1. What Is Surface Air Consumption Rate?

The Surface Air Consumption (SAC) rate measures how much air a diver consumes at the surface, providing a standardized way to compare air consumption between dives and divers. It helps in dive planning and air management.

2. How Does The Calculator Work?

The calculator uses the SAC rate formula:

Where:

• \( Surface Pressure Used \) — Air consumed during dive (psi)
• \( Dive Time \) — Total dive duration (minutes)
• \( Avg Depth \) — Average depth in atmospheres absolute (ATA)

Explanation: The formula normalizes air consumption to surface conditions by accounting for depth pressure, allowing comparison across different dive profiles.

3. Importance Of SAC Calculation

Details: Calculating SAC rate is essential for dive planning, estimating air requirements for future dives, identifying changes in air consumption, and improving diving efficiency and safety.

4. Using The Calculator

Tips: Enter surface pressure used in psi, dive time in minutes, and average depth in atmospheres absolute. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical SAC rate for recreational divers?
A: Most recreational divers have SAC rates between 15-25 psi/min, but this varies based on experience, fitness, and conditions.

Q2: How can I improve my SAC rate?
A: Improve buoyancy control, reduce unnecessary movements, maintain proper trim, and practice relaxed breathing techniques.

Q3: Why convert depth to ATA?
A: ATA (atmospheres absolute) accounts for the increased pressure at depth, allowing accurate normalization of air consumption to surface conditions.

Q4: Does SAC rate change with experience?
A: Yes, experienced divers typically have lower SAC rates due to better technique, comfort in the water, and efficient movement.

Q5: How do I calculate ATA from depth?
A: ATA = (Depth in feet / 33) + 1 for salt water, or (Depth in feet / 34) + 1 for fresh water.