What NFPA 25 Says About Fire Sprinkler Sign Requirements

NFPA 25, Standard for the Inspection Testing and Maintenance of Water-Based Fire Protection Systems, provides the minimum requirements for properly maintaining water-based fire sprinkler systems. Within this standard are several requirements for maintaining proper signage. Many in the industry are unaware of the requirements for proper signage. Of course, the requirements do change from edition to edition. In this blog we will cover the requirements for these signs.

Let us start with what is not required. Many technicians cite the building owner for not having signs such as main drain, inspector’s test connection, and alarm line signage. These signs are required at installation in accordance with NFPA 13, but they are not required to be maintained by NFPA 25.

Now for the signs that are required:

13.3 Control Valve

Section 13.3.1 states that each control valve shall have a sign and that the sign must indicate the area of the building that the control valve serves.

Section requires additional signs when more than one control valve must be closed to work on a system. It requires a sign on each valve referring to the existence of the other valves. For example, a looped system in a high-rise. If in stair A, there must be a sign in stair A referring to the control valve in stair B to isolate the system properly.

The sign does not appear to have a specific inspection frequency however, control valves are required to be inspected either weekly, monthly, or quarterly depending on how they are supervised. This would be the time to inspect for the proper signage.

The rest of the sign requirements are essentially found in Chapter 5.

5.2.5 Hydraulic Design information Sign

This section requires the sign to be inspected annually for legibility and that it is securely attached. The next section adds language for systems that are pipe schedule systems.

5.2.7 Information Sign

This sign is also required to be inspected annually but sends the inspector to Section 4.1.9 in the owner’s section for the requirements of this sign.

This section requires a sign to be placed at the control riser that supplies an auxiliary system to include antifreeze, dry, or preaction systems. This sign placed at the main control valve will indicate that there is another system somewhere else in the building.

The sign also must indicate the location of the area protected by the system, location of auxiliary drains, location of antifreeze systems, and location of heat tape.

5.2.8 General Information Sign

This sign has been required by NFPA 13 since the 2007 edition but was not required by NFPA 25 until the 2014 edition. This sign has many requirements and may cause some discussion between the building owner and service provider. Annex note A.5.2.8 states that this sign should satisfy the requirements for the information sign noted in Sections 5.2.7 and 4.1.9. Below is an example of the general information sign required by NFPA 13 and NFPA 25.

fire sprinkler sign - general information

5.2.9 Antifreeze Sign

This section was added in the 2017 edition of NFPA 25.  Prior to this sign requirement there was no specific requirements for an antifreeze sign.  This sign also sends the technichan to the owner’s section.  Section 4.1.10 requires the antifreeze signs contain the manufacture of the antifreeze, the volume of the system, type or brand of antifreeze, and percentage of the antifreeze solution.

fire sprinkler sign for antifreeze

All the signs discussed are required by NFPA 25 and should be cited as a deficiency if not present where required. The signs that are required by NFPA 13, such as the main drain sign, are good ideas to have but are not required by NFPA 25.  If a technician wants to suggest having these signs, it should be done on an observation report. Remember that if you can’t cite it don’t write it.


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