Massachusetts Plumbers Journeyman Practice Exam

What should be the size of the relief vent concerning the vent stack it connects to?

1. Equal to the size of the vent stack

2. Twice the size of the vent stack

3. Half the size of the vent stack

4. One size smaller than the vent stack

The correct answer is: Equal to the size of the vent stack

The correct response indicates that the size of the relief vent should be equal to the size of the vent stack it connects to. This is important because maintaining the same size for both the relief vent and the vent stack ensures that the system can effectively handle pressure and allow for proper air circulation. This alignment helps prevent issues such as back pressure, siphoning, or inadequate ventilation, which can lead to drainage problems or trap failures. In plumbing systems, ensuring that vents are appropriately sized is crucial for maintaining the overall health and efficiency of the system. Proper venting allows wastewater to flow freely while providing air in the drainage system to prevent vacuum conditions. Therefore, matching the sizes of the relief vent and the vent stack is critical in achieving optimal system performance.