Published on May 9, 2022.

ITM Updates

Six key proposed changes to the 2023 edition of NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems


As a new homeowner, I have learned that there are many tasks that need to be completed on a regular basis for a home to remain in good working order.

There are weekly chores, such as vacuuming, cleaning bathrooms, and lawn maintenance. There are yearly activities that include chimney inspection and heating and air conditioning system maintenance. Then there are items that need attention less frequently, such as driveway sealing or the replacement of a roof or major appliance.

I’ve also learned about the parts of a new house that you may want to update, such as installing new systems to take advantage of newer technologies: smart appliances and solar panels, for example, or geothermal heating and cooling systems. The new gadgets will need to be accompanied by new maintenance schedules and procedures to keep them in good condition, of course. Call it a newbie’s enthusiasm, but I’m convinced that staying up-to-date on maintenance responsibilities while making gradual improvements can positively contribute to your comfort as well as to the longevity of your home.

The same goes for sprinkler systems. Water-based sprinkler systems also require regular inspection, testing, and maintenance (ITM) to ensure that they remain in proper working order and extend the effective life of these systems. The ITM procedures and standards that govern water-based systems also need to be updated and improved to reflect new data and technologies that can better ensure the functionality of these critical life safety systems. The technical committee for NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, has been updating the standard to ensure that the latest information is available to inspectors performing ITM functions designed to keep these systems ready in case of an emergency. There are a handful of key additions and revisions to the 2023 edition of NFPA 25 that address some of the latest concerns regarding ITM activities.

Addition of foam system requirements

One of the largest proposed changes to the 2023 edition of NFPA 25 concerns Chapter 11 and foam system requirements. In previous editions of NFPA 25, Chapter 11 provided the ITM requirements for foam-water sprinkler systems that were governed by NFPA 16, Standard for the Installation of Foam-Water Sprinkler and Foam-Water Spray Systems. The NFPA 16 standard was withdrawn at the Fall 2020 revision cycle, however, and subsequently incorporated into NFPA 11, Standard for Low-, Medium-, and High-Expansion Foam.

When NFPA 16 and NFPA 11 were combined, the technical committee identified an ITM requirement gap between foam-water sprinkler systems and other foam systems covered under NFPA 11. In conjunction with the NFPA 11 technical committee, a task group was organized by the NFPA 25 technical committee. An entirely new Chapter 11 was created for NFPA 25 and was introduced at the first draft stage. This new chapter retains prior requirements for foam-water sprinkler systems and provides new requirements for the other types of foam systems from NFPA 11. NFPA 25 will now be a one-stop shop for the ITM requirements for water-based and foam fire protection systems.

Need to inspect under concealed cover plates

Another major proposed change to the next edition of NFPA 25 is the requirement that a percentage of concealed cover plates in a sprinkler system be removed every five years to check for hidden issues. This is a significant increase in scope from the type of inspections required in past editions of NFPA 25.

Previously, a typical sprinkler system inspection was limited to a visual inspection from the floor. Removing cover plates would require additional equipment, such as tools and a ladder or lift. Even though this type of inspection would require more work on the part of the inspector, this new requirement is proposed to uncover hidden issues such as leaks, damaged sprinkler heads, or improper cover plate installation. Any of these issues can cause premature operation of a system or cause the system to be ineffective when it does operate.

A certified amending motion has been filed on this proposed requirement that seeks to have it removed from the standard. Some have argued that there is a lack of technical substantiation for this requirement, and that the five-year inspection time frame was arbitrary. It has also been stated that the need for additional tools and ladders or lifts places an unnecessary expense on the inspector. This will be discussed during the technical session at the NFPA Conference & Expo® in June.

Change to testing frequencies for fast-response elements and dry sprinkler heads

For this proposed change, the technical committee has increased the initial time frame for some types of sprinkler heads until they are subject to field service testing by an approved laboratory. Sprinkler heads using fast-response elements—except for early suppression, fast response sprinklers, and control-mode special application sprinklers—will now require testing after they have been installed for 25 years instead of 20, and dry sprinkler heads will need testing after 20 years instead of 15.

