Red Seal Gasfitter — Class A Practice Exam

What is the purpose of a gas shut-off valve?

1. To regulate gas pressure during appliance operation

2. To stop the flow of gas in the event of an emergency or for maintenance

3. To enhance gas flow efficiency

4. To monitor gas consumption

The correct answer is: To stop the flow of gas in the event of an emergency or for maintenance

A gas shut-off valve serves a critical role in safety and maintenance by allowing the operator to stop the flow of gas quickly in an emergency situation or during maintenance activities. This feature is essential for preventing potential hazards, such as gas leaks or fires, by enabling prompt action to mitigate risks. In the event of a detected leak, malfunctioning appliance, or other emergency situations, the ability to immediately shut off gas flow can be lifesaving. Similarly, during maintenance or repair work on gas appliances, the valve ensures that no gas is being supplied, thus minimizing the risk of accidents while technicians are working. The other aspects of gas operation—like pressure regulation and flow efficiency—are important but are managed by different components within the gas system. Monitoring consumption falls under metering and is not the primary function of a shut-off valve. Thus, the main purpose of the gas shut-off valve is to provide a means to stop gas flow for safety and maintenance.