Last Saturday, the Singapore Civil Defence Force (SCDF) sounded a minute-long "important message" signal through the Public Warning System (PWS), an islandwide network of sirens.

According to the SCDF's website, the signal also sounds on smartphones that have the SGSecure mobile app downloaded and that are not on silent or vibration mode.

This signal stops once the message is acknowledged or after 20 seconds have passed. This is followed by a brief text on the PWS signal.

The website also says that upon hearing the "important message" signal, tune in immediately to any local radio station or television channel for a two-minute message on the PWS. I heard the announcement on the radio about the minute-long siren, but was not impressed with the exercise.

I recently experienced a 5.3-magnitude earthquake in Tokyo in the middle of the night. My cellphone suddenly emitted a series of long beeps and then I received a message saying an earthquake had just occurred and that I should seek safe shelter.

As a tourist in Japan, I did not have to download any app like SGSecure in order to receive this critical information. I was using a roaming SIM card for my entire stay in Japan.

The PWS is an outdated system. In the event of a real and possible disaster, no one would have the time or presenceof mind to tune in to the radio or television as suggested by the SCDF website.

It is time to upgrade the PWS so that everyone can receive a clear warning message in an emergency.

John Jee Wai Hin