psia
Units & Measurements abbreviation · Engineering Unit
| Stands for | Pounds per square inch absolute |
|---|---|
| Categories | Units & Measurements |
psia stands for Pounds per square inch absolute, an engineering unit abbreviation.
Pressure measured relative to a perfect vacuum, so the atmosphere at sea level reads about 14.7 psia. Thermodynamics, aerospace, refrigeration tables and process engineering use absolute values for calculations.
Example: The vessel operates at 150 psia, about 135 psig at sea level.
Usage notes
Absolute pressure equals gauge pressure plus local atmospheric pressure: psia = psig + 14.7 at sea level. Gas laws and steam tables require absolute pressure, and plugging gauge values into them is a classic engineering error.
Related abbreviations
More engineering unit abbreviations
- NPT – National Pipe Thread
- Pa – Pascal
- ppb – Parts per billion
- ppm – Parts per million
- PS – Pferdestärke (metric horsepower)
- psi – Pounds per square inch
- psig – Pounds per square inch gauge
- R – Degree Rankine
- rad – Rad (radiation absorbed dose)
- rem – Roentgen equivalent man
- RPM – Revolutions per minute
- SEER – Seasonal Energy Efficiency Ratio