A new study by US researchers has suggested that blue LEDs (Light-emitting diodes) in truck cabs and truck stops can help to increase the alertness of drowsy drivers by resetting their body clocks, thus helping to reduce accidents.
According to a report in New Scientist, scientists at Rensselaer Polytechnic Institute, New York, did the study.
The scientists are testing blue LEDs that shine light at particular wavelengths which convince the brain that it is morning, therefore, resetting the body's natural clock.
That could help reduce the number of accidents that occur when people drive through the night.
Nearly 30% of all fatal accidents involving large trucks in the US happen during the hours of darkness, according to a recent report by the Federal Motor Carrier Safety Administration, while fatigue causes half of all truck accidents in the early hours on UK motorways.
"The concept of using light to boost alertness is well established in other areas," said Mariana Figueiro, co-author of a new white paper published by the Rensselaer Polytechnic Institute 's lighting research centre.
"Translating that understanding into a practical application is the next challenge," she added.
The researchers envision drivers taking 30-minute "light showers" in truck stops fitted with similar lights to recharge themselves. Otherwise, the lights could be fitted into truck cabs as well.
Figueiro is currently investigating how the blue light affects daytime alertness of sleep-deprived and non-sleep-deprived subjects.
"These findings will also be applicable to transportation applications, since the accident rates during the afternoon hours are still higher than in the morning hours," said Figueiro.
Results so far show a clear effect on the brain activity of test subjects of both kinds.
"After 45 minutes there is a clear effect," said Figueiro. "You start to see a beautiful increase in brain activity in the 300 milliseconds response, which is a measure of alertness," she added.
Figueiro now plans experiments on a driving simulator using different light spectra, of 450 and 470nm, and intensities of 2.5, 5 and 7.5 lux, to see which combination works best without obscuring the driver's view of the road.