#71 – When to Replace Fire Sprinkler Heads in a Fire Sprinkler System?

All fire sprinkler heads require regular inspection, and very old, damaged, or otherwise impaired fire sprinklers must be replaced

Fire sprinkler systems are known for their longevity. In most cases, their lifespans are comparable to the buildings in which they are found. But because fire sprinkler heads remain idle unless there’s an emergency, it can be difficult to identify subtle, age-related problems with them. Unless an issue is highly visible — like a leak or corrosion — it may go unnoticed.

Performing regular inspections, testing, and maintenance helps ensure sprinklers work well for decades. But at some point, even highly reliable heads must be replaced. This blog will help you identify the age of your fire sprinkler heads and explain when they must be tested or replaced.

Need to replace your fire sprinkler heads right away? Feel free to jump on over and check out our selection of commercial fire sprinklers.

How do I determine the age of fire sprinklers in a system?

To figure out the age of the fire sprinklers in a system, begin by looking at building documentation and other pertinent information. In the best-case scenario, there are clear records of the building’s completion and system installation, renovations, and/or upgrades, including any changes to the sprinklers within the system.

Often, people first examine the supply of required spare sprinkler heads in the fire sprinkler head replacement cabinet. Their reasoning is that, in theory, these sprinklers are the same age as those installed in the system. However, if any spares have been used and replaced over the years, they may not match the age of those within the system. This is where it gets a bit tricky — and why you should not rely on this method alone.

When do I perform a fire sprinkler inspection?

NFPA 25 requires visual fire sprinkler inspections by qualified personnel, often a fire protection contractor, on an annual basis.

From the 2023 Edition of NFPA 25* Sprinklers shall be inspected from the floor level annually.

NFPA does allow some exceptions to this rule:

From the 2023 Edition of NFPA 25* Sprinklers installed in concealed spaces such as above suspended ceilings shall not require inspection. Sprinklers installed in areas that are inaccessible for safety considerations due to process operations shall be inspected during each scheduled shutdown.

A man inspects a fire sprinkler.
An inspector looks at a fire sprinkler head “from the floor level.” Image source: Cintas

Quarterly visual inspections of sprinklers, while not required, can be beneficial and are often conducted by qualified facility managers and maintenance personnel. It’s best to form a routine and remain consistent, as this creates a familiarity with the sprinklers and makes it easy to spot any changes or potential problems. It’s also important to keep a record of all inspections. Doing so also creates a record of any issues that arise and actions that are taken, helping maintain the overall health of the system.

Service providers may or may not use forms to conduct annual inspections that are considered acceptable to all Authorities Having Jurisdiction (AHJ). It’s up to a building owner, facilities manager, etc. to verify that the forms are sufficient and that inspections meet NFPA 25 criteria.

Here’s what inspectors are looking for, with each issue indicating that a sprinkler must be replaced:

From the 2023 Edition of NFPA 25* Any sprinklers that show signs of any of the following 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, detrimental to sprinkler performance

The 2023 edition of NFPA 25 loosened the rules for painted sprinklers a bit with the words “detrimental to sprinkler performance,” whereas the 2017 edition did the same for loading and corrosion. You can read about the change and what’s considered “detrimental” in this blog.

When do I perform age-related fire sprinkler testing?

Unlike many other system components, heads have a very long testing interval based on the age and type of sprinklers within the system.

This testing frequency increases over time as they age and the initial test is based on their installation date. If the date of installation is unidentifiable, the manufacture date of the fire sprinkler heads may be used instead (though their manufacture date may predate the system). Prior to any testing, a visual inspection must look for any obvious defects:

From the 2023 Edition of NFPA 25

A. Sprinklers should be first given a visual inspection in accordance with to determine if replacement is required. Sprinklers that have passed the visual inspection should then be laboratory tested for sensitivity and functionality. The waterway should clear when sensitivity and functionality is tested at 7 psi (0.5 bar) or the minimum listed operating pressure for dry sprinklers.

