in recent editions of NFPA 25, the requirements for no-flow (churn) test frequencies have changed for electric motor driven fire pumps (only). Diesel engine driven fire pumps have always been required to run weekly for 30 minutes. This allows the engine to establish a running speed and confirm that no problems exist such as overheating or lack of combustion air for the engine. As always, it is best to observe problems during periodic testing than to discover them forensically after a catastrophic event. Running the diesel engine weekly for 30 minutes also consumes some of the diesel fuel, which is susceptible to deterioration over time.

It bears noting that NFPA 25 (the Standard for Inspection, Testing & Maintenance Requirements for Water-Based Fire Protection Systems) does not have a retroactivity clause, so unless you are in a state where there is a specific edition (year) adopted, the most current edition is the version we will be inspecting to.

Section 8.3.1.2* requires a no-flow test to be conducted weekly for electric motor–driven fire pumps:

• Serving fire protection systems in buildings that are beyond the pumping capacity of the fire department
• Fire pumps with limited service controllers
• Vertical turbine fire pumps
• Fire pumps taking suction from ground level tanks or a water source that does not provide sufficient pressure to be of material value without the pump

Section 8.3.1.2.2 allows a monthly test frequency electric fire pumps not identified in the list above and for electric fire pump systems having a redundant fire pump. In all cases, the electric motor should be allowed to run for a minimum of 10 minutes and a qualified person should always be present in the pump room whenever any fire pump(s) are running to make observations related to operating issues and to record results.

Fire pumps are critical parts of your fire protection system(s) as they provide the water supply volume and pressure needed for your water-based system to control or suppress a fire