If receiving 16-90 psig from an outside source, for what pressure should the system be designed?

Designing a system to accommodate incoming pressures is crucial for ensuring safe and efficient operation. When determining the appropriate design pressure for a system receiving a range of 16 to 90 psig from an outside source, it's vital to consider a safety margin that accounts for fluctuations in the incoming pressure as well as potential equipment failure.

The recommended practice is to select a design pressure that provides sufficient headroom above the maximum expected pressure. The industry standard suggests adding a safety margin of 25% to 50% to the maximum expected operating pressure. In this scenario, the maximum pressure from the outside source is 90 psig. By applying a 25% increase to 90 psig, the design pressure would effectively be 112.5 psig. This value suggests that a design pressure of 125 psig is a suitable choice because it falls within the recommended range while still providing a safety buffer.

Choosing this pressure helps ensure that the system can handle any operational spikes or variations safely while meeting regulatory and operational requirements.