Stay Awake at The Wheel: Where Next? Jim Horne (Loughborough, UK)
FALLING ASLEEP AT THE WHEEL Background Information
UK: Prevalence of Sleep-Related Collisions (SRCs) Ø About 10% of all road crashes largely due to sleepiness Ø 20% for major, non-urban roads Ø 50% for early morning on dull roads Ø Worse outcome because of the higher impact speed - no braking Ø Probably kills more drivers and passengers than alcohol
Highway Hypnosis Doesn t exist another name for sleepiness Roads Only unmask sleepiness don t cause it Early Morning Driving Dangerous if this is one s usual sleep time, and on monotonous road
Drivers ARE aware of sleepiness when driving But Don t remember falling asleep or being sleepy why? The brain can not remember: Ø being asleep - unless sleep lasts beyond 1-2 min will not remember microsleep Ø sleepiness can you remember being sleepy last night & when it began? (also cant remember hunger & thirst) No excuse for drivers falling asleep at the wheel
When drivers experience any effort to stay awake, and utilise methods to stay awake (cold air to face, turn up radio etc) : Driving ability is markedly worse
Other Effects of Sleepiness Ø Visual illusions - fatal attractions Ø Increased euphoria/optimism about driving ability Ø More risk taking Ø Distorted perception of impaired driving Ø Alcohol twice as potent when sleepy
Drivers are aware of sleepiness : So - give them reminders!
What to do in a 30 min Break outcome from our published research FIND SAFE PARKING SPACE THEN: Ø 150 mg caffeine (not effective for 20 min) Ø Followed by nap of max 15 min Ø Freshen up - 5 min Ø This advice is now in the UK Highway Code given to all new drivers
Alcohol + Sleepiness Ø Alcohol is soporific Ø Alcohol is twice as potent for an already sleepy driver Ø Breath/Blood alcohol levels are a poor guide to impairment in sleepy drivers (even 50mg% - adopted by many EU countries)
VULNERABLE GROUPS to be targeted 1.Young drivers sleepiness is worse 2. Obese truck drivers 3. Shift-workers after first night of 12h shift
1. Young Adults especially early morning, and in men# Need more sleep more impaired by sleep loss Sleep loss produces euphoria Overestimate ability to stay awake Peer pressure to drive early am? Sleeping passengers portend a sleepy driver Even low blood alcohol worsens sleepiness #Young women take fewer risks
2. Fall-asleep Truck Crashes Ø Twice as likely (as car crash) to result in death Ø Driver asleep is commonest cause of truck crash & most likely cause of truck & load being destroyed ( 1.5 million) Ø Largest single cause of death during any type of work (including building sites) Ø Usual crash barriers will not stop 40 tonne truck travelling at c80 km/h (speed limiter) Ø Drivers vulnerable to obesity and sleep apnoea
2.Truck drivers: undiagnosed obstructive sleep apnoea (OSA) Ø High exposure to driving 100,000km/year Ø Drive at night during the trough Ø Many obese many have undiagnosed sleep apnoea Ø There is a need for screening: Ø rapid, effective treatment Ø undertaken in positive manner Ø beneficial to driver Ø job not compromised
NOTE Trucker with OSA can drive 4.5h without break (reduced to 4h at night) Often at night during circadian trough Just in time delivery schedules
EU directive (91/439/EEC) harmonising driving licence regulations Over 20 years old doesn t cover OSA No consistency in the way OSA considered across the 27 member countries - most ignore the problem EU trucks have no country boundaries
3. Shift/Nightworkers Ø Homeward drive Ø Early morning Ø After 12h night-shift Ø Especially after first night on this shift Ø On a dull road Ø Dangerous combination unfit to drive Ø Employers should have more responsibility?
SUMMARY 1.These crashes are particularly bad 2. Sleepiness also worsens risk-taking 3.Drivers are responsible for falling asleep 4. Small amounts of alcohol worsen sleepiness Vulnerable Groups (suggested actions): *Young men early morning (more warning) *Truckers with undiagnosed OSA (screening) *Night-workers after first night (employers)
THANKS & DRIVE SAFELY