DEVICES PART OF TRIAL SCHEME

I refer to John Barclay's letter headlined 'Bad drivers ignored' (South China Morning Post, January 6), concerning countdown devices at traffic lights.

The countdown devices for pedestrians currently installed at 10 sites are part of a trial scheme.

Under this trial we will evaluate the effectiveness of the device and pedestrians' response to it.

Overseas findings on similar countdown devices for motorists are inconclusive.

Some studies indicate that these devices may increase the risk of accidents at road junctions as motorists may react differently in the last few seconds of the green signal of traffic lights.

Motorists who decide to speed through the junction will subject the pedestrians there to greater danger, while motorists suddenly braking their vehicles will cause the vehicles behind to collide with them.

Moreover, as part of our traffic control system, we have advanced traffic adaptive control technology.

With this technology the duration of the green signal of traffic lights will automatically adjust and may vary from one cycle to another depending on the traffic conditions in the vicinity.

The countdown devices that are available on the market, however, operate on a fixed, pre-set basis which is unable to accommodate such variations.

The two systems, if used together, will cause confusion to motorists.

The administration will closely monitor developments on this front to further assess the effectiveness of such devices and their possible introduction in Hong Kong.

C. C. LI

for Commissioner for Transport