15 Jul '11, 11am
Look, the SCDF has a page about the Deathly Hallows:
To identify a CD Public Shelter, look out for the CD shelter sign. It is a triangular, consisting of a YELLOW background with WHITE CD letters on black triangle. The word "Shelter" is marked in BLACK letters on the YELLOW background below the BLACK triangle. This sign denotes a civil defence public shelter. You will see it near or at the places where the shelters are located.