Atmosphere (atm) - Pressure Unit - Definition, Application, Conversions

What is the atmosphere (atm)?

The atmosphere is a unit of pressure that was originally defined as the pressure exerted by a column of mercury 760 millimetres high at 0 degrees Celsius at normal Earth acceleration.  Its designation for the pressure unit of the atmosphere is atm.

One atm corresponds to the atmospheric pressure on Earth at sea level and is equivalent to 101 325 pascals (Pa) in the SI system.

Atmosphere is used less frequently than bar or pascal in industrial hoses but still finds application in some technical specifications. In industry, the atmosphere is used to define working pressures in hose systems, especially where pressures are compared to atmospheric pressure. It's crucial that working pressures in hoses are appropriately matched to atmospheric pressure.

When are atmospheres used to measure pressure?

Atmospheres are used to measure pressure less and less frequently because they have been superseded by other units. However, they sometimes appear in the following fields:

• Meteorology - Atmospheres are used to measure atmospheric pressure. This is particularly important in climate research and weather forecasting, where changes in pressure can indicate upcoming weather changes. 
• Diving and underwater work - In diving, the atmosphere is the key unit for determining dive depth and planning decompression time. This is important because water pressure increases by one atmosphere every 10 metres or so of depth. 
• Aviation and aerospace - Atmosphere is used to determine cabin pressures in aircraft and spacecraft, which is crucial for the safety and comfort of crew and passengers. 
• Engineering and design - In engineering, particularly in the design of underwater equipment, the atmosphere is used to simulate environmental conditions and test pressure resistance. 
• Medicine - The atmosphere is used to determine pressure levels in hyperbaric chambers, which are used to treat a variety of conditions and injuries.
• Science and research - In scientific experiments, particularly in physics and chemistry, the atmosphere is used as a reference in studies on the behaviour of gases and liquids at different pressures.

How to measure pressure in atmospheres?

To measure pressure in physical atmospheres (atm), use a manometer that is calibrated in this unit or in units that can be easily converted to atm.

1. Choose the right manometer - The most common device for measuring pressure is a mechanical or digital manometer. Some of these devices have the ability to set the scale directly in atmospheres (atm), which makes it easier to read directly.
2. Identify the measuring point - Determine the place where you want to measure the pressure (e.g. in a gas system, in a plumbing system or in a gas tank).
3. Connect the manometer - Make sure that the manometer is properly connected to the measuring point. The tightness of the connection is crucial for the accuracy of the reading.
4. Read the result - In a mechanical manometer, the pressure will be indicated by the dial of the device. In a digital manometer, the result will appear on the display.

If your device measures pressure in other pressure units, you can convert it to physical atmospheres using the appropriate pressure units conversions.

Conversion of pressure unit atmosphere (atm)

• 1 atm = 1,01325 bar
• 1 atm = 101 325 Pa
• 1 atm = 1013,25 hPa
• 1 atm = 101,325 kPa
• 1 atm = 0,101325 MPa
• 1 atm = 14,6959 PSI
• 1 atm = 10 332,274 mmH2O
• 1 atm = 406,782 inH2O
• 1 atm = 760 Tr
• 1 atm = 760 mmHg
• 1 atm = 29,9213 inHg
• 1 atm = 2116,22 PSF
• 1 atm = 1,03323 at
  

1 atmosphere (atm) = 1,01325 bar = 101 325 Pa = 1013,25 hPa = 101,325 kPa = 0,101325 MPa = 14,6959 PSI = 10 332,274 mmH2O = 406,782 inH2O = 760 Tr = 760 mmHg = 29,9213 inHg = 2116,22 PSF = 1,03323 at

atm to Bar - Atmosphere to Bar pressure unit conversion

To convert pressure from Atmosphere (atm) to Bar multiply the pressure in Atmosphere (atm) by 1,01325.

