The main water shutoff valve in a house or building shall be _____ _____

The main water shutoff valve in a house or building shall be _____ _____

• A. Full Port
• B. Ball Valve
• C. Globe Valve
• D. Gate Valve

Answer: (A)

When choosing a main water shutoff, the valve should be full port (full bore). This means the interior passage matches the pipe diameter, so when the valve is fully open there’s no restriction to flow. That unrestricted passage minimizes pressure drop and turbulence, making it easier to supply the entire system, flush lines, or work with the water meter during maintenance. In other valve designs, the passage can be narrower than the pipe, creating a bottleneck that reduces flow and can complicate service or meter work. So the defining feature for a main shutoff is a full-port design, ensuring the valve behaves like a straight piece of pipe when open.

When choosing a main water shutoff, the valve should be full port (full bore). This means the interior passage matches the pipe diameter, so when the valve is fully open there’s no restriction to flow. That unrestricted passage minimizes pressure drop and turbulence, making it easier to supply the entire system, flush lines, or work with the water meter during maintenance. In other valve designs, the passage can be narrower than the pipe, creating a bottleneck that reduces flow and can complicate service or meter work. So the defining feature for a main shutoff is a full-port design, ensuring the valve behaves like a straight piece of pipe when open.