The claim comes from How's My Driving, which operates a scheme putting badges on the back of vehicles asking 'How's My Driving' and offering a number for other drivers to call, or an email address to write to if a car is being driven badly.
As well as the sticker reminding employees to drive carefully every time they approach their cars, the firm also provides bright yellow key rings that carry the reminder.
The scheme, with each vehicle carrying a unique code number, is most familiar on lorries and vans, but it has been expanded to cover car and motorcycle fleets. Fleet safety expert Andy Price, an approved How's My Driving consultant, said the initiative, offered at £9 per vehicle per year, had reduced vehicle accidents by 67% on some fleets. He added: 'It can also diffuse difficult situations on the road, because if there is an incident, other motorists can ring a number rather than try to take up the problem with the driver on the road.
'This is designed to provide information to the fleet decision-maker, but we will not supply badges if a company is planning to use the calls they get for disciplinary purposes. This initiative is focused on improving safety by pinpointing where training is most helpful.'
Currently there are 30,000 badges in circulation, with the firm receiving about 30,000 calls and emails a year.
To encourage fleet drivers to accept the scheme, new round badges in several colours have also been created as an alternative to the black and yellow panels most often used on commercial vehicles.