One leading construction chief executive said that the cost of installing hands-free sets in company fleets would run into thousands of pounds.
He said contractors intended to protect themselves from legal acton by issuing written guidance to employees warning them of the dangers.
However, leading construction lawyer Rudi Klein said contractors must go further than simply telling staff to avoid using conventional mobiles while driving. He said that a contractor must change the way their employees' contracts are worded to eliminate liability – which could also cost firms thousands of pounds.
To be safe the employee doesn’t have a mobile in the car or doesn’t use it for company business
Construction lawyer Rudi Klein
Klein, who is also a specialist in employment law, said that it was generally understood that an employer could be held responsible if an employee caused an accident while on the phone on business. He said this also applied to drivers of cranes and other vehicles on site.
He said: "The employer is always at risk in this situation. If the employer wants to be absolutely safe then the employee doesn't have a mobile phone in the car at all or doesn't use it for company business."
Klein added that employees' contracts would have to be amended in order to stipulate exactly what company journeys were used for. He said that journeys needed to be confined to getting from A to B, leaving mobile phone use "outside the scope of employment".