Government officials will NEVER ask you to transfer money or disclose bank log-in details over a phone call. Call the 24/7 ScamShield Helpline at 1799 if you are unsure if something is a scam. For details, visit the ScamShield website.
To help businesses reduce regulatory compliance costs, SCDF will implement three-year Fire Certificate (FC) validity periods for renewal applications from 1 Apr 2026 onwards. Please refer to the SCDF Fire Certificate webpage for more information.
SCDF will be conducting essential system maintenance from 12 Feb to 16 Feb to improve our service delivery capabilities. For details, visit here.
As part of Exercise SG Ready, some pages on the SCDF website will be temporarily unavailable on 1 Feb 2026, from 3pm to 4pm, to simulate digital connectivity disruption.

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About Civil Defence Shelter Public Warning System Types of Shelter Regulating Civil Defence Shelter Acts and Requirements Waiver Application on Civil Defence Shelter Requirements

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Public Warning System

A network of sirens that the SCDF has placed at strategic points throughout the island, to warn the public of imminent threats that could endanger lives and property.

The Public Warning System (PWS) Various Signals & Meanings

The Public Warning System will be used to warn of attacks from the air, land or sea, as well as natural and other man-made disasters. The table below shows what the various signals mean. It would be a good idea to memorise them.

Click on the "Play" button of the different types of Public Warning Signals to hear how it sounds

Signals How It Sounds* Situation What It Means
"Alarm " Signal This is sounded when an air raid or shelling is imminent. Move to a shelter immediately.
"All Clear " Signal This is sounded when the threat is over. You can leave the shelter.
"Important Message " Signal This is sounded to alert the population to an important broadcast on the radio. Tune in immediately to any local FM radio station or TV channel.

 

Annual Island-wide PWS Sounding

Annually, the SCDF will be sounding the "Important Message" signal through the island-wide network of PWS sirens on 15 February and 15 September at 6:20pm. For the first time, to mark the start of the Exercise SG Ready, the PWS will sound the "Important Message" signal on 1 February 2026 at 3pm, instead of 15 February this year, as a reminder to the public of the need to always be ready for crises and disruptions. This is a one-off change this year and the PWS will continue to sound on Total Defence Day, on 15 February at 6:20pm in the following years.

Do not be alarmed by the minute-long sounding exercise. The signal will also sound for 20 seconds on all smartphones that have the SGSecure mobile app. This will be accompanied by a brief text message on the PWS sounding. To receive the signal and the text message, the app's notification and alert settings must be enabled.

When you hear the "Important Message" signal, tune in immediately to any local radio stations or free-to-air TV channels for a Total Defence Message.

The annual sounding and broadcast message are part of the SCDF's continuous efforts to familiarise the public with the PWS signals and to raise awareness on how the public should react upon hearing the signal.

Should the public have any queries on the sounding, call the SCDF hotline at 1800 367 7233.

SGSecure for Iphone users


SGSecure for Android users

Contact us for more public education materials on the Public Warning System.