What device must be installed where the gas pressure is higher than the design pressure of the equipment or supply lines?

What device must be installed where the gas pressure is higher than the design pressure of the equipment or supply lines?

• A. A check valve
• B. An inline filter
• C. A regulator
• D. A relief valve

Answer: (C)

When there is more gas pressure upstream than the equipment or supply lines are designed to handle, a regulator is needed. A regulator lowers the high upstream pressure to a stable, lower downstream pressure and holds that set point even as the supply pressure varies. This protects appliances and piping from overpressure and ensures safe, consistent operation of the gas system. The other devices don’t serve this role: a check valve prevents backflow but doesn’t reduce pressure; an inline filter cleans gas but doesn’t regulate pressure; a relief valve vents excess pressure to prevent damage, but it’s for overpressure protection rather than continuous down-regulation in normal operation.

When there is more gas pressure upstream than the equipment or supply lines are designed to handle, a regulator is needed. A regulator lowers the high upstream pressure to a stable, lower downstream pressure and holds that set point even as the supply pressure varies. This protects appliances and piping from overpressure and ensures safe, consistent operation of the gas system.

The other devices don’t serve this role: a check valve prevents backflow but doesn’t reduce pressure; an inline filter cleans gas but doesn’t regulate pressure; a relief valve vents excess pressure to prevent damage, but it’s for overpressure protection rather than continuous down-regulation in normal operation.