More than half the motorists monitored by Norwich Union’s (NU) telematics devices are exceeding the government-recommended maximum journey time without taking a break, running the risk of fatigue-induced collisions, said the insurer.

Kay Martin, head of telematics, proposition and strategy for NU, said fatigue and nodding-off behind the wheel was one of the leading causes of collisions in the UK.

According to statistics compiled by the Department for Transport, 1,965 collisions and 69 fatalities were caused by driver fatigue in 2006.

Martin said the telematics programme – launched just over a year ago – had been invaluable in highlighting to fleet managers the mistakes and risks drivers were taking by measuring the length of travel, speed and time of day of each journey.

Telematics is connected to global positioning system technology and integrated with computers and mobile communications technology. The technology monitors a motorist’s driving behaviour and then transmits the information back to the insurance company.

Martin said: “Some companies have already received three reports from us, so it’s enough time for us to spot trends – one of the main areas of concern to us is driving duration.”

She added that it was too soon to determine whether telematics had been successful in reducing the number of collisions compared to last year but NU believed it was invaluable to road safety.

Royal & SunAlliance and Brit also offer telematics.

The parent companies of AXA and Groupama are understood to be trialling the system.