• 1 atm to bar? 1 atm is equal to 1,01325 bar
• 2 atm to bar? 2 atm is equal to 2,0265 bar
• 3 atm to bar? 3 atm is equal to 3,03975 bar
• 4 atm to bar? 4 atm is equal to 4,053 bar
• 5 atm to bar? 5 atm is equal to 5,06625 bar
• 6 atm to bar? 6 atm is equal to 6,0795 bar
• 7 atm to bar? 7 atm is equal to 7,09275 bar
• 8 atm to bar? 8 atm is equal to 8,106 bar
• 9 atm to bar? 9 atm is equal to 9,11925 bar
• 10 atm to bar? 10 atm is equal to 10,1325 bar
• 20 atm to bar? 20 atm is equal to 20,265 bar
• 50 atm to bar? 50 atm is equal to 50,6625 bar
• 100 atm to bar? 100 atm is equal to 101,325 bar
• 200 atm to bar? 200 atm is equal to 202,65 bar
• 500 atm to bar? 500 atm is equal to 506,625 bar
• 1000 atm to bar? 1000 atm is equal to 1013,25 bar

atm to Pa - Atmosphere to Pascal pressure unit conversion

To convert pressure from Atmosphere (atm) to Pascal (Pa) multiply the pressure in Atmosphere (atm) by 101325.

• 1 atm to Pa? 1 atm is equal to 101325 Pa
• 1,1 atm to Pa? 1,1 atm is equal to 111457,5 Pa
• 1,2 atm to Pa? 1,2 atm is equal to 121590 Pa
• 1,25 atm to Pa? 1,25 atm is equal to 126656,25 Pa
• 1,3 atm to Pa? 1,3 atm is equal to 131722,5 Pa
• 2 atm to Pa? 2 atm is equal to 202650 Pa
• 5 atm to Pa? 5 atm is equal to 506625 Pa
• 10 atm to Pa? 10 atm is equal to 1013250 Pa
• 20 atm to Pa? 20 atm is equal to 2026500 Pa
• 50 atm to Pa? 50 atm is equal to 5066250 Pa
• 100 atm to Pa? 100 atm is equal to 10132500 Pa
• 200 atm to Pa? 200 atm is equal to 20265000 Pa
• 500 atm to Pa? 500 atm is equal to 50662500 Pa
• 1000 atm to Pa? 1000 atm is equal to 101325000 Pa

atm to hPa - Atmosphere to Hectopascal pressure unit conversion

To convert pressure from Atmosphere (atm) to Hectopascal (hPa) multiply the pressure in Atmosphere (atm) by 1013,25.

• 1 atm to hPa? 1 atm is equal to 1013,25 hPa
• 2 atm to hPa? 2 atm is equal to 2026,5 hPa
• 5 atm to hPa? 5 atm is equal to 5066,25 hPa
• 10 atm to hPa? 10 atm is equal to 10132,5 hPa
• 20 atm to hPa? 20 atm is equal to 20265 hPa
• 50 atm to hPa? 50 atm is equal to 50662,5 hPa
• 100 atm to hPa? 100 atm is equal to 101325 hPa
• 200 atm to hPa? 200 atm is equal to 202650 hPa
• 500 atm to hPa? 500 atm is equal to 506625 hPa
• 1000 atm to hPa? 1000 atm is equal to 1013250 hPa

atm to kPa - Atmosphere to Kilopascal pressure unit conversion

To convert pressure from Atmosphere (atm) to Kilopascal (kPa) multiply the pressure in Atmosphere (atm) by 101,325.

• 1 atm to kPa? 1 atm is equal to 101,325 kPa
• 2 atm to kPa? 2 atm is equal to 202,65 kPa
• 5 atm to kPa? 5 atm is equal to 506,625 kPa
• 10 atm to kPa? 10 atm is equal to 1013,25 kPa
• 20 atm to kPa? 20 atm is equal to 2026,5 kPa
• 50 atm to kPa? 50 atm is equal to 5066,25 kPa
• 100 atm to kPa? 100 atm is equal to 10132,5 kPa
• 200 atm to kPa? 200 atm is equal to 20265 kPa
• 500 atm to kPa? 500 atm is equal to 50662,5 kPa
• 1000 atm to kPa? 1000 atm is equal to 101325 kPa

atm to MPa - Atmosphere to Megapascal pressure unit conversion

To convert pressure from Atmosphere (atm) to Megapascal (MPa) multiply the pressure in Atmosphere (atm) by 0,101325.

• 1 atm to MPa? 1 atm is equal to 0,101325 MPa
• 2 atm to MPa? 2 atm is equal to 0,20265 MPa
• 5 atm to MPa? 5 atm is equal to 0,506625 MPa
• 10 atm to MPa? 10 atm is equal to 1,01325 MPa
• 20 atm to MPa? 20 atm is equal to 2,0265 MPa
• 50 atm to MPa? 50 atm is equal to 5,06625 MPa
• 100 atm to MPa? 100 atm is equal to 10,1325 MPa
• 200 atm to MPa? 200 atm is equal to 20,265 MPa
• 500 atm to MPa? 500 atm is equal to 50,6625 MPa
• 1000 atm to MPa? 1000 atm is equal to 101,325 MPa

atm to PSI - Atmosphere to PSI pressure unit conversion

To convert pressure from Atmosphere (atm) to PSI multiply the pressure in Atmosphere (atm) by 14,6959.