Dry sprinklers were first introduced about 30 years ago, and fast-response sprinklers have been around for about 50. When both of these sprinkler types arrived, the frequency of testing was kept low because it was not known how they would perform over time. Now that they have been in place for a while, a history of test data has accumulated to support changing the testing frequency. The newly proposed frequencies are based on UL testing that was completed in 2019, which showed that an extended testing frequency was appropriate. This update changes the standard to align with the latest available data.

Updated antifreeze system requirements

The requirements for antifreeze systems have also been under scrutiny for the past several cycles of NFPA 25 because of the flammability concerns of antifreeze at high concentrations.

Starting with the 2014 edition of NFPA 25, for all systems installed prior to September 30, 2012, there was a sunset date of September 30, 2022, which required all systems to change to a listed antifreeze solution. This sunset date allowed time for manufacturers to create listed antifreeze solutions that meet NFPA 25 requirements. This date is being removed because the effective date of the 2023 edition of NFPA 25 will be after the sunset date, and there are currently listed antifreeze solutions that meet the required conditions. All systems, with few exceptions, will now be required to use a listed antifreeze solution to refill existing systems whose solutions do not meet the required criteria.

It is important for stakeholders to review the antifreeze manufacturer’s data sheets, since the characteristics of listed antifreeze solutions, such as viscosity and specific gravity, do not necessarily match those of legacy solutions. Additional hydraulic analysis of the existing piping system may be required when switching to listed antifreeze solutions. There are situations where existing factory premixed solutions of 30 percent propylene glycol by volume or 38 percent glycerin by volume are allowed to remain; these figures are based on a 2020 UL report that detailed the ability of low concentrations of propylene glycol and glycerin to resist ignition and substantial contribution to a fire.

Addition of nitrogen generation ITM requirements to align with NFPA 13

NFPA 25 requirements occasionally need to be updated to address changes made to the various installation standards whose ITM requirements are governed by NFPA 25. In this case, the 2022 edition of NFPA 13, Standard for the Installation of Sprinkler Systems, recognized that a nitrogen supply of at least 98 percent concentration has been shown to effectively reduce corrosion inside of a system, and as a result NFPA 13 now allows for the use of an increased C factor in dry and preaction sprinkler systems during the design phase. A C factor is used to indicate the smoothness of the interior surface of a pipe; the greater the C factor, the lower the friction loss will be as the water flows through the pipe, which allows for a greater carrying capacity.

Due to this change to NFPA 13, the committee determined that it was necessary to include ITM requirements to ensure those nitrogen supplies are adequate to maintain system design integrity. A system that was designed with a higher C factor due to the corrosion-reducing properties of nitrogen needs to maintain that nitrogen supply throughout the life of the system, or it risks developing corrosion that is not accounted for in the system design, which can reduce the effectiveness of the system.

Update to qualified personnel response time for remotely monitored automatic pump tests

A final proposed change important to note involves the time in which qualified personnel must respond to an abnormal pump condition during a remotely monitored automatic test.

In past editions of NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, five minutes was given as the time for personnel to respond in the event of pump activation. This time frame was carried over into NFPA 25 when remotely monitored automatic testing was added to the standard.

For the 2023 edition of NFPA 25, the committee recognized that the five-minute time frame was impractical given that the person observing the test was generally not on-site during a remote test. At the first draft stage, eight hours was proposed as the new time frame, but this was revised to four hours at the second draft stage; the technical committee felt that the four-hour response window ensures that fire protection systems are not impaired for an unnecessarily long period because a fire pump is generally necessary, where installed, for building fire protection systems to function properly. When the pump is out of service, a building is at a higher risk in case of a fire emergency. The technical committee felt the new response time frame should be adequate to address this issue.

These are just a few of the proposed changes for the next edition of NFPA 25. Like the maintenance of my new house, it’s clear that the maintenance and upkeep of fire protection systems is vital to ensuring that they function properly over their lifetimes and during emergencies. It is also important to update ITM requirements to make sure that the most up-to-date procedures and data are being implemented in the field. These key changes proposed for the 2023 edition of NFPA 25 go a long way toward ensuring that existing water-based fire protection systems are able to do their job over their service lifetime.

TOM HARRIS is a fire protection engineer in the electrical and fire protection systems division at NFPA. All photographs: GETTY IMAGES