Why this table exists. Published hyperbaric work does not use one interchangeable exposure. Pressure, breathing gas, oxygen fraction, delivery interface, session design and the people studied all differ. Putting those beside each citation lets a reader check whether a study resembles the chamber in front of them. A 2.5 ATA, 100% oxygen protocol with scheduled air breaks is not evidence about a 1.3 ATA fabric chamber fed by a concentrator, and this table is arranged so that is obvious rather than arguable.
The pressure column reports what each publication stated. We do not convert a protocol into a claim about different hardware. Sort by any column; filter by category.
Cited research, not medical advice. This is an equipment-research reference. It is not a treatment guide, not a recommendation for any person, and nothing in it states that a hyperbaric chamber treats any condition. Hyperbaric Service Pros installs and services chambers and sells equipment.
01
Citation table
40 of 40 citations shown
| Category | Type | Reported pressure | Reported finding | Why it matters for equipment | |||
|---|---|---|---|---|---|---|---|
| Pressure & physiology | Physiology of hyperbaric hyperoxia | 1999 | review | Not stated | Not stated | This review covers pulmonary gas exchange, oxygen transport, tissue oxygen use, and circulatory responses during hyperbaric hyperoxia. | Pressure and inspired oxygen fraction are separate equipment variables that should be identified rather than treated as one specification. |
| Pressure & physiology | Alveolar-arterial O2 differences in man at 0.2, 1.0, 2.0, and 3.5 Ata inspired PO2 | 1971 | cohort | 0.2-3.5 ATA | Not stated | The human study measured alveolar-arterial oxygen differences at inspired oxygen partial pressures of 0.2, 1.0, 2.0, and 3.5 ATA. | A chamber's pressure rating alone does not state the inspired oxygen partial pressure without knowing the breathing gas. |
| Pressure & physiology | Blood gas analyses in hyperbaric and underwater environments: a systematic review | 2022 | systematic review | Not stated | Not stated | This systematic review included 30 human arterial blood-gas studies, 25 of which collected data in hyperbaric chambers. | Buyers should compare documented pressure and breathing-gas conditions because blood-gas evidence spans different mixtures and exposure settings. |
| Pressure & physiology | Hyperbaric oxygenation therapy, basic concepts | 2000 | review | >=1.4 ATA | Not stated | The review describes Henry's, Dalton's, and Boyle's laws as relevant to a pressurized environment with high oxygen tension and defines its discussed configuration as at least 1.4 ATA with 100% oxygen. | Marketing that uses the term hyperbaric without stating both ATA and oxygen source leaves out two material equipment specifications. |
| Study pressure | Heart rate variability in healthy volunteers during normobaric and hyperbaric hyperoxia | 1999 | cohort | 2.5 ATA | 10 | Ten healthy volunteers underwent four conditions including 100% oxygen at 2.5 ATA, 21% oxygen at 2.5 ATA, 100% oxygen at 1 ATA, and air at 1 ATA. | This study separated pressure from oxygen fraction, so it cannot be represented as evidence for a low-pressure air-filled chamber without matching the exposure conditions. |
| Study pressure | Serum erythropoietin levels in healthy humans after a short period of normobaric and hyperbaric oxygen breathing: the normobaric oxygen paradox | 2006 | cohort | 2.5 ATA | 16 | Sixteen healthy volunteers received 100% oxygen at 2.5 ATA for 90 minutes, compared with a separate 100% oxygen at 1 ATA exposure for two hours. | The protocol's 2.5 ATA and 100% oxygen conditions are materially different from a 1.3-1.5 ATA chamber using a concentrator. |
| Study pressure | Beneficial effects of mild hyperbaric oxygen exposure on microcirculation in peripheral tissues in healthy subjects: a pilot study | 2022 | cohort | 1.4 ATA | 15 | This pilot study exposed 15 healthy people to 1.4 ATA with 35-39.5% oxygen for 70 minutes and compared it with 1 ATA, 20.9% oxygen. | It is a direct example of a mild-pressure protocol and should not be conflated with 2.0-2.5 ATA, 100% oxygen protocols. |
| Study pressure | B-type natriuretic peptide in healthy subjects after exposure to hyperbaric oxygen at 2.5 ATA | 2007 | cohort | 2.5 ATA | 8 | Eight healthy volunteers were compressed to 2.5 ATA and completed two 45-minute 100% oxygen periods separated by five minutes breathing air. | A published 2.5 ATA protocol includes both higher pressure and scheduled air breaks, which are distinct from a consumer chamber's basic pressure specification. |
| Study pressure | Antioxidant status in humans after exposure to hyperbaric oxygen | 1999 | cohort | 2.5 ATA | Not stated | The human-exposure study used 100% oxygen at 2.5 ATA in three 20-minute periods. | The published exposure combined 2.5 ATA, 100% oxygen, and an intermittent schedule rather than mild-pressure ambient air. |
