sprinklernotes
Residential Dryer as a Heat Source “We have an apartment building project where the local fire inspector is requiring that we replace the 155degree pendent heads near the dryer in the unit with 200-degree sprinklers. These dryers sit in a little alcove with no doors on it. The heads are in the 8-ft ceiling and vary from about 18 in. to 5 ft horizontally from the face of the dryer. Do ordinary-temperature sprinklers need to be replaced with the intermediatetemperature sprinklers?”
We have reviewed NFPA 13, Standard for the Installation of Sprinkler Systems, 2016 edition as the applicable standard. Our informal interpretation is that the ordinary-temperature rated sprinklers can remain in place. Section 8.3.2.4 indicates that sprinklers of intermediate- and high-temperature classifications shall be installed in specific locations as required by section 8.3.2.5. This section refers to Table 8.3.2.5(c) Temperature Ratings of Sprinklers in Specified Residential Areas. This table does not specifically list clothes dryers. The table does identify kitchen ranges and wall ovens where ordinary-temperature-rated sprinklers need to be at least 18 in. away. A residential dryer produces a lot less heat than these sources. In addition, it would be the same for stackable washer/dryer units. As such, this application meets the intent of the standard. There is heat from the dryer, but it should dissipate before it would activate a sprinkler. The table does identify heat sources from the side of ceiling- or wall-mounted hot air diffusers need to be 24 in. away and the front of wall-mounted hot air diffusers needs to be 36 in. away. These are forced air sources where the heat discharges further distances where these minimum distances would not apply to this application. An alternative approach is to install intermediate-temperature-rated sprinklers throughout per section 8.3.2.1. This can help avoid placing sprinklers too close to specific heat sources.
