What is the pressure of the earth's atmosphere, measured in psia?

The pressure of the earth's atmosphere at sea level is approximately 14.7 pounds per square inch absolute (psia). This value represents the total atmospheric pressure when measuring absolute pressure, which includes atmospheric pressure above a complete vacuum. Understanding this value is important in various applications, including medical gas systems, where the pressure of gases needs to be precisely monitored and maintained.

In contexts like medical gas supply systems, knowing the standard atmospheric pressure is crucial when calculating how gases behave under different conditions and for ensuring that they are delivered at the correct pressures for safe and effective use. This standard pressure influences how systems are designed, tested, and operated according to regulations such as those outlined in NFPA 99.