Water Supply Industry Interpretations and Advice

  • Area of Interest : Backflow prevention
  • Topic : Fire sprinklers
  • Title : Fire sprinkler systems - backflow protection of domestic water supplies
  • Clause Reference : Schedule 2 paragraph 15 & G15.3
  • Reference Number : B18
  • Decision Date : February 2002 (Revised October 2011)

Fire sprinkler systems which do not contain additives only:

A backflow prevention arrangement rated to at least fluid category 2 (e.g. an approved single check valve) must be installed on all branches connecting fire sprinkler systems to a supply or distributing pipe conveying water to be used for domestic purposes (i.e. water used for drinking, bathing, cooking or washing.). The backflow prevention arrangement should be installed on the fire sprinkler pipework as close as is reasonably practicable to the point(s) of connection to the supply or distributing pipe.

Fire sprinkler systems using additives are classified as a fluid category 4 risk, and the appropriate backflow protection device or arrangement should be provided.