Testing Requirements for Backflow Preventers

Q: Many AHJ’s are requiring RPZ backflow devices on sprinkler systems. Is there a testing requirement for these devices? Also, is there a periodic test required for a PIV?

A: Yes, backflow preventers, both double-check and reduced pressure zone (RPZ) type must be tested on an annual basis when connected to sprinkler systems. Sections 9-6.2.1 and 9-6.2.2 NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems (1998 edition), require all backflow preventers installed in fire protection system piping to be tested annually at the designed flow rate of the fire protection system in accordance with the following:

  • A forward flow test must be conducted at the system demand, including hose stream demand, where hydrants or inside hose stations are located downstream of the backflow preventer;
  • A backflow preventer performance test, as required by the authority having jurisdiction, shall be conducted at the completion of the forward flow test.

Post Indicator Valves (PIV) are control valves, and according to section 9-3.3.1, 9-3.4.1 and 9-3.4.3 of NFPA 25, the must be tested and inspected as follows:

  • Monthly inspections
  • Semi-annual tamper switch test
  • Annual exercise, whereby the valve is fully closed and then fully opened.

And, in case you were not aware, section 9-3.4.2 of NFPA 25 requires a main drain test to be conducted downstream of any valve that is closed and then re-opened for any reason. So it is best that you coordinate the annual main drain test right after the annual control valve exercise.