Massachusetts Plumbers Journeyman Practice Exam

In buildings that are occupied other than residential dwellings, what must the water supply line to each fixture or piece of equipment be provided with?

1. Check valve

2. Pressure relief valve

3. Valve or fixture stop

4. Pressure reducing valve

The correct answer is: Valve or fixture stop

In buildings occupied for purposes other than residential dwellings, providing a valve or fixture stop on the water supply line to each fixture or piece of equipment ensures that individual control over the water supply is accessible. This is crucial for maintenance and emergency situations, allowing for specific fixtures or equipment to be shut off without disrupting the entire water supply to the building. This facilitates quick repairs and minimizes water damage in case of leaks or failures. The other options, while important in certain contexts, do not specifically relate to the requirement for individual control at fixtures. Check valves prevent backflow, pressure relief valves protect against overpressure in systems, and pressure reducing valves are installed to manage supply pressure. However, none of these fulfill the specific need for localized control and isolation that the valve or fixture stop provides.