Fire sprinkler systems are installed in buildings with the hope that they’ll never need to be used. But one can never know when a fire might start, so it’s vital to the safety of building tenants and property to ensure a sprinkler system is in good operating order. Here are five factors building managers can keep in mind to maintain a safe and functional fire sprinkler system with maximum efficiency.
1. Test Your System Remotely
NFPA 13 and NFPA 25 both require sprinkler water flow alarm device testing. An inspector operates a handle on a test valve to simulate the activation of the sprinkler system. For multi-story buildings and facilities with multiple buildings, this testing is time-consuming, as the inspector must visit each floor in person to test the valve. Frequently, as well, these valves are located behind locked doors or in hard-to-access places, adding complication to the job.
To improve efficiency, AGF Manufacturing, Inc. introduced RemoteTEST, which adds a solenoid to one of their famous TESTanDRAIN valves that can be activated by a local key switch, auxiliary panel, addressable FAC panel, or even a LAN system, while retaining the ability to be tested manually if needed. A remote testing option means there could be a panel in each building from which an inspector could test the system on every floor, or in complex facilities one hub on campus from which every system on the campus can be tested remotely. This increases efficiency and lowers the cost of testing, encouraging optimal system maintenance and readiness.
2. Prevent Corrosion
Corrosion, a major threat to sprinkler systems, occurs when a ferrous metal or alloy reacts with water and oxygen. It’s irreversible and can cause the accelerated deterioration of the system. Over time, corrosion can obstruct the flow of water through the sprinkler heads, making the system ineffective, increasing risk of injuries in a fire, and increasing property damage in a fire.
Most of the oxygen that contributes to corrosion in a wet system is from trapped air. Studies conducted by the National Fire Protection Association (NFPA) lead them to realize venting trapped air could help prevent corrosion and require air vents on wet sprinkler systems in the 2016 version of NFPA 13. The addition of an automatic air vent like AGF’s PURGEnVENT 7900AAV easily releases trapped air from the system, reducing the risk of corrosion.
3. Monitor Corrosion
If the maintenance team catches corrosion early, they still have time to handle it, or at least get a better idea of the rate of corrosion in the system. NFPA recognizes the importance of monitoring corrosion, as well. In NFPA 13 – Chapter 23, they say that a water supply with conditions contributing to microbiologically influenced corrosion (MIC – another source of corrosion), the system shall use one of several methods to handle it, and one of those methods is installing a corrosion monitoring station and monitoring it at established intervals.
AGF Manufacturing created a simple corrosion monitor, CORRinSITE, that requires no power to monitor corrosion on either wet or dry fire sprinkler systems. A plug made from the same material as the piping in the system is attached through a section of inline pipe or a mechanical tee. The plug has a chamber with a wear dimension of 0.040 inches (1/3 of the thickness of Schedule 10 pipe and 1/5 the thickness of Schedule 40 piping). When this corrodes through, moisture enters the chamber and turns a dot on its face from white to fluorescent orange. So, if CORRinSITE is installed in a new dry system with Schedule 10 pipe and the indicator turns orange in five years, the facility team can know that 1/3 of the pipe has corroded and can expect to replace the system in ten more years.
4. Protect Against Freezing
Dry sprinkler systems, although they are not full of water, still collect condensation. NFPA 13 requires auxiliary drains, which collect moisture and allow the draining of the moisture from the system without tripping the system and flooding it with water.
When temperatures drop below freezing, however, if the water remains in the drain, it can freeze inside of the barrel. If temperatures allow some of that ice to thaw and refreeze, an ice plug forms that prevents the freezing water from moving up the barrel and forces it downward, breaking the drain valve. When the ice thaws again, pressure is lost and the system is tripped. This requires an increase in labor cost to fix the broken valve, drain the system, and come back to continually drain any residual moisture from the tripped system to prevent the issue from repeating.
To protect against freezing auxiliary drains, AGF Manufacturing offers water detectors for their COLLECTanDRAIN auxiliary drain series. The detector creates visual and auditory alerts when the drain needs to be emptied. There’s even signage adhered to the drain that meets code and explains operation for less experienced personnel. For more problematic auxiliary drains, AGF offers a heated cabinet that prevents the water from freezing and has an alert when it’s in need of draining.
5. Protect Against Vandalism
Due to the nature of where dry fire sprinkler systems are necessary—often in parking structures or garden centers—the public often has access to auxiliary drains. With public access and convenient drain handles comes vulnerability to vandalism, whether accidental or malicious.
Anti-trip plates prevent the misuse of an auxiliary drain. AGF Manufacturing, for example, manufactures an anti-trip plate on their auxiliary drain (Model 5100 and 5200) that makes it physically impossible to improperly operate the valve. For added security, building managers can also order a locking kit that completely prevents the opening of the valves without a key.
It’s vital to keep a building’s fire sprinkler system in top shape should a fire start, but some issues like inefficient testing, corrosion, freezing, and vandalism, might not be top of mind for a building maintenance team. With these issues better in mind, and with innovative, efficient, code-compatible products from AGF Manufacturing, maintaining a building’s fire sprinkler system becomes much easier, leading to safer residents and property.
As seen in the September 2019 issue of Building Services Management magazine.