| Study pressure | Transcranial cerebral oximetry in the hyperbaric environment | 1997 | cohort | 1.95-2.5 ATA | 7 | Seven healthy volunteers were monitored during hyperbaric oxygenation at 1.95 ATA and 2.5 ATA. | This protocol used pressures above the common 1.3-1.5 ATA flexible-chamber range, so its measurements should retain their stated exposure range. |
| Study pressure | Extension of pulmonary O2 tolerance in man at 2 ATA by intermittent O2 exposure | 1977 | cohort | 2.0 ATA | 5 | Five healthy volunteers breathed oxygen at 2 ATA in alternating 20-minute oxygen and five-minute normoxic-gas intervals. | The source documents a 2.0 ATA protocol with planned gas changes, demonstrating that treatment pressure and oxygen-delivery schedule are both part of a protocol. |
| Study pressure | Hyperbaric Oxygen Exposure Attenuates Circulating Stress Biomarkers: A Pilot Interventional Study | 2020 | cohort | 2.0-2.8 ATA | 10 | Ten healthy male volunteers completed a single program consisting of 2.8 ATA for 45 minutes followed by 2.0 ATA for 55 minutes. | The protocol used pressures at or above 2.0 ATA rather than a 1.3 ATA consumer-chamber exposure. |
| Study pressure | Oxidative Stress Response Kinetics after 60 Minutes at Different (1.4 ATA and 2.5 ATA) Hyperbaric Hyperoxia Exposures | 2023 | cohort | 1.4; 2.5 ATA | 14 | Fourteen healthy non-smokers completed one-hour pure-oxygen exposures at both 1.4 ATA and 2.5 ATA. | This head-to-head design makes the pressure distinction explicit and does not justify treating 1.4 ATA and 2.5 ATA hardware as interchangeable. |
| Oxygen delivery | Measurement of oxygen concentration in delivery systems used for hyperbaric oxygen therapy | 1996 | cohort | Not stated | Not stated | The comparative study found that an acceptable inspired oxygen fraction was reliably achieved with a continuously ventilated hood or with trained supervision of a demand-valve oral-nasal mask system. | A chamber quote should specify the actual patient interface and delivery system, not only the presence of an oxygen source. |
| Oxygen delivery | Efficient oxygen mask for patients undergoing hyperbaric oxygen therapy | 1977 | cohort | 2.4 ATA | 17 | At sea level and 2.4 ATA, properly fitted masks produced 96-99% end-inspired oxygen while improperly fitted masks ranged from 64% to 100%. | Mask fit and delivery hardware can change inspired oxygen substantially even when the same chamber pressure is used. |
| Oxygen delivery | Operational use and patient monitoring in a multiplace hyperbaric chamber | 1999 | review | Not stated | Not stated | This review states that multiplace-chamber operation requires managing chamber atmosphere and the partial pressures of component gases while minimizing fire hazards. | A chamber's occupant format affects how oxygen, monitoring, and safety systems are configured. |
| Oxygen delivery | Operational use and patient care in the monoplace hyperbaric chamber | 1999 | review | Not stated | Not stated | The review describes monoplace-chamber oxygen delivery and notes that air breaks can be provided, including for intubated or mechanically ventilated users. | Monoplace and multiplace configurations should not be compared as if they use the same oxygen-delivery workflow. |
| Oxygen delivery | Flexible oxygen concentrators for medical applications | 2021 | reference text | Not stated | Not stated | This engineering study states that medical-grade concentrator output is 90-96% oxygen by volume and that typical adsorption concentrators produce about 90-93% oxygen at less than 10 L/min. | A concentrator specification describes oxygen-enriched output rather than a 100% oxygen source, so purity and flow should be listed separately. |
| Safety & engineering | Follow Instructions for Safe Use of Hyperbaric Oxygen Therapy Devices | 2025 | standards document | Not stated | Not stated | The FDA states that high oxygen concentrations heighten fire risk and directs users and facilities to follow manufacturer instructions, grounding, maintenance, safety checks, and prohibited-item controls. | Safety documentation, maintenance requirements, grounding, and the vendor's operating instructions are purchase criteria rather than optional accessories. |
| Safety & engineering | Fire protection for hyperbaric facilities in hospitals | 2021 | standards document | 3.0 ATA | Not stated | The NFPA article identifies Chapter 14 of NFPA 99 as the hyperbaric-facility requirements source and describes fire-protection provisions for chamber and room configurations. | For a facility installation, request the specific NFPA 99 applicability analysis and installed fire-protection design rather than relying on a generic safety claim. |
