Standard Atmospheres to Gigapascals (atm to GPa)
1 standard atmosphere equals 0.000101325 gigapascals exactly.
How to convert standard atmospheres to gigapascals
To convert standard atmospheres to gigapascals, multiply the number of standard atmospheres by 0.000101325. This factor is exact. To go the other way, multiply gigapascals by 9,869.232667 (rounded).
gigapascals = standard atmospheres × 0.000101325
Example: 10 standard atmospheres = 0.00101325 gigapascals.
About these units
Standard Atmosphere (atm)
Exactly 101,325 pascals, the average pressure of the atmosphere at sea level.
A column of mercury about 76 cm tall was Torricelli's measure of the air, and the standard atmosphere began as exactly that: the pressure of 760 mm of mercury at 0 degrees Celsius under standard gravity. It was used as a reference for physical and chemical properties, and the Celsius scale set 100 degrees as the boiling point of water at that pressure.
In 1954 the 10th CGPM confirmed the standard atmosphere as exactly 1,013,250 dynes per square centimeter, which is 101,325 pascals, a definition that no longer depends on the properties of any substance.
In practice one atmosphere is about 1.01325 bar, 760 mmHg, 14.696 psi or 29.92 inHg, and roughly the pressure of 10.33 meters of water. Chemistry splits on it: until 1982 standard temperature and pressure used 1 atm, but that year IUPAC recommended a standard pressure of exactly 100 kPa instead.
1 standard atmosphere = 101,325 pascals (exactly).
Sources: Wikipedia: Standard atmosphere (unit); Wikipedia: Atmospheric pressure; Wikipedia: Evangelista Torricelli
Gigapascal (GPa)
One billion pascals. Used for the stiffness (Young's modulus) of materials; steel is about 200 GPa.
Blaise Pascal's name was attached to the SI unit of pressure in 1971, when the 14th General Conference on Weights and Measures adopted it for one newton per square metre. A gigapascal is a billion of them, 10^9 Pa, which is a size that makes sense only for solid materials and deep-Earth conditions, not for weather or tyres.
Materials scientists quote stiffness in it. Wikipedia's table of Young's modulus lists structural steel at about 200 GPa and diamond at 1,220 GPa, while geophysicists use gigapascals for tectonic stresses and pressures inside the planet. Atmospheric pressure of about 101,325 Pa is therefore about 0.0001 GPa, and one gigapascal is roughly 145,000 psi or 145 ksi. A gigapascal also equals one thousand megapascals, the unit in which concrete and steel strengths are usually written.
1 gigapascal = 1,000,000,000 pascals (exactly).
Sources: Wikipedia: Pascal (unit); Wikipedia: Pounds per square inch
Related conversions
- Gigapascals to standard atmospheres (reverse)
- Standard atmospheres to pascals
- Standard atmospheres to kilopascals
- Standard atmospheres to bars
- Standard atmospheres to PSI
- Standard atmospheres to hectopascals
- Standard atmospheres to megapascals
- Standard atmospheres to millibars
- Standard atmospheres to torr
- Standard atmospheres to millimeters of mercury
- Standard atmospheres to inches of mercury
- Standard atmospheres to kilopounds per square inch
- Standard atmospheres to millimeters of water
- Pascals to gigapascals
- Kilopascals to gigapascals
- Bars to gigapascals
- PSI to gigapascals
See all pressure units.