Until the 50-year mark, it’s not necessary to test standard response sprinkler heads that aren’t installed in harsh environments. But because fast-response sprinklers have only been around since about 1980, their lifespans and failure rates are still less well-known. Thus, NFPA 25 requires first testing them at 20 years rather than 50. Here are the testing intervals for various types of sprinklers:

From the 2023 Edition of NFPA 25

Type Frequency Reference
Standard Response Sprinklers At 50 years and every 10 years thereafter
Standard Response Sprinklers first tested at 75 years At 75 years and every 5 years thereafter
Dry Sprinklers At 20 years and every 10 years thereafter
Solder-Type Extra-, Very Extra-, and Ultra-High-Temp. Sprinklers (consistently used in hot environments) Tested every 5 years*
Fast Response Sprinklers (except ESFR and CMSA sprinklers) At 25 years and every 10 years thereafter*
Early suppression, fast response (ESFR) & control-mode special application (CMSA) sprinklers At 20 years and every 10 years thereafter*
Sprinklers used in harsh environments, including corrosive atmospheres, as defined by A. Tested every 5 years*
Listed corrosion-resistant sprinklers used in harsh environments Tested every 10 years and every 5 years thereafter

As shown in the table, special types of fire sprinklers and those subjected to harsh environments have a much shorter span between testing periods. Older types of dry sprinklers, for example, had a 50 percent failure rate after they reached the 10-year mark, according to NFPA. But later data indicated that newer models had solved some of these problems, so NFPA incrementally increased the initial testing interval by 5 years in the last three editions. Read more about these changes and testing in our blog: “Fire Sprinkler Testing Procedures & Replacement in NFPA 25.”

Testing is not necessary for the full set of sprinkler heads within the system, but rather for a representative sample.

From the 2023 Edition of NFPA 25* Where required by Section 5.3, sample sprinklers shall be submitted to an approved testing laboratory for field service testing.* A representative sample of sprinklers for testing in accordance with shall consist of either a minimum of four sprinklers or 1 percent of the number of sprinklers per sample area, whichever is greater.

A representative sample means that sprinklers should not be selected solely on their ease of access. A fire protection professional who follows best practices takes a random sample from different floors, rooms, and areas within the facility. When selecting a sample set, they should pick sprinklers of different types and from different environments.

The sample set must undergo a plunge test. Using the controlled plunge test apparatus, the sprinkler is pressurized with 5 psi (0.4 bar) of air pressure. The test measures the amount of time it takes the heat-sensitive element to activate. When a fire sprinkler head from a sample set fails to activate in the appropriate amount of time during the plunge test, it’s necessary to replace all sprinklers within the system or just the area the sample represents (if multiple samples were taken).

Again, you can read more about testing procedures, sampling scenarios, and more in our detailed blog on the subject.

When do I need to replace old fire sprinkler heads?

As mentioned earlier, any sprinkler that fails a visual inspection from the floor level must be replaced immediately. So do sprinklers “affected by a fire as determined by the AHJ.” When it comes to old sprinklers, samples that are tested and fail a plunge test indicate that every sprinkler in the system or an area of the system represented by a sample must be replaced. And all fire sprinklers manufactured before 1920 must be replaced. These four rules are consolidated in section of NFPA 25 (2023).

Because sprinklers fail more as they age, and installing new sprinklers significantly increases the time until the next testing interval, replacement might be a better option rather than continuing to test old sprinklers periodically. It could be helpful to weigh the costs of testing in comparison to purchasing new heads to determine the best plan.

Tips for avoiding early replacement

Remember, sprinklers with “loading detrimental to sprinkler performance” must be replaced if an inspection spots them. Heads that are “heavily loaded” have dust, dirt, debris, or grease that is difficult to remove without touching the sprinkler head. Before you resort to a replacement, you can try a touch-free method of cleaning dirty fire sprinkler heads. Nevertheless, if you find it would be necessary to wipe or scrub sprinklers with a cleaning solution, then you need to replace them.

A dust-covered, or loaded, fire sprinkler head.
A dirty or “loaded” fire sprinkler head.

Never, under any circumstances, paint fire sprinklers (or cover plates). If a fire sprinkler head has been painted in a way that’s detrimental to performance, it needs to be replaced by a sprinkler with the same characteristics. Painting sprinkler heads can cause irreparable damage that causes them to activate late or otherwise malfunction.

