1. What is PSI to PSIA Conversion?

Definition: This calculator converts pressure from PSI (pounds per square inch gauge) to PSIA (pounds per square inch absolute).

Purpose: It helps engineers, technicians, and students convert between gauge pressure and absolute pressure measurements.

2. How Does the Conversion Work?

The conversion uses the formula:

Where:

• PSIA — Absolute pressure (includes atmospheric pressure)
• PSI — Gauge pressure (relative to atmospheric pressure)
• 14.7 — Standard atmospheric pressure at sea level (psi)

Explanation: Absolute pressure equals gauge pressure plus atmospheric pressure (approximately 14.7 psi at sea level).

3. Importance of PSI/PSIA Conversion

Details: Proper pressure measurement is critical in systems like HVAC, pneumatic controls, and industrial processes where absolute pressure matters.

4. Using the Calculator

Tips: Simply enter the PSI (gauge pressure) value and the calculator will output the equivalent PSIA (absolute pressure).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between PSI and PSIA?
A: PSI is gauge pressure (relative to atmospheric), while PSIA includes atmospheric pressure (absolute).

Q2: Why is 14.7 psi used for atmospheric pressure?
A: This is the average atmospheric pressure at sea level, though it varies with altitude and weather.

Q3: When would I need PSIA instead of PSI?
A: PSIA is used in scientific calculations, vacuum systems, and anywhere absolute pressure is required.

Q4: How does altitude affect this conversion?
A: At higher altitudes, atmospheric pressure decreases (less than 14.7 psi).

Q5: Can I convert PSIA back to PSI?
A: Yes, use the formula: PSI = PSIA - 14.7 (at sea level).