By Alyssa Dunn, General Manager, Dyne Fire Protection Labs
According to NFPA 25, the Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, sprinklers are to either be replaced or tested at periodic intervals. If testing, a minimum of 4 sprinklers or 1% of the sprinklers per sample area should be submitted to a laboratory for field service testing.
5.3.1.2 A representative sample of sprinklers for testing in accordance with 5.3.1.1 shall consist of either a minimum of four sprinklers or 1 percent of the number of sprinklers per sample area, whichever is greater.
Defining the sample area is a critical step in the testing process. NFPA 25 doesn’t define the term sample area which can leave room for confusion. However, this allows building owners and/or their designated representatives to define their sample areas. When defining sample areas, it is important to keep in mind that if one sprinkler fails to meet the testing requirements, ALL the sprinklers within that sample area shall be replaced. Therefore, it can be advantageous to define sample areas by environment and group sprinklers together that are exposed to similar environmental conditions.
5.3.1.3 Where one sprinkler within a representative sample fails to meet the test requirement, all sprinklers within the area represented by that sample shall be replaced.
For example, consider a building with an office space, a parking garage, and a swimming pool. One option is to define the sample area as the whole building. A representative sample of 4 or 1% of the sprinklers, whichever is greater, should be submitted for testing. However, if one of the sprinklers fails – ALL the sprinklers in the whole building would need to be replaced. In this example, one of the sprinklers from the pool area fails. Because the sample area was defined as the whole building, every sprinkler would need to be replaced.
Take the same building with the office space, parking garage, and swimming pool. In this example, the sample areas are defined by their environment so there are three separate sample areas – office space, parking garage, and pool area. A minimum of 4 sprinklers or 1%, whichever is greater, should be taken from each sample area. Again, one of the sprinklers from the pool area fails the field service test. In this example, only the sprinklers in the pool area would need to be replaced. This example may require the sampling of more sprinklers compared to the first example, but now only one of the sample areas needs replacement instead of the whole building.
If environmental conditions are similar, sample areas could also be defined by floor, riser, system, building, etc. It is ultimately up to the building owner and/or designated representative to define the sample area(s). Regardless of how the sample areas are defined, it is important to do so as it can greatly impact if and how many sprinklers need to be replaced.
Questions? Contact us today by calling (800) 632-2304 or emailing dyne.lab@nfpaglobal.com.
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