#PSI DEFINITION FULL#

The conversions to and from SI are computed from exact definitions but result in a repeating decimal. Ultimate strength of ASTM A36 steel: 58,000 psi.Land Rover Td5 diesel engine fuel injection pressure: 22,500 psi.Airbus A380 hydraulic system: 5000 psig.

#PSI DEFINITION FULL#

Full SCBA (self-contained breathing apparatus) for interior firefighting operations: 4500 psig.Full SCUBA (self-contained underwater breathing apparatus) tank overpressure (common): 3000 psig.Full SCBA (self-contained breathing apparatus) for IDLH (non-fire) atmospheres: 2216 psig.Union Pacific Big Boy steam locomotive boiler: 300 psig.Steam locomotive fire tube boiler (UK, 20th century): 150–280 psig.Road racing bicycle tire overpressure: 120 psig.Air brake (rail) or air brake (road vehicle) reservoir overpressure (common): 90–120 psig.Bicycle tire overpressure (common): 65 psig.Automobile tire overpressure (common): 32 psig.Atmospheric pressure at sea level (standard): 14.7 psia.Boost pressure provided by an automotive turbocharger (common): 6–15 psig.Natural gas residential piped in for consumer appliance 4–6 psig.Blood pressure – clinically normal human blood pressure (120/80 mmHg): 2.32 psig/1.55 psig.

Main article: Orders of magnitude (pressure) When gauge pressure is referenced to something other than ambient atmospheric pressure, then the units would be pounds per square inch differential ( psid). For example, a bicycle tire pumped up to 65 psig in a local atmospheric pressure at sea level (14.7 psi) will have a pressure of 79.7 psia (14.7 psi + 65 psi). The converse is pounds per square inch gauge ( psig), indicating that the pressure is relative to atmospheric pressure. Since atmospheric pressure at sea level is around 14.7 psi (101 kilopascals), this will be added to any pressure reading made in air at sea level. Pounds per square inch absolute ( psia) is used to make it clear that the pressure is relative to a vacuum rather than the ambient atmospheric pressure. In SI units, 1 psi is approximately equal to 6895 Pa. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. The pound per square inch or, more accurately, pound-force per square inch (symbol: lbf/in 2 abbreviation: psi) is a unit of pressure or of stress based on avoirdupois units. A pressure gauge reading in psi (red scale) and kPa (black scale)

Psi definition