Today’s infrastructure is bustling with components so unassuming, that nobody gives them a second glance (or thought) when they pass them by. Yet, some of these implements became so critical for our overall safety – that they became irreplaceable.

One of these components is a humble Post-Indicator valve (PIV). But, make no mistake – PIV is humble only in appearance and not in the least in purpose. Let’s explore what PIVs are, their way of work, and the different types in use today.

What is a PIV and how does it work?

A Post-Indicator Valve is a type of valve commonly used in modern-day fire protection and water supply systems. Also known as a Post-Indicator Hydrant (PIH) or Indicator Post Valve, its primary function is to control the flow of water from an underground water main to a fire hydrant, sprinkler system, or other fire suppression devices. Their intuitive and user-friendly design makes them remarkably simple to operate, which is why PIVs have become an essential part of modern infrastructure.

How does a PIV work?

The PIV typically consists of an underground valve (conventional gate, ball, or butterfly valve) connected to the water main. The valve is operated by a rising stem, which extends from the underground valve to the indicator post above ground.

The indicator post is installed in a visible and accessible location, and is usually colored to make finding it easy in any weather condition or emergency. On top of the post, there’s a tamper-proof, lockable actuator (operating nut) that serves to open/close the valve. Here, we can also find an indicator that shows in which state the valve currently is (i.e. “OPEN” or “SHUT”).

To operate the valve, firefighting or maintenance personnel will use a universal PIV key or wrench to turn the operating nut at the top of the indicator post, which in turn rotates the underground valve, controlling water flow to the fire hydrant. The entire process takes a few minutes only (e.g. 1-2), making PIVs critical for facilitating firefighting and maintenance efforts.

What are the different types of post-indicator valves?

Typically, PIVs are roughly separated into three categories, based on their installation method and location:

• Ground posts: Features buried base and are used when the main valve is located outside the building;
• Wall posts: These units are mounted on the building wall, primarily in places where the water main passes through the wall cavity.
• Pedestal posts: Similar to ground posts, but with the base bolted to the ground instead of being buried. These are used when the valve is inside the building.

However, although they operate on the same principle and serve the same purpose, there are variations in design, materials, and features adapted to the specific applications or environmental conditions. For example:

• Gate valve type PIV: Uses a gate valve as the underground valve, suitable for most water supply systems.
• Ball valve type PIV: Employs a ball valve for quicker operation and tighter shut-off, often used in high-pressure systems.
• Post indicator hydrant (PIH) with built-in valve: A self-contained unit where the PIV is integrated into the fire hydrant, saving space and facilitating installation.
• Lockable PIV: Includes a locking mechanism to prevent unauthorized operation, enhancing security and tamper resistance, a common feature in the majority of today’s PIV models.
• Supervisory signal PIV: Designed to send a signal to a monitoring system or fire alarm panel when the valve is operated, ensuring real-time status updates.
• Freeze-resistant PIV: Constructed with materials and designs that prevent freezing in cold climates, ensuring the valve remains operational in harsh winter conditions.
• Traffic durable PIV: Built with heavy-duty materials and a significantly more robust design to withstand the challenges of high-traffic areas.

Where can I find a top-quality post-indicator valve for sale near me?

Blair Supply is your premier destination for any and all high-grade water main and wastewater materials, boasting nearly 70 years of industry presence and a track record of excellence. We collaborate with some of the USA’s leading manufacturers to bring you solutions that are durable and reliable, facilitating your efforts and your success. 

Whether your project is taking place in Downtown Rochester, elsewhere in the State of New York, or anywhere else in the US, you can count on us to deliver on the promise of quality in a timely, dependable manner. Reach out to us today!