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    Fire Engine / Ambulance

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    Non-Emergency Ambulance

  • Fire Hazard Reporting

    1800 280 0000

  • General Enquiries

    1800 286 5555

  • 995

    Fire Engine / Ambulance

  • 1777

    Non-Emergency Ambulance

Public Warning System


The Public Warning System (PWS) is a network of sirens that the SCDF has placed at strategic points throughout the island. The purpose of this system is 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. 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 station or TV channel for a two-minute message on the PWS.


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.


SGSecure for Iphone users

PWS Infographics (Iphone)


SG Secure for Android users

PWS Infographics (Android)


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