psi, bar, pascal, atm.
Converts between bar, PSI, atm, Pa, and mmHg. Common: 1 bar ≈ 14.504 PSI; 1 atm = 1.01325 bar ≈ 14.696 PSI.
PSI is common in US tire and hydraulic pressures; bar and atm in industrial contexts.
Weather reports add another common unit to this mix — barometric pressure is often given in inches of mercury (inHg) in the US or hectopascals (hPa) elsewhere, both of which relate back to the same underlying pressure scale.
1 bar ≈ 14.50 PSI.
Both. US owners' manuals typically show PSI; European show bar. 32 PSI ≈ 2.2 bar.
Standard atmospheric pressure at sea level: 101,325 Pa, 1.01325 bar, or 14.696 PSI.
Different fields standardized independently — meteorology, engineering, and automotive industries each settled on the unit most convenient for their instruments long before there was pressure to unify them.