Multiply atmospheres by 14.6959
1 atm equals 101,325 pascals, the defined standard atmospheric pressure at sea level (15°C, dry air). 1 PSI equals 6,894.76 pascals. Dividing gives 14.6959 PSI per atm, usually written as 14.696 or 14.7. The conversion is exact at the definition level — atmospheric pressure in reality varies with weather and altitude, but the unit 'atm' is fixed by SI definition and does not change with conditions.
The atmosphere (atm) is a pressure unit historically defined as the average air pressure at sea level. Standardized at exactly 101,325 pascals, it remains useful in chemistry, scuba diving, and meteorology. PSI (pounds per square inch) is the everyday US pressure unit.
One atmosphere equals 14.696 PSI. The conversion comes up when reading chemistry papers that quote reaction pressures in atm, planning scuba dives where ambient pressure increases by one atm per ten meters of depth, or interpreting weather data where storm pressures vary fractions of an atmosphere.
Outside specialized fields, bar and PSI have largely replaced atm in industrial measurements.
Ambient pressure increases 1 atm every 10 meters of saltwater depth. Tank pressures listed in PSI need atm conversion when calculating gas consumption against depth-pressure schedules.
Papers and SDS sheets quote reaction or storage pressure in atm. Lab gauges and regulators read PSI. Convert to set up procedures accurately.
Pressure altimeters reference one standard atm. Pilot training tables mix units between atm, mb (millibars), and PSI when discussing service ceilings or cabin pressurization.
Soda saturation is specified in volumes-of-CO2 or atm of partial pressure. Force-carbonation home kegs and commercial systems calibrate in PSI.
Track-day setup guides for European cars sometimes list cold pressure in atm. Air gauges and compressors at most tracks read PSI.
Multiply atm by 14.696. So 1 atm = 14.7 PSI, 2 atm = 29.4 PSI, 5 atm = 73.5 PSI, 10 atm = 147.0 PSI.
1 atmosphere equals 14.696 PSI, typically rounded to 14.7 PSI for non-engineering use.
Almost, but not exactly. 1 atm = 101,325 Pa = 1.01325 bar. The 1.3% difference matters in precise scientific work but is negligible for tire pressure and similar everyday uses.
At sea level the column of air above one square inch of surface weighs approximately 14.7 pounds. The unit 'atm' codifies this average so calculations don't depend on local weather.
About 10 meters (33 feet) of saltwater. Each 10 meters of depth adds one atmosphere of pressure on top of the one atm already at the surface. At 20 meters total ambient pressure is 3 atm.
No. The unit 'atm' is fixed by definition — exactly 101,325 Pa. Actual ambient air pressure at altitude is lower, but that is measured in pascals or millibars, not in atm.
Gauge pressure is measured relative to ambient atmospheric pressure (so at sea level, gauge atm = absolute atm − 1). Most lab gauges read gauge. The atm unit itself is absolute by convention.
Rarely. Modern engineering favors bar, kPa, or PSI. Atm survives mainly in chemistry, diving, meteorology, and legacy documents. SI deprecates it but does not forbid it.