Clean Dirty, Discolored, or Oiled Sprinklers?

1/14/2021

My question is when the discussion of dirty sprinkler heads comes up I get told only lint , hair and fuss count.

What I see quite often is discoloring from what I assume oil running down the pipe to the head. I also often see the red glass turned to black or gray.

Do these sprinklers need to be cleaned, and if so, how is it done?

Air or vacuumed doesn’t always work.

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5 Comments

Dan Wilder

1/14/2021 08:31:14 am

NFPA 25 Annex has some language about these specific questions.

Firstly, NFPA heavily leans towards cleaning sprinklers via positive or negative air flow (compressed air or a vacuum) but shy's away from physically touching the sprinkler during the process.

Impact to sprinklers distribution pattern or the fusing elements (Link or glass bulb) is the main reason to write up sprinklers for being loaded or corroded and trigger NFPA 25 required replacement.

In your examples:
-Oil running down the pipe/fittings then transferring to the sprinkler (assuming this does not congeal and is liquid in nature and is not actively leaking), IMO, would not be a reason to write up a sprinkler and is likely a install concern about excess cutting oil not being cleaned up. It would be a good idea to provide this in a separate recommendation sheet as this liquid could be a base medium for other materials to catch onto and create an issue in the future.

Discoloration of glass bulbs is a continued topic for discussion but per 25, NFPA responses, and a letter you can get from manufactures, loss of color but still having the ability to identify the temperature (via markings on the frame/deflector) does not require sprinkler replacement. Glass bulbs in cold weather will lose their color but will come back when warmed, sprinklers near some fluorescent lights will dull or lose color completely are two specific areas I have seen this occur.

Loss of color vs loss of fluid is an important distinction because the later is a deficiency within 25.

https://www.nfpa.org/News-and-Research/Publications-and-media/NFPA-Journal/2019/March-April-2019/In-Compliance/NFPA-13

Alex Jenness

1/14/2021 09:16:54 am

As an AHJ inspector I would require replacement of a head with a discolored bulb, unless it's been exposed to sunlight or cold and considered okay (NFPA 25 A.5.2.1.1.1). For loading, if a manufacturer has an approved cleaning method, I'm okay with that. Oils on the bulb are concerning as they may absorb heat differently, or insulate the bulb and cause pre-mature or failure to activate.

The annex also says that you can test a sample of heads with limited loading. That seems like more of a hassle than just replacing the heads.

Jim Auer

1/14/2021 09:39:58 am

Agreed with comments above from Dan. The only option given to clean is compressed air or vacuum. My interpretation/understanding is that once the sprinkler is installed... Don't touch it.

NFPA 25 -Any sprinkler that shows signs of any leakage, corrosion deemed detrimental to performance, physical damage, loss of fluid in glass bulb element, loading with dust/foreign debris deemed detrimental to performance or paint other than applied by manufacturer shall be replaced.

Other than obvious damage to sprinklers, who is will to stick their neck out liability wise to say when it's detrimental or not? I've seen AHJs see a speck of paint on a sprinkler and deemed it detrimental and needs to be replaced.

Another common issue is grease buildup on kitchen heads. Swap them out...

Ryan Grant

1/14/2021 04:08:41 pm

I would always consult the AHJ. But as an inspector, if that head has oil on it it would be deemed needing replaced. Like Alex, if the bulb is discoIored, I would also order that head replaced.

Felipe Pedraza

1/14/2021 04:17:52 pm

This is a good concern. NFPA 25 does provide language regarding the cleaning of sprinkler heads and how it should be done.

Basically, if you have oil or an oil like substance coming down from above we need to consider where could this be coming from. We know that their is always some remaining oil on the pipe after threading and assembling. As a former AHJ, I would recommend replacement of the head since some cleaning agents may have a negative with the sprinkler protecting coating which may lead to corrosion or sprinkler failure.

Also, you may someone cleaning the sprinkler and have an accident activation which in turn also leading to a sprinkler replacement and possibly additional expenses.

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