What pressure must an overpressure protection device guard against when gas supply is delivered at 2 psi?

An overpressure protection device is designed to prevent excessive pressure from causing damage to the gas system and ensure that the downstream equipment operates safely within its specified limits. When gas is supplied at 2 psi, the corresponding pressure measurement in inches of water column (w.c.) is an important factor in determining the safe operational parameters of the system.

In the conversion from psi to inches of water column, it is essential to recognize that 1 psi is equivalent to approximately 28 inches w.c. Therefore, 2 psi converts to about 56 inches w.c. However, the overpressure protection device must be set to guard against any unexpected pressure increases that may occur in the system.

Typically, regulatory standards dictate that the protection device should activate well below the maximum operating pressure to avert any risk of component failure or system hazards. This means that the overpressure protection device should protect against pressures significantly lower than the total allowable pressure, usually around 10% of the maximum pressure.

In this context, a safe threshold for an overpressure protection device guarding against 2 psi would typically fall under the range of 14 inches w.c. or less. This threshold ensures a significant safety margin, allowing the device to manage any pressure fluctuations while keeping the system safe.