A technical atmosphere (symbol: at) is a non-SI unit of pressure equal to 1 kilogram-force per square centimeter, i.e. 98.0665 kilopascals (kPa) or about 0.967 84 standard atmospheres. The symbol "at" clashes with that of the katal (symbol: "kat"), the SI unit of catalytic activity; a kilotechnical atmosphere would have the symbol "kat", indistinguishable from the symbol for the katal.
pascal (Pa) |
bar (bar) |
technical atmosphere (at) |
atmosphere (atm) |
torr (Torr) |
pound-force per square inch (psi) |
|
|---|---|---|---|---|---|---|
| 1 Pa | ≡ 1 N/m2 | 10−5 | 1.0197×10−5 | 9.8692×10−6 | 7.5006×10−3 | 145.04×10−6 |
| 1 bar | 100,000 | ≡ 106 dyn/cm2 | 1.0197 | 0.98692 | 750.06 | 14.504 |
| 1 at | 98,066.5 | 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 | 1.3332×10−3 | 1.3595×10−3 | 1.3158×10−3 | ≡ 1 Torr; = 1 mmHg | 19.337×10−3 |
| 1 psi | 6,894.76 | 68.948×10−3 | 70.307×10−3 | 68.046×10−3 | 51.715 | ≡ 1 lbf/in2 |
Example reading: 1 Pa = 1 N/m2 = 10−5 bar = 10.197×10−6 at = 9.8692×10−6 atm, etc.
Note: mmHg is an abbreviation for millimetres of mercury.
External links
- NIST Guide for the Use of the International System of Units (SI), Appendix B: Conversion Factors
