About 45 per cent of heavy vehicle drivers who caused accidents in the last five years were foreigners, said Parliamentary Secretary for Home Affairs Amrin Amin.

These included work permit and S-pass holders, he told Ms Joan Pereira (Tanjong Pagar GRC) in Parliament yesterday.

There were an average of 791 accidents with injuries involving heavy vehicles and 39 fatal ones each year during this period, he added.

Responding to Ms Pereira on measures to boost enforcement, he said the Traffic Police (TP) will deploy speed cameras that can compute average speeds in enforcement zones from next year.

These cameras will ensure motorists drive at safe speeds along the entire stretch, he said.

This year, TP will also conduct a tachograph trial on heavy vehicles to track and record their speeds in addition to other information.

"Companies that are involved in the trial will be able to track their drivers' tachograph records, and improve their drivers' driving behaviour," said Mr Amrin.

Such measures complement road safety education initiatives, such as a movement to encourage drivers to use their road sense launched two years ago.

On ensuring foreign drivers are trained to drive safely, Mr Amrin said that since last year, such drivers have to obtain their driving licence within six months of getting their work pass, instead of within a year previously. Drivers' licences must be renewed every five years. This subjects foreign vocational drivers to the same requirements as locals before they are allowed to drive heavy vehicles here, he noted.

Ms Pereira also asked whythere are still cases of heavy vehicles speeding, given that such vehicles have been equipped with speed- limiting devices.

Mr Amrin replied that although speed limiters were introduced in 1999, some heavy vehicles still exceed the speed limit. This could be due to faulty speed limiters or tampering, he said.

He warned against tampering with speed limiters, and said TP has stepped up enforcement to detect and deter such acts.

Those found driving with a faulty speed limiter or tampering with them can be jailed up to three months or fined up to $1,000.

The main causes of accidents involving heavy vehicles were failure to keep a proper lookout, failure to give way to traffic and failure to maintain proper control.