Drivers who use their car for work are more than twice as likely to fall asleep behind the wheel as the rest of the driving population.
A new survey by road safety group, Brake, found that one in 10 business drivers admit to having fallen asleep behind the wheel in the past year. That drops to one-in-25 for those who dont drive for work.
Brake points to a shortage of sleep among business drivers as one of the main reasons for the increased level of fatigue behind the wheel.
Half of business drivers surveyed admitted to driving after less than five hours sleep, compared with 35% of other drivers.
With the Corporate Manslaughter Act due to come into force in April, employers risk prosecution after a road accident involving an employee if they cant show that adequate steps were taken to keep their drivers safe.
Brake is urging business drivers and their managers to set realistic schedules, and to have an in-depth safe driving policy.
Head of campaigns for Brake, Cathy Keeler, said: 'Too many people are dying on our roads because people get behind the wheel when impaired through tiredness.
'Its crucial that companies introduce thorough procedures to ensure employees are not endangering themselves and others when driving for work.'