Understanding Pressure Measurements
Pressure is force applied per unit area and is measured in various units depending on the application. The SI unit is the Pascal (Pa), but common alternatives include bar, PSI (pounds per square inch), atmospheres (atm), and millimeters of mercury (mmHg). Each unit is prevalent in different industries and regions.
Tire pressure is typically measured in PSI in the US and bar in Europe. Blood pressure is measured in mmHg worldwide. Industrial and scientific applications often use Pascal or kilopascal. Weather reports may use hectopascals (hPa) or millibars, which are numerically equal.
Frequently Asked Questions
How do I convert PSI to bar?
Divide PSI by 14.5038 to get bar, or multiply bar by 14.5038 to get PSI. For example, 30 PSI equals approximately 2.07 bar. This conversion is commonly needed when checking tire pressure, as European specifications use bar while American specifications use PSI.
What is standard atmospheric pressure?
Standard atmospheric pressure is defined as 101,325 Pascals, which equals 1 atm, 1.01325 bar, 14.696 PSI, or 760 mmHg. This is the average air pressure at sea level and serves as a reference point for many scientific and engineering calculations.