14.6 psia is equivalent to 0.1 psig.
Table of Contents
The conversion from psia (pounds per square inch absolute) to psig (pounds per square inch gauge) involves subtracting atmospheric pressure, which is approximately 14.5 psia at sea level. Since 14.6 psia is just slightly above atmospheric pressure, the resulting psig is a small positive value.
Conversion Tool
Result in psig:
Conversion Formula
The formula to convert psia to psig is:
psig = psia – atmospheric pressure
Atmospheric pressure at sea level is usually taken as 14.7 psia. This means psig measures pressure relative to atmospheric pressure, while psia measures absolute pressure including atmospheric.
Example:
- Given: 14.6 psia
- Subtract atmospheric pressure: 14.6 – 14.7 = -0.1 psig
- Result: -0.1 psig (a slight vacuum relative to atmospheric)
Conversion Example
- Convert 20 psia to psig
- 20 psia pressure is given
- Subtract atmospheric: 20 – 14.7 = 5.3 psig
- Result: 5.3 psig
- Convert 14.0 psia to psig
- 14.0 psia is given
- Subtract atmospheric: 14.0 – 14.7 = -0.7 psig
- Result: -0.7 psig (below atmospheric pressure)
- Convert 30 psia to psig
- 30 psia pressure is given
- Subtract atmospheric: 30 – 14.7 = 15.3 psig
- Result: 15.3 psig
- Convert 14.7 psia to psig
- 14.7 psia is atmospheric pressure
- Subtract atmospheric: 14.7 – 14.7 = 0 psig
- Result: 0 psig (atmospheric pressure baseline)
Conversion Chart
This chart shows values in psia converted to psig by subtracting 14.7. Negative psig values indicate pressure below atmospheric pressure (vacuum), positive values indicate pressure above atmospheric.
| psia | psig |
|---|---|
| -10.4 | -25.1 |
| -5.0 | -19.7 |
| 0.0 | -14.7 |
| 5.0 | -9.7 |
| 10.0 | -4.7 |
| 14.6 | -0.1 |
| 20.0 | 5.3 |
| 25.0 | 10.3 |
| 30.0 | 15.3 |
| 35.0 | 20.3 |
| 39.6 | 24.9 |
Related Conversion Questions
- How do I convert 14.6 psia into psig for a pressure gauge?
- What is the psig equivalent of 14.6 psia at sea level?
- Why does 14.6 psia result in a negative or near zero psig?
- Can I use 14.6 psia as atmospheric pressure when calculating psig?
- How to interpret a psig reading if the psia is 14.6?
- Is 14.6 psia above or below atmospheric pressure in psig terms?
- What formula converts 14.6 psia to psig for HVAC applications?
Conversion Definitions
psia: Pounds per square inch absolute (psia) measures pressure relative to a perfect vacuum. It includes atmospheric pressure, so it shows total pressure exerted, including air pressure at sea level. This unit used in science and engineering when absolute pressure is needed.
psig: Pounds per square inch gauge (psig) measures pressure relative to atmospheric pressure. A psig reading of zero means pressure equals atmospheric. Positive psig means pressure above atmosphere, negative means below. Gauge pressure useful in many practical applications like tires and pipelines.
Conversion FAQs
Why does subtracting 14.7 from psia gives psig?
Because atmospheric pressure at sea level is approximately 14.7 psi absolute, gauge pressure measures pressure above or below this atmospheric baseline. Subtracting 14.7 psi from an absolute pressure isolates the pressure difference relative to atmosphere, giving gauge pressure.
What happens if psia is less than 14.7?
If psia is less than 14.7, the gauge pressure becomes negative, indicating a vacuum or pressure below atmospheric. This occurs inside vacuum systems or sealed containers where pressure is reduced below atmospheric pressure.
Is psig always positive?
No, psig can be negative when the absolute pressure is less than atmospheric pressure. This negative gauge pressure represents vacuum conditions relative to atmospheric pressure, common in suction or vacuum processes.
Can atmospheric pressure vary affect conversions?
Yes, atmospheric pressure changes with altitude and weather. The standard 14.7 psia is an average at sea level, so at higher altitudes or different conditions, the exact conversion from psia to psig may differ slightly.
Why use psig instead of psia in some fields?
Psig is useful when interested only in pressure relative to the surrounding atmosphere, like tire pressure or water system pressure. Psia includes atmospheric pressure, which is unnecessary in many practical applications, making psig more convenient to interpret.