Zero psia is approximately equal to what value at sea level?

Zero psia (pounds per square inch absolute) refers to a pressure measurement where the pressure is compared to a perfect vacuum. At sea level, the standard atmospheric pressure is approximately 14.7 psi. This means that 14.7 psi is the absolute pressure exerted by the atmosphere at sea level.

When we say the pressure is zero psia, it indicates that we are measuring pressure relative to a vacuum; hence, atmospheric pressure is typically considered as 14.7 psi at sea level. Therefore, when converted, zero psia equals the atmospheric pressure of 14.7 psi at sea level. Understanding that psia measures pressure relative to a complete vacuum helps clarify this relationship. The other options (0 psi, 29.9 psi, and 30.0 psi) do not correspond to the standard atmospheric pressure and therefore do not represent the correct relationship to zero psia at sea level.