What guidance does NFPA provide for automatic sprinkler system water supplies?

April 11, 2024

by Nils Deacon, Manager, Inspections and Rating Services

The most common method of water supply for automatic sprinkler systems is connection to a city or municipal main. The main must be the same size or larger than the sprinkler riser it is connected to. This is primarily for pipe schedule systems. (NFPA 13)

Additionally, if microbiologically influenced corrosion (MIC) conditions are detected, a water treatment plan and system should be installed. Over time, MIC can cause scaling in the pipes of the automatic sprinkler system and may reduce efficiency. This means that less water at lower pressure is available to fight a fire.

Other measures would be to install piping that is corrosion resistant and implement a plan to monitor the piping. This could include regular inspections of the piping, often utilizing fiber optic equipment.

DISCLAIMER: This information reflects the interpretation of MSO, Inc. with regard to NFPA Standards and Codes. It does not represent NFPA’s official position on the items discussed.

MIC scaling in sprinkler piping.