It goes without saying that leaking or physical damage can hinder the proper operation of a fire sprinkler head. Leaking or damaged heads must be replaced as soon as possible, which is why NFPA 25 mandates having a specific number of spare sprinklers onsite that depends on the size of the system. These spares should be placed in a fire sprinkler cabinet, along with the wrenches needed to install them.

A corrosion-damaged fire sprinkler head.
A fire sprinkler head that’s badly damaged by corrosion. Image source: Garden Grove Water Damage

If you’re looking to replace fire sprinkler heads, consider purchasing from QRFS! We offer a wide variety of commercial and residential fire sprinklers from Viking, Victaulic, Tyco, Reliable, and Senju. Regardless of whether your job needs one head or hundreds, we’ve got them in stock and ready to ship!

When you purchase from QRFS, you benefit from our quality customer service and extensive product knowledge. We stay up-to-date on codes, standards, and industry best practices so that we can provide you with the right information at the right time.

Click here to browse our selection of commercial fire sprinkler heads.

More questions? Reach out to us by calling +1 (888) 361-6662 or emailing support@qrfs.com.


This blog was originally posted by Jason Hugo and Anna Hartenbach at blog.qrfs.com on August 24, 2017, and updated on February 5, 2023. If you found this article helpful, check us out at Facebook.com/QuickResponseFireSupply or on Twitter @QuickResponseFS.

29 thoughts on “#71 – When to Replace Fire Sprinkler Heads in a Fire Sprinkler System?”

    • Color changes in the liquid-filled bulbs (specifically, loss and return of color) can happen in cold (loss) and warm (return) temperatures, respectively, without necessarily impacting sprinkler performance. But you should check with a qualified fire sprinkler professional to determine if this is the issue—and whether the heat-sensitive liquid is present and the sprinkler will function as intended. You should also ensure that you have the correct color for the intended temperature rating of the sprinkler.

  1. What kind of corrosion resistant fire protection sprinkler heads should I purchase for the 15 or so located inside each unit of my High rise condominium located in the Florida gulf coast? We seem to have more than our share of corrosion of sprinkler head elements.

    • Jim — There are several corrosion-resistant coatings or finishes that may work in your situation, including Polyester paints, Electroless nickel (ENT), PTFE (“Teflon”), and Electroless nickel-PTFE. But the exact sprinkler model and type will depend on whether it is a residential NFPA 13D/13R sprinkler system or a commercial 13D system, along with the specific characteristics needed for the heads. You can learn more by reading this blog. Otherwise, we can have QRFS customer support reach out to you to get specifics or you can email them here. Thanks for reading!

  2. Hello: I have recently upgraded an older inefficient gas fireplace to a new gas fireplace that has a warm air vent near the ceiling. There is a fire sprinkler about 5’ directly in front. The ceiling temperature measured at 125f with the fireplace on its lowest setting. Will it be possible to replace the existing sprinkler head to something with a higher rating? Thanks, Andy.

    • Andy — First, thanks for reading. NFPA 13 has a dedicated table that explains which temperature ratings can be used at what distances from certain heat sources, but we’d be remiss if we provided a recommendation online without knowing more about the situation. We recommend you consult with a qualified fire protection professional in your area. You can also try our Ask a Fire Pro service to get some general advice; click the link to submit your question with some information about your building or system, and a fire protection pro will provide a detailed answer based on standards and codes. Our pros include AHJs, contractors, engineers, and code experts with 150+ years of combined experience!

  3. We hive in a community of 488 condo units in SW FL. A company inspected all units and said we have to replace 1850 sprinkler heads. This seems excessive, I understand the replacement rules, but does 1 speck of paint on the sprinkler head require replacement? I’m not talking about a head that has been “painted” but a speck of overspray.

    • John — Unfortunately, any paint anywhere on the frame, heat-sensitive element, deflector, or any other part of the sprinkler is considered a cause for replacement per NFPA 25 or 13. You might consider speaking with your local AHJ (fire marshal), however, to discuss their interpretation of the rules—but NFPA scope is pretty broad on any paint equaling replacement. You may consider the contractor’s estimate for the heads themselves and whether buying the parts directly is a cheaper option.

