Fire Protection Valves – A Critical Component of Life Safety Systems

Aug 14, 2023 | Company News, News

Fire protection systems are a critical component of life safety in commercial and residential buildings. Their purpose is to detect fires early, contain fires and smoke, and extinguish fires rapidly to minimize damage and loss of life. A key element of many fire protection systems are the specialized valves used to control water flow and isolate different zones of the system. Three major types of valves used are fire protection gate valves, check valves, and strainer valves.

Fire Protection Check Valves

Fire Protection Gate Valves

Gate valves are used to start and stop the flow of water in fire protection systems. They work by opening or closing the valve’s “gate” which is a disk or plate inside the valve body. When open, the gate is fully retracted into the valve body allowing full water flow. When closed, the gate extends across the entire diameter of the pipe stopping flow. Gate valves are operated manually by handwheel or automatically by an actuator and control system.

There are two main types of gate valves used in fire protection – outside screw and yoke (OS&Y) and butterfly valves. OS&Y gate valves are the most common. They provide a tight seal when closed and have a rising stem that visually indicates if the valve is open or closed. Butterfly valves are lighter weight but typically do not seal as tightly as OS&Y valves.

Fire protection gate valves need to be specifically designed for fire protection service. They require features like the ability to operate when exposed to high water pressure, the ability to operate after long periods of inactivity, and construction that meets fire endurance ratings. Using general purpose gate valves in a fire protection system could render the system inoperable when needed in an emergency.

Fire Protection Check Valves

Check valves allow water to flow in only one direction in a piping system. They are commonly used in fire protection between the water supply and the system to prevent backflow of water. This backflow could occur due to pressure fluctuations or breaks in the system piping. Check valves are weighted or spring loaded to allow flow in the normal forward direction while closing tightly to prevent any reverse flow.

There are many check valve designs including swing check, wafer check, dual plate check, and others. Swing checks are likely the most widely used in fire protection. They consist of a hinged disk that swings open with forward flow and then springs closed when flow stops or reverses. Checks need to be installed in the proper direction and the piping system needs to maintain enough velocity during water flow events to keep the check valve open.

As with gate valves, check valves designed specifically for fire protection service are required. They feature robust designs capable of handling the sudden opening and high flow rates that can occur in a fire event. Their seat designs ensure tight closure to prevent unwanted backflow in an emergency.

Fire Protection Strainer Valves

Strainer valves contain screens to filter out dirt, scale, debris and other solids that could be present in water flowing through the fire protection system. They protect other components from damage and blockage that could hamper performance. Strainers are available in wye pattern, basket pattern, and other styles with different screen mesh openings.

Strainers need regular maintenance because as they collect debris over time, the flow through the strainer gradually decreases requiring its cleaning or replacement. Therefore, strainer valves need to be installed in accessible locations and sized properly for the service. Occasional flushing is also required to keep strainers functioning optimally.

Any valving on a fire protection system needs careful commissioning to ensure it is functioning per specifications. Periodic testing and inspection of all valves is also required. Gate valves, check valves and strainers on sprinkler, standpipe, or other fire suppression systems need to operate reliably in an emergency to protect lives and property. Selecting and maintaining the right fire protection valves for the application is a key fire safety responsibility.