1 atm is equal to approximately 14.6959 psia.
The atmosphere (atm) unit measures pressure based on Earth’s atmospheric pressure at sea level, whereas psia (pounds per square inch absolute) includes atmospheric pressure plus any additional pressure. Therefore, converting 1 atm to psia gives the absolute pressure equivalent in psi units.
Conversion Tool
Result in psia:
Conversion Formula
To convert atmospheres (atm) to pounds per square inch absolute (psia), multiply the atm value by 14.6959. This is because 1 atm is defined as 14.6959 psi at sea level pressure. Psia measures absolute pressure, including atmospheric pressure, so the conversion factor directly relates these units.
Formula:
psia = atm × 14.6959
For example, converting 1 atm:
psia = 1 × 14.6959 = 14.6959 psia
Conversion Example
- Convert 2 atm to psia:
- Multiply 2 by 14.6959
- 2 × 14.6959 = 29.3918 psia
- Result: 2 atm = 29.3918 psia
- Convert 0.5 atm to psia:
- Multiply 0.5 by 14.6959
- 0.5 × 14.6959 = 7.34795 psia
- Result: 0.5 atm = 7.34795 psia
- Convert 3.2 atm to psia:
- Multiply 3.2 by 14.6959
- 3.2 × 14.6959 = 47.027 psia
- Result: 3.2 atm = 47.027 psia
- Convert 10 atm to psia:
- Multiply 10 by 14.6959
- 10 × 14.6959 = 146.959 psia
- Result: 10 atm = 146.959 psia
Conversion Chart
The following table shows pressures from -24.0 atm to 26.0 atm converted to psia. Negative values are hypothetical and indicate pressures below vacuum, which physically impossible. Use the chart to quickly find psia equivalent by multiplying atm values by 14.6959.
| atm | psia | atm | psia |
|---|---|---|---|
| -24.0 | -352.7016 | 2.0 | 29.3918 |
| -20.0 | -293.918 | 6.0 | 88.1754 |
| -16.0 | -235.1344 | 10.0 | 146.959 |
| -12.0 | -176.3508 | 14.0 | 205.7426 |
| -8.0 | -117.5672 | 18.0 | 264.5262 |
| -4.0 | -58.7836 | 22.0 | 323.3098 |
| 0.0 | 0 | 26.0 | 382.0934 |
Related Conversion Questions
- How many psia is 1 atm equal to?
- What is the formula to convert 1 atm into psia?
- Does 1 atm pressure always equal 14.7 psia?
- Why does the conversion from atm to psia matter for pressure measurements?
- Can 1 atm be converted directly to psia without adjustments?
- Is 1 atm the same as 1 psia?
- How to convert 1 atm to absolute pressure in psi units?
Conversion Definitions
atm: Atmosphere (atm) is a pressure unit representing the standard atmospheric pressure at sea level, defined as 101325 Pascals. It provides a reference for measuring pressure relative to Earth’s atmosphere, commonly used in chemistry and physics to express gas pressures.
psia: Pounds per square inch absolute (psia) measures absolute pressure relative to vacuum. It includes atmospheric pressure plus any additional pressure applied. Unlike gauge pressure, psia represents the total pressure exerted on a system measured in psi units.
Conversion FAQs
What is the difference between psia and psig when converting from atm?
Psia includes atmospheric pressure plus any applied pressure, while psig (pounds per square inch gauge) only measures pressure above atmospheric pressure. When converting atm, which is absolute pressure, to psia, the result includes atmospheric pressure, but converting to psig requires subtracting atmospheric pressure.
Can atmospheric pressure vary and affect the conversion from atm to psia?
Yes, atmospheric pressure changes with altitude and weather conditions. The standard 1 atm equals 14.6959 psia is based on sea level average conditions. In locations with different atmospheric pressure, the absolute pressure in psia for 1 atm might slightly vary in practical cases.
Why use psia instead of atm in engineering applications?
Psia provides pressure measurement in units compatible with mechanical systems using pounds-force and inches, common in the US. It also directly expresses absolute pressure, which is critical in vacuum systems and high-pressure environments, whereas atm is more common in scientific contexts.
Is converting atm to psia always a linear calculation?
Yes, conversion from atm to psia is linear because both are units measuring absolute pressure. Multiplying by the constant 14.6959 converts between them directly without adjustments for temperature or other variables.
How precise is the conversion factor 14.6959 for atm to psia?
The factor 14.6959 is based on standard atmospheric pressure at sea level, accurate for most engineering and scientific uses. Slight variations may occur due to local atmospheric changes, but for general conversion, it provides sufficient precision.