1. What is PSIG to PSIA Conversion?

The PSIG to PSIA conversion calculates absolute pressure from gauge pressure by adding atmospheric pressure (14.696 psi at sea level). PSIG measures pressure relative to atmospheric pressure, while PSIA measures pressure relative to absolute vacuum.

2. How Does the Calculator Work?

The calculator uses the PSIG to PSIA formula:

Where:

• \( PSIA \) — Absolute pressure in pounds per square inch absolute
• \( PSIG \) — Gauge pressure in pounds per square inch gauge
• \( 14.696 \) — Standard atmospheric pressure at sea level in psi

Explanation: This formula converts gauge pressure (pressure relative to atmospheric) to absolute pressure (pressure relative to perfect vacuum).

3. Importance of Pressure Conversion

Details: Accurate pressure conversion is crucial for engineering calculations, fluid dynamics, HVAC systems, and scientific research where absolute pressure values are required for precise measurements and calculations.

4. Using the Calculator

Tips: Enter gauge pressure in PSIG. The calculator will automatically compute the absolute pressure in PSIA by adding standard atmospheric pressure (14.696 psi).

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between PSIG and PSIA?
A: PSIG is gauge pressure measured relative to atmospheric pressure, while PSIA is absolute pressure measured relative to perfect vacuum. PSIA = PSIG + atmospheric pressure.

Q2: Why is 14.696 psi used for atmospheric pressure?
A: This is the standard atmospheric pressure at sea level under standard conditions. Actual atmospheric pressure may vary with altitude and weather conditions.

Q3: When should I use PSIA instead of PSIG?
A: Use PSIA for scientific calculations, gas laws, and applications where absolute pressure is required. Use PSIG for most industrial and mechanical applications where gauge pressure is sufficient.

Q4: How does altitude affect the conversion?
A: At higher altitudes, atmospheric pressure decreases, so the conversion factor would be less than 14.696 psi. This calculator uses standard sea-level atmospheric pressure.

Q5: Can this calculator handle negative PSIG values?
A: Yes, negative PSIG values (vacuum conditions) can be entered and will result in PSIA values less than atmospheric pressure.