http://www.scdf.gov.sg/Community_an...l_Defence/War_Time_Emergencies/wartime06.html
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Public Warning System
</TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2>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 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.
</TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2> </TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2><TABLE borderColor=#cccccc width="100%" summary="This table provides contact info on PWS" border=1><TBODY><TR class=tableheader><TH width="26%">Signals</TH><TH width="25%">How It Sounds*</TH><TH width="26%">Situation</TH><TH width="23%">What It Means </TH></TR><TR class=tablecontent vAlign=top><TD>
"Alarm" Signal</TD><TD>
</TD><TD>This is sounded when an air raid or shelling is imminent.</TD><TD>Move to a shelter
immediately.</TD></TR><TR class=tablecontent vAlign=top><TD>
"All Clear" Signal</TD><TD>
</TD><TD>This is sounded when the threat is over.</TD><TD>You can leave the shelter.</TD></TR><TR class=tablecontent vAlign=top><TD>
"Important Message" Signal</TD><TD>
</TD><TD>This is sounded to alert the population to an important
broadcast on the radio.</TD><TD>Tune in immediately to any local FM radio station.</TD></TR></TBODY></TABLE></TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2>
*Click on image to hear the signal
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NOTE:
To hear the audio recording of the various Public Warning Signals, click "How it Sounds" in table above. To find out more about the system, you may call the SCDF Hotline at 1800-286-5555.</TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2> </TD><TD> </TD></TR><TR><TD> </TD><TD colSpan=2>
Contact us for more public education materials on the Public Warning System.
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FAQs on Public Warning System
Find out what are the
commonly asked questions on Public Warning System.
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