Most people who drive as part of their jobs get no extra training or safety advice, a motoring organisation claims.
Most drivers do not get training on basic vehicle checks, a survey found
A survey by the Institute of Advanced Motorists (IAM) suggests 75% of working drivers get no assessment of their skills or extra training.
It is estimated 1,000 people a year die on the roads "at work". Van drivers, pizza delivery riders and sales people are particularly vulnerable.
One in five of the 1,000 surveyed said they had driven while using a phone.
The institute is asking the government to fund extra safety courses.
The survey found 70% of respondents said their employers neither offered or required medical check-ups, with 64% saying they did not even require a basic eyesight test.
A total of 70% also said their employer did not offer training on basic vehicle safety checks.
Nearly half of employees in the survey admitted that pressures from their employer or work lead them to break the speed limit or lose their temper with other motorists.
The motoring body said it is estimated that a 1,000 people a year are killed while driving for work - nearly a third of all road deaths. Another 13,000 people a year are seriously injured.
IAM Chief Executive Christopher Bullock said the body was "shocked by the scale" of the findings in its survey.
"Too many employers think their responsibility for employees when they're at work ends at the front door or the factory gate," he said.
"Employers who fail to look after staff who are out on the road risk accidents that can result in employees being killed. Quite apart from being irresponsible, it is bad for their business."
The institute has backed a recent report by the government's motorists forum which called for a new work-related driving safety programme.
Ministers recently launched a programme of free advanced driving lessons for van drivers in an attempt to make them more considerate motorists.