• 1 atm to PSI? 1 atm is equal to 14,6959 PSI
• 2 atm to PSI? 2 atm is equal to 29,3918 PSI
• 2,5 atm to PSI? 2,5 atm is equal to 36,73975 PSI
• 5 atm to PSI? 5 atm is equal to 73,4795 PSI
• 10 atm to PSI? 10 atm is equal to 146,959 PSI
• 20 atm to PSI? 20 atm is equal to 293,918 PSI
• 50 atm to PSI? 50 atm is equal to 734,795 PSI
• 100 atm to PSI? 100 atm is equal to 1469,59 PSI
• 200 atm to PSI? 200 atm is equal to 2939,18 PSI
• 500 atm to PSI? 500 atm is equal to 7347,95 PSI
• 1000 atm to PSI? 1000 atm is equal to 14695,9 PSI

atm to mmH2O - Atmosphere to Milimetre of water column pressure unit conversion

To convert pressure from Atmosphere (atm) to Milimetre of water column (mmH2O) multiply the pressure in Atmosphere (atm) by 10332,274.

• 1 atm to mmH2O? 1 atm is equal to 10332,274 mmH2O
• 2 atm to mmH2O? 2 atm is equal to 20664,548 mmH2O
• 5 atm to mmH2O? 5 atm is equal to 51661,37 mmH2O
• 10 atm to mmH2O? 10 atm is equal to 103322,74 mmH2O
• 20 atm to mmH2O? 20 atm is equal to 206645,48 mmH2O
• 50 atm to mmH2O? 50 atm is equal to 516613,7 mmH2O
• 100 atm to mmH2O? 100 atm is equal to 1033227,4 mmH2O
• 200 atm to mmH2O? 200 atm is equal to 2066454,8 mmH2O
• 500 atm to mmH2O? 500 atm is equal to 5166137 mmH2O
• 1000 atm to mmH2O? 1000 atm is equal to 10332274 mmH2O

atm to inH2O - Atmosphere to Inch of water column pressure unit conversion

To convert pressure from Atmosphere (atm) to Inch of water column (inH2O) multiply the pressure in Atmosphere (atm) by 406,782.

• 1 atm to inH2O? 1 atm is equal to 406,782 inH2O
• 2 atm to inH2O? 2 atm is equal to 813,564 inH2O
• 5 atm to inH2O? 5 atm is equal to 2033,91 inH2O
• 10 atm to inH2O? 10 atm is equal to 4067,82 inH2O
• 20 atm to inH2O? 20 atm is equal to 8135,64 inH2O
• 50 atm to inH2O? 50 atm is equal to 20339,1 inH2O
• 100 atm to inH2O? 100 atm is equal to 40678,2 inH2O
• 200 atm to inH2O? 200 atm is equal to 81356,4 inH2O
• 500 atm to inH2O? 500 atm is equal to 203391 inH2O
• 1000 atm to inH2O? 1000 atm is equal to 406782 inH2O

atm to torr - Atmosphere to torr pressure unit conversion

To convert pressure from Atmosphere (atm) to torr (Tr) multiply the pressure in Atmosphere (atm) by 760.

• 1 atm to torr? 1 atm is equal to 760 torr
• 1,25 atm to torr? 1,25 atm is equal to 950 torr
• 2 atm to torr? 2 atm is equal to 1520 torr
• 5 atm to torr? 5 atm is equal to 3800 torr
• 10 atm to torr? 10 atm is equal to 7600 torr
• 20 atm to torr? 20 atm is equal to 15200 torr
• 50 atm to torr? 50 atm is equal to 38000 torr
• 100 atm to torr? 100 atm is equal to 76000 torr
• 200 atm to torr? 200 atm is equal to 152000 torr
• 500 atm to torr? 500 atm is equal to 380000 torr
• 715 atm to torr? 715 atm is equal to 543400 torr
• 1000 atm to torr? 1000 atm is equal to 760000 torr

atm to mmHg - Atmosphere to Milimetre of mercury column pressure unit conversion

To convert pressure from Atmosphere (atm) to Milimetre of mercury column (mmHg) multiply the pressure in Atmosphere (atm) by 760.

