true figures are far higher because fatigue is hard to spot and, unlike alcohol and drugs, police can’t test for tiredness. Worldwide, it is estimated that between 10% and 20% of all road crashes are fatigue related.

Most sleep-related crashes happen on motorways and dual-carriageways, probably because of the monotonous road environment and lack of driver stimulation.

Fatigue is a major cause of road crashes in the UK

• 10–20% of all crashes are estimated to be caused by driver fatigue.
• drivers are 20 times more likely to fall asleep at the wheel at 6am than at 10pm.
• 1 in 8 drivers admit falling asleep at the wheel.

Crashes typically involve vehicles running off the road or into the back of another vehicle. They tend to happen at high speeds, because drivers do not brake before crashing, so the risk of death or serious injury is high.

Factors that contribute to driver fatigue

Many factors can contribute to driver tiredness and increase the risk of being involved in a fatigue related crash. These include:

• Lack of sleep or disturbed sleep: This could be due to disruptions in life such as a new baby, busy schedules or stress, or could be due to sleep disorders such as narcolepsy, insomnia or sleep apnoea.
• Time of day: The most common times for drivers with normal sleep patterns to fall asleep at the wheel are early morning (2am-6am) and early afternoon (2pm-4pm). These times are when the body clock reaches a natural dip, causing drowsiness and reduced concentration.
• Stress: Tiredness and difficulty concentrating are typical symptoms of stress.
• Irregular sleep patterns: This can be a problem caused by irregular work shifts and switching from day to night shifts without having sufficient time off in between for your body clock to adjust. Research has found shift workers are particularly high risk for sleep-related crashes.
• Driving for long periods: Research has found driving deteriorates after two hours of continuous driving, as you become less able to concentrate, and slower to react to hazards. The longer you drive, the more rest you need to recover driving performance. Breaks are therefore recommended every two hours.
• Vehicle engineering: Modern vehicles are usually quiet and comfortable for the driver, meaning a more relaxed drive. This can lull drivers, particularly in vehicles fitted with comfort-enhancing features such as cruise control.
• Medication: Some prescription and over-the-counter drugs can cause drowsiness. Medications may carry warnings that are not clear they impair driving, for example small print that only advises not to operate heavy machinery.

Signs of fatigue

Fatigue does not occur without warning, and most people recognise the symptoms but many still underestimate the dangers of continuing to drive while tired.

Warning signs include:

• increased difficulty concentrating
• yawning
• heavy eyelids
• eyes starting to ‘roll’.

How to manage the risks associated with driver fatigue:

• Tell your boss and/or doctor about health problems that affect your sleep.
• Get a good night's sleep before driving - aim for 7-8 hours.
• Make sure you take enough breaks while driving – at least every two hours.

Sleep disorders

Anyone who suffers from a sleep disorder that prevents them from getting sufficient sleep is likely to be excessively tired during their waking hours, and so to be at higher risk of falling asleep when driving. Those most at risk of suffering from a sleep disorder, such as sleep apnoea, include professional drivers. It has been estimated that such drivers are between 6 and 15 times more likely to have a road traffic accident than those without the condition.

This type of medical condition is often undiagnosed, and some drivers may be unwilling to seek help because they fear losing their driving licence. However, there are established treatments for sleep apnoea which allow drivers to retain their licence, and therefore, their livelihood. Anyone suspecting that they have a sleep disorder is strongly advised to contact their GP.

Driving hours

The main EU rules on driving hours are that you must not drive more than:

• 9 hours in a day - this can be extended to 10 hours twice a week.
• 56 hours in a week.
• 90 hours in any 2 consecutive weeks.

You must record all driving you do under EU rules on a tachograph.

Breaks and rest

The main points of EU rules on breaks and rest are that you must take:

• at least 11 hours rest every day - you can reduce this to 9 hours rest 3 times between any 2 weekly rest periods.
• an unbroken rest period of 45 hours every week - you can reduce this to 24 hours every other week.
• a break or breaks totalling at least 45 minutes after no more than 4 hours 30 minutes driving.
• your weekly rest after 6 consecutive 24-hour periods of working, starting from the end of the last weekly rest period taken.

Forest machines

Tractors that are exempt from EU rules are likely to be subject to GB domestic drivers’ hours rules unless you drive for less than 4 hours in a day or drive only off-road. Under these rules, drivers are limited to 10 hours maximum on-road daily driving. Off-road driving does not count towards this total if it is for agriculture or forestry. A record sheet, but not a tachograph, is required to be kept.