ATA means atmospheres absolute: the total pressure around you, counting the one atmosphere you already live in. A mild hyperbaric chamber runs at 1.3 ATA, about 4 to 4.4 psi above room pressure, roughly what you feel 10 feet under the sea. That is the level FDA-cleared soft chambers are built for. 1.5 ATA is about 7.3 psi and 2.0 ATA about 14.7 psi, and both cost more.
What ATA actually means
Pressure on a chamber spec sheet is quoted two ways, and brands mix them freely, which is why the numbers can look like they disagree.
ATA (atmospheres absolute) is the total pressure. Sitting on your couch at sea level you are at 1.0 ATA. A chamber at 1.3 ATA adds 0.3 of an atmosphere on top of that.
psi on a chamber page is almost always the extra pressure above the room, what a gauge reads. One atmosphere is about 14.7 psi, so 0.3 extra atmospheres is about 4.4 psi. Summit to Sea quotes 4.4 psi for its Dive and Grand Dive; Newtowne and OxyHealth round it to 4 psi. Same idea, slightly different rounding.
The easiest way to picture it is water depth. Every 33 feet of seawater adds one atmosphere. So 1.3 ATA feels like about 10 feet down, 1.5 ATA like about 16 feet, and 2.0 ATA like 33 feet, the bottom of a deep diving pool. Your ears notice the change the way they do when a plane comes down to land, and most people clear them the same way.
The home chamber pressure scale
Here is every chamber we compare, sorted by the highest pressure its maker lists. Prices were checked on November 11, 2026.
| Pressure | Above room | Feels like | Chambers in our list | Price range |
|---|---|---|---|---|
| 1.3 ATA | 4 to 4.4 psi | ~10 ft of seawater | Newtowne A4-34, Summit to Sea Dive, Grand Dive, Respiro 270, Vitaeris 320, OHS Oxy-Air 36 | $5,795 to $19,900 |
| 1.4 ATA | ~5.9 psi | ~13 ft | OxyNova 7 (and a 1.4 ATA option on the Oxy-Air 36) | $25,500 |
| 1.5 ATA | ~7.3 psi | ~16 ft | Skybaric Go, Skybaric Lounge, Recovery Outlet 34D | $11,999 to $27,900 |
| 2.0 ATA | ~14.7 psi | ~33 ft | Skybaric Pro, OxyLife MNS-2.0, OHS 30-inch, OHS 36-inch | $16,999 to $40,900 |
Two of the 2.0 ATA chambers are adjustable, which is worth knowing. OxyLife lets you set the MNS-2.0 anywhere from 1.1 to 2.0 ATA in 0.1 steps, and Oxygen Health Systems lists selectable settings on both hard shells (1.3 to 2.0 on the 36-inch; 1.3, 1.6, 1.8 or 2.0 on the 30-inch). A chamber that goes high can usually run low. The reverse is never true.
Why "mild" means 1.3 ATA
"Mild hyperbaric chamber" is not a marketing word someone made up last year. It comes from the way soft chambers reached the US market.
The soft chambers in our list that state FDA clearance (OxyHealth, Summit to Sea and Newtowne) all run at 1.3 ATA. The 510(k) summaries we read are explicit about what that clearance covers. Newtowne's (K051759) lists mild hyperbaria for the treatment of acute mountain sickness and its associated mild symptoms. Summit to Sea's (K072757) describes its Dive chambers as "mild hyperbaric chambers for pressures less than 5 PSI", with two relief valves set to 3.9 and 4 psi, intended to treat acute altitude sickness "as prescribed by or under the direction of a physician".
So the 1.3 ATA ceiling is built into the hardware. The relief valves open before the bag goes higher. That is part of why these chambers feel calm and simple to run: there is no dial to turn up.
The FDA's own letter on hyperbaric devices adds that HBOT devices are Class II medical devices cleared through the 510(k) process, and that cleared ones can be found by searching product code CBF in its database.
