Dry riser

A dry riser inlet box at Park Street Car Park in Cambridge, United Kingdom.

A dry riser is a main vertical pipe intended to distribute water to multiple levels of a building or structure as a component of the fire suppression systems. The pipe is maintained empty of water. The dry riser is the opposite of a "wet riser" or "wet standpipe" system where the pipes are kept full of water for manual or automatic fire fighting operations. Dry risers have to have fire engine access within 18m of the dry riser inlet box. (In the UK they are controlled by the Building (Minimum Standards) Regulations 2000. Dry Risers in occupied buildings have to be within a fire resistant shaft, usually one of a building's fire escape staircase enclosures.) Depending on regional nomenclature, this may refer to a standpipe, intended to provide water to hose connections, or could refer to a vertical main pipe in an automatic dry pipe fire sprinkler system.

A dry standpipe includes a fire department connection which is an external access point at ground level through which water can be pumped from the fire department's fire engine pump to firefighters' hose attachments on each floor.

Dry Pipe Fire Sprinkler System

A dry pipe fire sprinkler system is one in which pipes are filled with pressurized air, rather than water. This air holds a remote valve, known as a dry pipe valve, in a closed position. Located in a heated space, the dry-pipe valve prevents water from entering the pipe until a fire causes one or more sprinklers to operate. Once this happens, the air escapes and the dry pipe valve releases. Water then enters the pipe, flowing through open sprinklers onto the fire.

References

See also

• Fire fighting
• Fire sprinkler
• Fire sprinkler system
• Dry Standpipe
• Siamese connection