Massachusetts 2nd Class Fireman's Practice Exam

Which component is designed to prevent backflow in a steam system?

1. Check valve

2. Relief valve

3. Globe valve

4. Ball valve

The correct answer is: Check valve

The check valve is specifically designed to prevent backflow in a steam system. It allows fluid to flow in only one direction and automatically closes if the flow reverses, thereby protecting system integrity and preventing any potential damage that could occur from reverse flow. In a steam system, maintaining the correct flow direction is critical for safety and efficiency. The check valve acts as a safeguard to ensure that steam travels from the boiler to the distribution system without allowing any of it to flow back into the boiler, which could lead to overheating or other operational issues. Other types of valves, such as relief valves, are designed for pressure regulation and safety by releasing excess pressure, but they do not prevent backflow. Globe and ball valves are primarily used to control flow rather than to prevent backflow, making them unsuitable for this specific function.