IMO signs explained

With this article, we intend to initiate a series of articles that will look into a particular IMO symbol and based on the relevant standard to describe the meaning behind its graphical components as well as to describe the firefighting or lifesaving equipment each particular symbol is supposed to identify.

In this series of articles the first sign to be featured is the Fire Hydrant sign:

Each vessel is fitted with portable marine firefighting equipment and with fixed firefighting installations. The selection of equipment used to fight a specific fire will depend on the intensity and type of fire. The fixed installation is used when the fire cannot be fought and restrained by portable equipment. A vessel’s main fixed firefighting installation is comprised of several strategically located fire hydrants and with a series of dedicated pumps that supply them.
 
The fire hydrant symbol is specified by IMO Resolution A.952 (23), ISO 17631 and IMO Resolution A.1116(30). The graphic components of the sign contain the pictogram for this specific equipment, the red color that identifies this equipment as part of a firefighting system, and the green color in combination with the "W” to identify the extinguishing media and provide information to the used of what type of fires this can be used on.

When identified with this high luminance photoluminescent sign the firefighting team will be able to quickly locate the fire hydrants, even in a black out situation, and to start tackling the fire immediately upon its discovery.