Driver fatigue is a killer
Throughout Europe, falling asleep when driving accounts for 20% of serious collisions under monotonous conditions like motorway driving. High impact speeds are more likely to result in fatalities. As UK roads increasingly congest, business drivers feel compelled to leave earlier and return later to arrive at their destinations. This leads to them driving in the time between midnight and 06:00 when as many as half of the fatalities and seriously injured collisions occur.
Sleep can be complex. Being tired doesn't mean you will sleep well, ask any insomniac.
Common factors that affect sleep
§ Stress can affect sleep
§ Self-imposed sleep deprivation is associated with younger drivers up to the age of 30, where they fight the warning signs believing they are good enough to make the journey.
§ Sleeping with the constant interruption of waking to fight for breath as sufferers of Sleep Apnoea do every night, will mean waking as tired as they were when going to bed. Sleep Apnoea is a growing concern as it is linked to obesity. Apparently a third of the population is estimated to be obese. How many of these are drivers who are not sleeping adequately?
§ Then there is the age group approaching 60 who are susceptible to mid-afternoon body clock dips.
There are interventions that can help in these situations, ranging from stress counselling, breathing equipment, weight loss, and effective risk management. However, the driver or employer has to recognise the need for intervention.
What are the signs for a sleepy driver?
Yawning can tell us we are sleepy, some believe it is a demand for more oxygen to make us feel fresher, whilst some research shows it is a way of cooling our brain. In practice, yawning can be contagious when in company and repetitive once you start. When driving it prompts us to open a window for fresh air, turn up the radio and have a good stretch in the seat. Relief is short lived and can progress to Micro Sleeping. This is the time to take a break.
Micro Sleeping is possible with your eyes open. A fixed glassy stare straight ahead with no recognition of what you see, and no memory of sections of your journey is a typical experience. Falling to sleep when driving begins with slow closing of the eyelids followed by slow opening, usually lasting 5-7 seconds, but this can extend as micro sleeps progress. Needless to say that in both cases the eyes are unseeing, the brain is in light sleep mode. The vehicle may drift before the driver regains awareness, and in panic corrects direction or brakes violently. Following this the driver may be alert for a while, but if the micro sleep experience is ignored and the driver continues the journey it will happen again and progressively extend for longer periods. It's important to realise that a micro sleep of only 8 seconds at a vehicle speed of 70 mph means that the vehicle travels approximately 800 feet, at 30 mph it's 360 feet; and no one in control. Plenty of time to hit neighbouring vehicles, oncoming traffic, or road side immovable objects, and let’s not forget pedestrians.
If you are driving in this perilous state, what can you do about it?
The Highway Code advises drivers to take a 15 minute rest break in every two hours of driving. Park in a quiet area. Take a high caffeine drink, and then immediately take a short 15 minute nap before the caffeine kicks in, usually 20 minutes. A brief walk on waking to feel fresher will enable the journey to continue in a safer state. This is a proven method of combatting sleepiness that I first heard at a road safety conference in Dublin Castle several years ago. The presenter was, Professor Jim Horne, an authority on sleep behaviours and at the time was running the Loughborough University Sleep Research Centre. He gave a fascinating insight to the effects of driving whilst sleepy and what you can do to mitigate it has been a valuable lesson.
It is easy to say to those suffering sleep deprivation for whatever reason to seek a solution, your life will improve, and your journeys be safer.
Alert drivers need to be aware that within their vicinity there may be one or more drivers in a sleepy state. Vehicles drifting, slow reactions to events and auto-pilot facial expressions are recognisable behaviours that serve to ensure that you drive appropriately and avoid becoming a victim of a driver in a micro sleep.
Employers can be aware of sleep disorders and driver fatigue by conducting routine driver risk assessments. The ArriveSafe assessment flags this issue and there may be others that do too.
David Hayman: –
In grateful recognition of, Professor Jim Horne Sleep Neuroscientist – BSc, MSc, Phd, DSc, FSB, FBPsS, CPsych, CBiol
For more detailed information: - http://jimhorne./co.uk