The appeal by Ms Liu I-Chun to lower warning beeps to a safe level (Lower noise level in buses; Jan 1) has perhaps been misconstrued by Mr Wong Choy Siong (Warning beeps on buses are a good feature; Jan 3).

It is technically possible to set a safe and audible beep volume level like that of Hong Kong or Japan for all users, including the hearing impaired.

Better still, to increase the human touch and service, as what Japan and Taiwan do, have a microphone for bus captains to announce that the door is closing.

This is not an additional onerous task as the bus captains are just verbalising their own routine visual safety checks.

Commuters respond much better to a human voice than robotic loud beeps which become white noise at risk of being tuned out.

Lim Teck Koon