By Grant Lobdell, General Manager

According to the current, 2020 edition of NFPA 25, the Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, sprinklers shall be inspected from the floor level annually ( and any sprinkler that shows any of the following signs shall be replaced (

  1. Leakage
  2. Corrosion detrimental to sprinkler performance
  3. Physical damage
  4. Loss of fluid in the glass bulb heat-responsive element
  5. Loading detrimental to sprinkler performance
  6. Paint other than that applied by the sprinkler manufacturer

This floor level inspection and the replacement of any sprinklers that show any of the signs above should occur before sampling for the routine (Table 1) field service test (A. testing, however, can be done at any time to help determine whether any corrosion and/or loading observed during the floor level inspection is detrimental.

At Dyne Fire Protection Labs, a sprinkler’s appearance is NOT considered as part of the field service evaluation. According to NFPA 25, the field service test is to be an evaluation of a sprinkler’s thermal sensitivity (response time index) and whether the waterway fully clears upon activation (A. As such, any sprinkler* received, regardless of its appearance, will be put through the field service test and evaluation will be made solely on those parameters.

If you have any questions regarding this article, please contact Dyne Fire Protection Labs at or (800) 632-2304.

*Apart from damaged sprinklers that no longer hold pressure.