Fire hydrants are critical components of any emergency response system. Since their creation, they have revolutionized and greatly improved the way we fight fires. Today's fire hydrants are mostly dry barrel style, meaning they have the ability to pump water out when needed and shut the water off when it's not needed — mostly to prevent the water from freezing in cold conditions.
While the overall design of a hydrant is relatively standard, there are still many moving parts for firefighters to pay attention to — especially fire hydrant valves. There are four primary types of fire hydrant valves, found at the bottom of the hydrants. They open and close the plug that lets water through. When open, a valve fills the hydrant with water while sealing drain holes so that the water is ready to use. When closed, the valve prevents water from entering the fire hydrant and drains excess water through drain holes.
What Are Critical Fire Hydrant Valves and Why Are They Important?
Fire hydrant valves connect hydrants to underground water mains, allowing high-pressure water to flow through them. Firefighters tap into this secondary water source to support fire engines or control serious blazes. To access these water sources, firefighters use a wrench that opens the stem nut at the top of the hydrant, which opens the valve and allows water to flow into the barrel.
Fire hydrant valves facilitate the connection to the underground water supply, providing firefighters with reliable volumes of water to combat fires. It's difficult to discern the amount of water needed to put out a fire, so firefighters need as much support as they can get. Valves offer a direct connection to the municipal water supply, ensuring the availability of water.
Types of Fire Hydrant Valves
Understanding valve functions and types is key to making good use of fire hydrants. So, what are the different types of valves, and what are they used for? Read on to learn more about each one and its benefits for firefighting missions.
What Is a Gate Valve?
The gate valve is the most common type of fire hydrant valve. They have a simple, cost-effective and reliable design. They are also easy to use, opening and closing with minimal resistance. More likely than not, your municipality has hydrant gate valves. These valves are made for controlling water flow without damaging the fire hydrant itself, which is why they're the most common firefighting hydrant valves.
Gate valves in fire hydrants are simply used to turn the water on and off. They often include a crank handle that makes it much easier for firefighters to quickly get water flowing in an emergency. These valves are most commonly made from cast iron and coated with a type of rubber to prevent wear and corrosion from the consistent water flow. Gate valves are also best for use in old hydrants or cold weather because they can throttle the water in a pipeline even when water is slow to flow or flows uncontrollably.
What Is a Butterfly Valve?
Another type of critical fire hydrant valve is the butterfly valve. These valves are best used for controlling the flow of water in hydrants. They are operated by a disc system that turns the valve 90 degrees to an open or closed position. However, a very small section of the butterfly valve is always open, whereas gate valves must be completely open or closed. The disk is operated by a handwheel that turns the valve to an open or closed position.
Butterfly hydrant valves can also be used in tandem with other equipment to create a position indicator for firefighters to see whether the valve is closed at a given time. Due to their ability to operate at lower torque than gate valves, butterfly valves are typically cheaper, lighter and easier to use than hydrant gate valves. This has positioned butterfly valves as an up-and-coming firefighting hydrant valve that many installers prefer.
Butterfly valves could replace gate valves as the most common critical fire hydrant valve in the future, so it's important for firefighters to monitor these valve types in hydrants.
What Is a Check Valve?
The next most popular type of fire hydrant valve is a check valve. These valves are specially designed to prevent hydrant water from backing up and otherwise affecting municipal water systems. Typically, the water used for firefighting comes from multiple sources, including municipal water. However, sometimes issues can occur — hydrant water can be mixed with drinkable water, contaminating it, or water from fire sprinklers might end up in street drains that lead to municipal water systems. This contamination of municipal water is known as backflow.
Check valves eliminate backflow by only opening in one direction when water flows out. They are great options for municipalities where contamination is an issue or where backflow needs to be prevented. Check valves are often used with hydrants that are connected to community water supply networks. Their primary advantage is the single-direction flow, which protects water system integrity by preventing contamination.
What Is a Plug Valve?
Plug valves are the least common type of critical fire hydrant valves. They are typically used more in wastewater applications rather than for firefighting. Due to the need for much greater force because of their high friction, it's much more difficult for materials to flow through plug valves. Therefore, these valves aren't recommended for typical firefighting water usage.
Plug valves are most commonly used in municipal waste management systems for controlling and distributing contaminated liquids or sludge. They can be used both above and below ground. There are four types of plug valves — lubricated, nonlubricated, expandable and eccentric. Each is used for different applications, depending on the materials used within the systems.
Similar to butterfly valves, plug valves can either completely isolate a liquid or allow for the flow of liquid. They effectively seal water passage, preventing leakage even under high pressure. These valves are also used in applications like oil and gas extraction or mining to prevent contaminants from affecting water sources. Because they handle different types of liquids, such as high-debris water and sludge, plug valves are made with strong metals able to handle abrasive particles.
Fire Hydrant Safety Measures
Fire hydrants are valuable devices that provide emergency responders with much-needed water to extinguish fires. However, these heavy metallic devices hold high-pressure water, so operating them can be a safety hazard without the proper precautions. Here are hydrant safety measures for firefighters:
- Position yourself behind fire hydrants when operating them.
- Ensure that no objects or bystanders are within 10 feet of a hydrant when operating it.
- Always wear appropriate personal protective equipment, such as helmets and gloves, to ensure maximum protection.
- Ensure that the flow of water is under control at all times.
- Open the hydrant valve gently to avoid injuries or damaging water infrastructure due to sudden pressure surge.
Compliance Tips for Fire Departments
In the United States, regulations regarding fire hydrants are determined by local governments and fire departments. Due to the unique circumstances surrounding hydrants, such as population and building types, the appropriate local authority must set requirements about spacing. The National Fire Protection Association (NFPA) provides standards regarding water pressure, flow rates, testing and maintenance.
When it comes to maintenance, it's recommended to partner with a specialist to ensure proper servicing for different fire hydrant types and components. Here's a checklist for valve and hydrant maintenance and inspection:
- Inspect for obstructions that may interfere with operations.
- Check that the caps are not cracked or missing.
- Inspect main valves, nozzles and gaskets for leaks and signs of damage.
- Flush the hydrant to eliminate foreign substances from the lead line.
- Lubricate the hydrant system to prevent corrosion.
Contact Bunker Gear Specialists to Order Your Critical Fire Hydrant Valves
Fire hydrants are an essential and critical piece of any emergency response system. It’s important for firefighters, municipal workers and others to be aware of the various types of fire hydrant valves and able to identify and operate them in emergencies. When the next emergency occurs, you won’t waste time trying to get water to flow because you don’t understand the system. Prepare ahead of time by knowing the different fire hydrant valve types and how they work.
Bunker Gear Specialists offers top-of-the-line equipment for all firefighting needs, from helmets to clamps. Our gate valve is ready to go and will handle your water sources with ease, even in the toughest situations. Contact us today for more information about our equipment, and learn how we can help you continue saving lives.
