Soft-tops will fall outside the new law if drivers light up with the roof down after July 1.
Fleet management company Masterlease is calling on all businesses to self-regulate their employees by introducing a smoking moratorium, regardless of the car being driven.
The company believes the government should close the ‘topless’ loophole ahead of July. It also claims prohibiting smoking will save businesses money.
Gavin Jones, head of risk management at Masterlease, said: ‘The best policy is to ban it completely because it is the companies that will be vicariously liable to face fines if their staff are reported.
‘The application of the Department of Health’s regulations highlights a loophole that drivers could currently exploit.’