What does PSIA stand for?

PSIA stands for "Pressure measured with atmospheric pressure included." This term indicates that the measurement of pressure is taken in relation to the surrounding atmospheric pressure. In many applications, particularly in engineering, it's crucial to understand whether the pressure readings account for atmospheric conditions, as this impacts the calculations and interpretations related to gas behaviors, fluid dynamics, and various systems operating under different pressure conditions.

Understanding PSIA helps engineers and technicians apply the correct formulas and calculations when designing and maintaining systems that involve gases or liquids under pressure. For example, if someone is measuring the pressure inside a tank, knowing whether that measurement is relative to atmospheric pressure (PSIA) or to a vacuum (PSIG - pounds per square inch gauge) is essential for ensuring accurate system operation and safety.