Pressure Units

Many of our precision tube products must withstand huge amounts of pressure when they’re in use, so we’ve prepared this page detailing pressure for your reference.

Atmospheric pressure is the pressure at any point in Earth’s atmosphere. Most of the time, atmospheric pressure is closely approximated to the hydrostatic pressure caused by the weight of the air above the measurement point.

A column of air one square inch in cross section, measured from sea level to the outer edge of Earth’s atmosphere, would weigh approximately 14.7 pounds per foot. Comparatively, a column of air one square metre (11 sqft) column would weigh about 10.2 metric tonnes or 10,200kg. That’s equivalent to 100 kilonewtons, the SI unit used to measure pressure.

One Newton per square metre (N/m²) is also called a Pascal (Pa).

   1 MPa = 106 Pa = 106 N/m² = 1 N/mm²


  Pascal
(Pa)/ N/m²
Bar
(bar)
kg/cm²
Technical
atmosphere
(at)
Atmosphere
(atm)
Torr
(torr)
Pound-force
per square inch
(psi)
1 Pa = 1 N / m² 10-5 1.0197
x 10-5
9.8692
x 10-6
7.5006
x 10-3
145.04
x 10-6
1 Bar 100,000 = 106 dyn/cm² 1.0197 0.98692 750.06 14.504
1 at 98,066.50 0.980665 1 kgf / cm² 0.96784 735.56 14.223
1 atm 101,325 1.01325 1.0332 = 1 atm 760 14.696
1 torr 133.322 1.3332
x 10-3
1.3595
x 10-3
1.3158
x 10-3
= 1 Torr;
1 mm Hg
19.337
x 10-3
1 psi 6,894.76 68.948
x 10-3
70.307
x 10-3
68.046
x 10-3
51.715 = 1 lbf / in²
100 psi 0.7 Mn/M2 7 - - - 100