Massachusetts Plumbers Journeyman Practice Exam

What pressure should be maintained in a waste and vent system during testing?

1. 2 P.S.I.G.

2. 5 P.S.I.G.

3. 8 P.S.I.G.

4. 10 P.S.I.G.

The correct answer is: 5 P.S.I.G.

The correct pressure to be maintained during testing of a waste and vent system is indeed 5 P.S.I.G. This pressure is established to ensure that the system is adequately tested for leaks and structural integrity. Maintaining this pressure allows for a thorough examination of joints, fittings, and connections in the waste and vent system, which is crucial for preventing future leaks that could lead to significant sanitary and structural issues. The 5 P.S.I.G. standard is backed by plumbing codes and best practices which underline the importance of ensuring that the system can hold pressure without any loss, indicating that it is safe and reliable for operational use. Testing at this specific pressure helps to reflect real-world conditions that the system will encounter, thereby ensuring that it meets safety and efficiency standards. Choosing a lower or higher pressure may not provide an accurate assessment of the system's integrity. A lower pressure might miss minor leaks, while a higher pressure could cause undue stress on certain components that may not be designed to handle those levels, potentially leading to failure.