Pressure Ranges and Pressure Units Overview
| Pressure Range |
Absolute pressure in mbar |
Molecules per cm3 |
Mean free path |
| |
| Athmosphere |
1.013 |
2,7 x 1019 |
68 nm |
 |
| Rough vacuum |
300 ... 1 |
1019 ... 1016 |
0.1 ... 100 µm |
|
| Medium vacuum |
1 ... 10-3 |
1016 ... 1013 |
0.1 ... 100 mm |
|
| High vacuum (HV) |
10-3 ... 10-7 |
1013 ... 109 |
10 cm ... 1 km |
|
| Ultra high vacuum (UHV) |
10-7 ... 10-11 |
109 ... 105 |
1 km ... 104 km |
|
| Extreme ultra high vacuum (XUHV) |
< 10-11 |
< 105 |
> 104 km |
|
|
1 mbar = 0.1 kP = 1hPa = 0.75 torr = 0.75 mmHg
1 torr = 1 mmHg = 133 Pa = 1.33 mbar
760 torr = 1 atm = 1013 mbar
1 micron = 1 mTorr = 0.133 Pa = 1.33E-3 mbar
1 psi = 6895 Pa = 69 mbar = 51.7 Torr
1 atm = 760 Torr = 1013 hPa = 1013 mbar = 14.7 psi
