On Sept 15, our Public Warning System (PWS) sounded ("SCDF to sound sirens islandwide"; Sept 14).

Our PWS was originally a mechanical siren system inherited from the British, and then improved upon in the 1990s with the advances in technology.

Perhaps we should move along with modern technology to incorporate SMS blasts, in-app notifications and auto-call messaging for such important messages and warnings.

With the current system, the public is expected to tune in to important broadcasts on Singapore's FM radio stations.

Perhaps we could have members of the public dial a hotline and listen to the same message over the phone instead.

It would not be wise to replace the traditional bricks-and-mortar method, as that is the most reliable way to alert the public in wartime scenarios.

But we need to complement it with more effective practices as public behaviour and technology advance.

Dan Boon Jiahao