  4. I’m on the board of a 157 unit condo community. Our sprinkler heads are about 30 years old. We are replacing sprinkler heads in exterior storage closets attached to each unit. It has been said that we can count on failing our test and that all the interior sprinkler heads need to be replaced, which, in my home, are 6 heads. Do we need to cut out the drywall in order to do this? This just seems very inconvenient, messy and it is expensive. However, we keep reminding ourselves about the failure in Florida.

    • Hey Janet — Replacing sprinklers does require some work, and if the sprinklers are fast response (likely, since this is a residential setting), they do need to be replaced after the first 20 years after installation and every 10 years thereafter. Whether or not you need to cut out drywall depends on how they were installed but it is very possible. Sprinklers must be replaced by a qualified fire protection professional, of course, and that pro will be able to determine the best, minimally invasive option. Best of luck — and if you have the potential to save on the parts with QRFS, feel free to browse our selection and email or call us with any questions.

  5. Hi, I have to replace old fire sprinkler heads for my complex. According to my contractor I have quick response red bulbs and my contractor told me they expired this year. I installed them 20 years ago. Are there other non quick response heads I can install for my apartments that will last longer than 20 years before having to test them?

    • Raul — are there other heads that might work with longer testing or replacement intervals? The short, highly caveated answer — because it all depends on the system and its design — is “possibly but not likely.” Quick response heads are the go-to sprinklers for light-hazard settings, which include apartment complexes. Their unique design prioritizes earlier activation to give people time to escape, thus saving lives.

      Note, however, that replacing all of the sprinklers is only one option — you can also just contract with a fire protection pro who will remove a sample of them to send for testing that makes sure they still work. Best of luck!

  6. Hi, my name is hazem , from Egypt , I have a question regarding sprinklers lifetime that still stored without installation ( storing in a good condition & no change for brass color ..etc).

    For example, I have stock from different sprinklers type ( manufacturing dates are 2009 , 2014, 2015 ), to be used from time to time in new construction projects. Someone told me that , the old manufacturing sprinklers like stored, it becomes old , and not recommended to use.

    My question is there any lifetime for stored sprinklers under good condition? and reference please, if any.


    • Hazem — Section 5.3 of NFPA 25 (2023 edition) covers the latest on long-term testing and replacement, and it does not have any specific prescriptions for non-installed, spare sprinklers. The only mention of spares in that section that we’re aware of is that NFPA 25 says you CANNOT submit any of the spare sprinklers for testing in a testing sample; this indicates that non-installed sprinklers are LESS likely to go bad, and NFPA 25 doesn’t want that factor to influence the test. Further, spare sprinklers are usually stored in a protected cabinet and away from heat and corrosion sources.

      Thus, we can’t provide any specific info on spare sprinkler replacement. But if you look at the timelines for testing or replacing sprinklers that ARE installed and MORE likely to go bad, the intervals are 50, 25, and 20 years for the most common different sprinkler types — unless they are in harsh/corrosive environments (every 5 or 10 years). Thus, it stands to reason that your spare sprinklers should be fine, subject to the visual inspection in section — but contact your local authority having jurisdiction to see what they say!

  7. What if the sprinklers are very high and the age cant be read? Do we assume they need to be replaced based on building age? Or do they get a pass because they can’t be seen from the floor?

    • Tommy — A reasonable interpretation of the standard is that the visual inspection rules apply to the six-point list of visibly identifiable conditions (leakage, corrosion, loading, etc.) that show a sprinkler may be impaired. The age of the sprinklers is something an owner or designated representative should know regardless of an annual visual inspection. So, it is not a good idea to assume that very old sprinklers requiring functionality testing or replacement “get a pass” based on their height from the floor level.

      Strategies for determining sprinkler age include reviewing system design documents (if available), looking at the sprinklers and lists of them in the spare sprinkler cabinet (required by NFPA 25), and otherwise, yes, trying to figure out their age based on the age of the building, system, and inspection, testing, and maintenance records. You should engage a qualified fire sprinkler professional to assess the age and potential need for testing or replacement if you believe the sprinklers might be old enough to merit action.

  8. Back when working as a Fire Safety Tech… I had read that the glass bulb sprinkler heads were only rated for 10 yrs. However, now I don’t see a firm rule for that. (I know when you really walk down a facility, all the heads will be the same manufacturer and year, except for one.) Please let me know if: glass => 10 yr. – or it is indeed the 6 point inspection criteria!

