Which component is used to contain pressurized water during a wet tap?

• A. Flapper valve
• B. Check valve
• C. Ball valve
• D. Gate valve

Answer: (A)

During a wet tap you need a temporary, reliable seal that can hold back live pressure while penetrating the main and installing the branch. A flapper valve provides that, using a flexible rubber flap seated against a valve seat to create a tight seal against the pressurized water. This lets the tapping tool be driven into the pipe without a geyser of water, and once the branch is secured, the valve can open to restore normal flow. Ball, gate, and check valves are great for controlling or preventing backflow in a pipe, but they aren’t designed to serve as the rapid, dependable pressure containment needed specifically during the wet-tap operation. That targeted containment role is why the flapper valve is the best choice.