Red Seal Gasfitter — Class B Practice Exam

What is a two-stage regulator used for?

1. To provide precise pressure control for appliances requiring stable pressure

2. To increase overall gas flow rates

3. To act as a safety shut-off device

4. To regulate temperature in gas appliances

The correct answer is: To provide precise pressure control for appliances requiring stable pressure

A two-stage regulator is specifically designed to provide precise pressure control for gas appliances that require a stable pressure supply. This type of regulator functions in two steps: the first stage reduces the high inlet pressure from the gas source to an intermediate pressure, and the second stage further reduces this intermediate pressure to a level suitable for safe operation of the appliance. This staged approach allows for more accurate pressure regulation, effectively accommodating fluctuations in upstream gas supply while ensuring that appliances receive a consistent and stable gas pressure. This stability is crucial for the efficient and safe operation of appliances, particularly those that are sensitive to pressure variations. Other functions, such as increasing overall gas flow rates, safety shut-off mechanisms, or temperature regulation, do not align with the primary purpose of a two-stage regulator. While such functionalities are important in the context of gas systems, they are handled by different types of devices. The focus of a two-stage regulator is on maintaining an accurate and reliable pressure output, which is essential for the proper functioning of various gas appliances.