Jeremy Hay, chief executive of safety consultancy Risk Answers, said he was told by many fleets that they were 'waiting for something to happen' before taking the plunge.
But Hay told delegates: 'It has already happened. Headlines tells us this. One company director is already in jail because of a company driver. You have a professional responsibility to do something about it.'
Hay said on many occasions drivers were tasked with taking a delivery to a certain destination through the night.
'It could be from somewhere in Scotland to somewhere in London and the driver has to be there by a set time. To get there on time he must travel at 95mph. Is that his fault? No. That's what he gets paid to do.'
Hay added that a recent survey conducted by his company showed that most company directors were unaware that they had the same liability for employees who used their own vehicles to drive on company business as they did for those allocated with a company car.
He added that 3% of drivers also had the wrong type of licence for at-work driving.
'There's so much to know,' Hay said. 'It's not a low priority. Companies pay about £4,000 per employee to train them how to use a new computer, but when they get a £25,000 car employers just give them the keys.'
Driver vetting should start the moment a prospective employee is being interviewed for a job.
He said: 'They should be asked if they have been involved in a serious accident on the road that has resulted in a fatality. How do you know you haven't got a psychopath behind the wheel?'