Which of the following is a listed relief valve setting for a propane tank?

• A. 250 psig
• B. 300 psig
• C. 325 psig
• D. 350 psig

Answer: (C)

Relief devices on propane tanks are there to prevent overpressure when temperatures rise or other conditions cause pressure to build. A listed relief valve has a fixed set pressure printed on it and is designed specifically for propane service. That set pressure is chosen to protect the tank without causing venting during normal heating. For standard propane tanks, the listed relief valve setting is typically 325 psig, which provides a safe margin above normal service pressures but well below the tank’s maximum design pressure. Values much lower would vent too often, while higher values could allow dangerous pressure to develop. So 325 psig is the correct listed setting.