    • Jason — we are unaware of a global lifespan like that for ‘glass-bulb sprinklers.’ The 6-point rule always applies and was recently updated in the latest edition of NFPA 25 (read about that here). The only 10-year rules we are aware of is a previous (now outdated) initial testing and/or replacement rule for dry sprinklers, a current one for corrosion-resistant sprinklers in very harsh/corrosive environments, and retesting and/or replacing rule for most standard sprinklers after they hit 50 years old and every 10 years after that. As a rule, glass-bulb sprinklers are designed to last a lot longer than a decade. Here’s a summary of the latest and greatest testing and replacement rules in NFPA 25.

  9. My building has Grinnell SSU-1 TYPE B with a G in the center of a triagle. Can you tell me the year and K factor for this sprinkler head?

    • Jeff — This is a tough one, as Tyco bought Grinnell in 1970 and many Grinnell sprinklers are pretty old—for example, this Type B “Duraspeed” is from 19345. “SSU” indicates it’s an upright (standard spray upright). Without knowing more about the specific model and what it looks like, we can’t definitively ID that in this forum from your description.

      Two options:

      1. If you’re looking for a replacement sprinkler, email support@qrfs.com with several close-up pictures of the head (sides and one or two close-ups of the deflector; close enough to review all lettering on the deflector and frame). We can research a suitable replacement (and it will have to be a different sprinkler model (likely Tyco), as this one is obsolete).

      2. You can go straight to the source and contact Tyco tech support directly, as they bought Grinnell and still oversee the old catalog:


      Option 2
      Option 4 (“Water”)


  10. In the event of a fire where multiple sprinkler heads have been activated, is there any requirement for replacing unactivated sprinkler heads within a certain distance of the activated ones??

    • Joe — There are no explicit “distances” regarding the scenario you describe that we’re aware of, but there is item (4) in section of NFPA 25 (2023 edition): Replacement Sprinklers.

      Sprinklers with any of the following qualifications shall be replaced: […]

      (4)* Sprinklers affected by a fire as determined by the AHJ.

      The appendix clarifies when nearby, non-activated sprinklers may need to be replaced (our emphasis added):


      In the event of a fire, all sprinklers within the fire area should be inspected after the incident. In situations where the fire was quickly controlled or extinguished by one or two sprinklers, it might be necessary only to replace the activated sprinklers. Replacement sprinklers should be of the same make and model or have compatible performance characteristics (see Soot-covered sprinklers should be replaced because deposits can result in the corrosion of operating parts. In the event of a substantial fire, special consideration should be given to also replacing the first ring of sprinklers surrounding the activated sprinklers due to the potential for excessive thermal exposure, which could weaken the response mechanisms.

      Hope that helps, and thanks for reading!

      • Do you have to replace the piping to or only the heads when you have soot on them? Can you only clean the piping?

        • Terry — Chapter 5 of NFPA 25 only details replacing the heads if they are “loaded” (e.g., with soot), if the loading cannot be cleaned w/o touching the sprinkler (e.g., with compressed air) and its detrimental to sprinkler performance.(Section, 2023 edition) NFPA has no explicit sections on replacing or rules for cleaning dirty pipe; the concerns with pipes and fittings are they must be “free of mechanical damage, leakage, and corrosion.” (Section, 2023 edition)

          However, some cleaning substances are incompatible with CPVC pipe, for example. You should contact a local inspection, testing, and maintenance pro, and they can assess your situation!

  11. I have a customer with a warehouse that has 5.6k ssu sprinklers from 1936 that have never been tested. Is there guidance on testing after 88 years, or do they all need to be replaced?

    • Brian — The interval generally depends on the sprinkler type, but those are so old they likely fall under this rule in NFPA 25 (2023): Where sprinklers have been installed for 50 years, one of the following shall occur:

      (1) The sprinklers shall be replaced.
      (2) Representative samples of the sprinklers shall be tested and then retested every 10 years.

      If they have been manufactured before 1920, they simply need to be replaced.

      You can learn more about the rules in our other, newer blog, and you should consult a fire protection pro (fire inspector and/or contractor) in your area to get a definitive answer and course of action. Thanks for reading!


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