• 1 atm to mmHg? 1 atm is equal to 760 mmHg
• 1,07 atm to mmHg? 1,07 atm is equal to 813,2 mmHg
• 1,2 atm to mmHg? 1,2 atm is equal to 912 mmHg
• 1,25 atm to mmHg? 1,25 atm is equal to 950 mmHg
• 1,25 atm to mmHg? 1,25 atm is equal to 950 mmHg
• 1,5 atm to mmHg? 1,5 atm is equal to 1140 mmHg
• 2 atm to mmHg? 2 atm is equal to 1520 mmHg
• 2,3 atm to mmHg? 2,3 atm is equal to 1748 mmHg
• 2,5 atm to mmHg? 2,5 atm is equal to 1900 mmHg
• 5 atm to mmHg? 5 atm is equal to 3800 mmHg
• 10 atm to mmHg? 10 atm is equal to 7600 mmHg
• 20 atm to mmHg? 20 atm is equal to 15200 mmHg
• 50 atm to mmHg? 50 atm is equal to 38000 mmHg
• 100 atm to mmHg? 100 atm is equal to 76000 mmHg
• 200 atm to mmHg? 200 atm is equal to 152000 mmHg
• 500 atm to mmHg? 500 atm is equal to 380000 mmHg
• 633 atm to mmHg? 633 atm is equal to 481080 mmHg
• 1000 atm to mmHg? 1000 atm is equal to 760000 mmHg

atm to inHg - Atmosphere to Inch of mercury column pressure unit conversion

To convert pressure from Atmosphere (atm) to Inch of mercury column (inHg) multiply the pressure in Atmosphere (atm) by 29,9213.

• 1 atm to inHg? 1 atm is equal to 29,9213 inHg
• 2 atm to inHg? 2 atm is equal to 59,8426 inHg
• 5 atm to inHg? 5 atm is equal to 149,6065 inHg
• 10 atm to inHg? 10 atm is equal to 299,213 inHg
• 20 atm to inHg? 20 atm is equal to 598,426 inHg
• 50 atm to inHg? 50 atm is equal to 1496,065 inHg
• 100 atm to inHg? 100 atm is equal to 2992,13 inHg
• 200 atm to inHg? 200 atm is equal to 5984,26 inHg
• 500 atm to inHg? 500 atm is equal to 14960,65 inHg
• 1000 atm to inHg? 1000 atm is equal to 29921,3 inHg

atm to PSF - Atmosphere to PSF pressure unit conversion

To convert pressure from Atmosphere (atm) to PSF multiply the pressure in Atmosphere (atm) by 2116,22.

• 1 atm to PSF? 1 atm is equal to 2116,22 PSF
• 2 atm to PSF? 2 atm is equal to 4232,44 PSF
• 5 atm to PSF? 5 atm is equal to 10581,1 PSF
• 10 atm to PSF? 10 atm is equal to 21162,2 PSF
• 20 atm to PSF? 20 atm is equal to 42324,4 PSF
• 50 atm to PSF? 50 atm is equal to 105811 PSF
• 100 atm to PSF? 100 atm is equal to 211622 PSF
• 200 atm to PSF? 200 atm is equal to 423244 PSF
• 500 atm to PSF? 500 atm is equal to 1058110 PSF
• 1000 atm to PSF? 1000 atm is equal to 2116220 PSF

atm to at - Atmosphere to Technical atmosphere pressure unit conversion

To convert pressure from Atmosphere (atm) to Technical Atmosphere (at) multiply the pressure in Atmosphere (atm) by 1,03323.

• 1 atm to at? 1 atm is equal to 1,03323 at
• 2 atm to at? 2 atm is equal to 2,06646 at
• 5 atm to at? 5 atm is equal to 5,16615 at
• 10 atm to at? 10 atm is equal to 10,3323 at
• 20 atm to at? 20 atm is equal to 20,6646 at
• 50 atm to at? 50 atm is equal to 51,6615 at
• 100 atm to at? 100 atm is equal to 103,323 at
• 200 atm to at? 200 atm is equal to 206,646 at
• 500 atm to at? 500 atm is equal to 516,615 at
• 1000 atm to at? 1000 atm is equal to 1033,23 at