Gasketed Joint in underground piping is a sealed joint for what purpose?

• A. A loose joint for easy replacement.
• B. A joint that reduces water pressure.
• C. Sealed joint for air service in underground pipes.
• D. A joint used only above ground.

Answer: (C)

A gasketed joint in underground piping is meant to create a tight, watertight seal that also allows an air service connection to be used for testing and purging the line. When installing underground sprinkler piping, lines are often pressurized with air to verify joints and purge debris before filling with water. The gasketed joint keeps that air from leaking out and prevents groundwater or soil from entering, which is essential for a reliable test and long-term performance. It’s not about making a loose joint for replacement, it doesn’t purposefully reduce water pressure, and it isn’t limited to above-ground use—the sealed, air-service-capable nature is specifically for underground installations.