Hyperbaric · 4 min read
Understanding ATA: What the Pressure Numbers Mean
ATA (atmospheres absolute) is a unit of total pressure measured relative to a vacuum, where everyday sea-level air pressure equals 1.0 ATA.
Quick answer
- 1.0 ATA is normal sea-level pressure; 1.3 ATA is about 30% higher, 1.5 ATA about 50% higher, and 2.0 ATA is double.
- Mild wellness use typically stays in the 1.3–1.5 ATA range.
- A chamber's maximum rated ATA helps you match it to your space and intended use.
When you compare hyperbaric chambers you'll see pressures listed in ATA. Here's a simple explanation of what those numbers describe.
ATA in plain terms
ATA stands for 'atmospheres absolute.' It measures total pressure relative to a vacuum. At sea level, the air around you is about 1.0 ATA.
A chamber rated at 1.3 ATA holds pressure roughly 30% above sea level; 1.5 ATA is about 50% above; 2.0 ATA is double sea-level pressure.
Why the range matters
Higher pressure means more oxygen dissolves into the body's fluids. Mild wellness use typically stays in the 1.3–1.5 ATA range, while higher pressures are associated with professional, clinical-grade equipment.
Knowing a chamber's maximum rated pressure helps you match it to your intended use and confirm it fits the space and operating routine you have in mind.
Common questions
Is a higher ATA always better?
Not necessarily — 'better' depends on your goals, the equipment's design, and how it will be used. Mild wellness use commonly stays in the 1.3–1.5 ATA range.