What higher pressure asks of the hardware
Each step up the scale changes the machine, not only the number on the gauge.
- The shell. At 1.3 ATA a urethane-coated fabric bag over a frame does the job. At 2.0 ATA you either move to steel (2.5 mm 304 stainless on both OHS hard shells, 2.0 mm on The Recovery Outlet's 1.5 ATA chamber) or to a soft chamber rated for it, like the TPU-bodied Skybaric Pro.
- The air supply. More pressure needs more air. Skybaric pairs the Pro with a 180 L/min compressor; OxyNova quotes a rotary vane compressor above 160 L/min for its 1.4 ATA chamber.
- The weight. A Skybaric Go is about 40 lb. The OHS 30-inch hard shell system is 507 lbs, the 36-inch 572 lbs. That changes your floor, your doorway and your delivery bill.
- The controls. Higher-pressure chambers come with more hardware to manage the session: dual gauges and emergency exhaust valves on the Skybaric range, interior and exterior pressure controls and an emergency alarm on the OHS hard shells.
What each step up costs
Read the price column of the table above from top to bottom and the pattern is clear, with one exception worth knowing about.
The cheapest chamber at 1.3 ATA is the Newtowne A4-34 at $5,795. The cheapest at 1.5 ATA is the Skybaric Go at $11,999, about twice as much, but with a concentrator and shipping included. The cheapest at 2.0 ATA is the Skybaric Pro at $16,999. Steel at 2.0 ATA starts at $35,490 (OHS 30-inch).
The exception is the soft 2.0 ATA chamber. Skybaric and OxyLife sell 2.0 ATA in fabric for $16,999 and $22,900, less than half of a steel chamber at the same rating. What you give up is warranty (one year on both entry packages) and the FDA wording: neither states 510(k) clearance, and OxyLife writes "FDA Listed", which is a registration, not a clearance.
Which pressure should you buy?
The honest answer is the one your doctor names. If they give you a number, buy a chamber that reaches it and stop there. If they say a mild chamber is fine, or do not mention pressure, a 1.3 ATA soft chamber with stated FDA clearance is the simple, well-trodden choice, and it leaves thousands of dollars in your pocket.
A few practical rules we would follow ourselves:
- Do not pay for 2.0 ATA "just in case". The jump from the A4-34 to the cheapest 2.0 ATA chamber is over $11,000.
- If you are unsure between 1.3 and higher, an adjustable chamber (OxyLife MNS-2.0) or a selectable hard shell keeps the door open, at a price.
- If a second person will run sessions too, check that the chamber can be operated from the inside. At higher pressure, the controls matter more.
Our 1.5 and 2.0 ATA ranking lines up the higher-pressure options, and the portable ranking covers the 1.3 ATA soft chambers.
A word on pressure and health claims
You will find a lot of promises attached to pressure numbers online. We do not repeat them. The FDA clearance we could read for the 1.3 ATA soft chambers covers acute mountain sickness. Anything else is a conversation between you and a doctor who knows your history, not something a pressure number on a product page can settle.
Nothing here is medical advice. A hyperbaric chamber is a medical device: talk to your doctor before you buy or use one, and follow the maker's instructions.
Our three picks for this guide
Newtowne Hyperbarics A4-34
The lowest price on an FDA-cleared soft chamber, with a 34-inch body that fits most bedrooms.
Read the review
Skybaric Go
A 1.5 ATA soft chamber with oxygen, free shipping and full remote control included.
Read the review
Skybaric Pro
A soft chamber that reaches 2.0 ATA, with a 15 L/min concentrator and touchscreens included.
Read the reviewWritten by Claire Benton, editor, home hyperbaric chambers, from the brands' own pages; prices checked November 11, 2026. Some links are affiliate links: if you buy through them, we may earn a commission at no extra cost to you. It never changes our scores. Disclosure.