| Safety & engineering | Technical ensurement of fire-proof in hyperbaric oxyger chambers | 1999 | reference text | Not stated | Not stated | The article addresses fire-prevention material selection, causes of burning, and technical fire-prevention measures in hyperbaric oxygen chambers. | Chamber safety evaluation should include material controls and ignition prevention, not only the pressure-vessel rating. |
| Safety & engineering | Ignition by electrostatic sparks in hyperbaric oxygen | 1966 | reference text | Not stated | Not stated | This article identifies electrostatic sparks as an ignition issue in a hyperbaric oxygen environment. | Ask how the installation controls static, grounding, clothing, and electronics before operating in an oxygen-enriched environment. |
| Safety & engineering | The selection of skin care products for use in hyperbaric chamber may depend on flammability acceptability indices score | 2008 | reference text | Not stated | Not stated | The materials study reports that elevated oxygen fraction and pressure increase flammability potential and that all tested products ignited in 99.5% oxygen under pressure. | The vendor's allowed-items and materials list matters because material behavior changes in an oxygen-enriched pressurized environment. |
| Safety & engineering | Hyperbaric Oxygen Therapy and Oxygen Compatibility of Skin and Wound Care Products | 2017 | reference text | 3.0 ATA | Not stated | Testing of materials at 60 degrees Celsius and 3 atmospheres of pressurized oxygen found no self-ignition among 44 articles in the oxygen-exposure method and noted no test standard specific to these conditions. | Do not infer oxygen compatibility from ordinary consumer use; ask what testing or controls support the chamber's permitted materials list. |
| Safety & engineering | Check-up of the hyperbaric chamber and attached equipment | 1998 | reference text | Not stated | Not stated | The article proposes checks for the pressure vessel, electrical systems, instruments, mechanical equipment, piping, air-conditioning, hygiene testing, and operating rules after chamber construction or repair. | A used or newly installed chamber should come with documented inspection and service history for more than the shell alone. |
| Safety & engineering | Technology of hyperbaric chambers | 1999 | review | Not stated | Not stated | The review identifies medical gas supplies, chamber hulls, controls, alarm and monitoring systems, fire-fighting equipment, deluge systems, and pressure locks as technical hyperbaric-chamber requirements. | Compare the safety systems and support infrastructure included with a system rather than comparing vessel pressure alone. |
| Safety & engineering | Identification and control of a multiplace hyperbaric chamber | 2018 | reference text | Not stated | Not stated | This chamber-control study reports pressure-profile tracking and repeatability with Pause and Alleviation procedures in an automated multiplace system. | For a commercial system, evaluate controls, logging, alarms, and repeatable compression and decompression profiles. |
| Barotrauma | Middle ear barotrauma associated with hyperbaric oxygenation treatment | 1993 | cohort | Not stated | 67 | In 67 users receiving hyperbaric oxygenation, objective otoscopic grading found middle-ear barotrauma in 68.7%. | A buyer intending unsupervised home use should consider whether every intended user can equalize pressure and follow the manufacturer's response procedure for ear discomfort. |
| Barotrauma | Middle-ear barotrauma after hyperbaric oxygen therapy: a five-year retrospective analysis on 2,610 patients | 2020 | cohort | Not stated | 2,610 | This five-year retrospective study reported middle-ear barotrauma in 262 of 2,610 users and stated that it caused some premature discontinuations. | Home-operation plans should account for the ability to stop or modify a session if equalization is not possible. |
| Barotrauma | Middle ear barotrauma in hyperbaric oxygen therapy | 2014 | cohort | Not stated | 236 | In a retrospective review of 236 users and 4,981 treatments, the reported middle-ear barotrauma incidence was 43.2%, with most cases having lower TEED scores of 1 or 2. | Compression-rate controls and user training are decision points because pressure equalization is part of every session. |
| Barotrauma | Middle ear barotrauma during hyperbaric oxygen therapy; a review of occurrences in 5,962 patients | 2019 | cohort | Not stated | 5,962 | This retrospective review recorded 549 middle-ear barotraumas over eight years and reported suspension of therapy for 89 users. | The chamber's control, communication, and decompression procedures should permit a user or attendant to respond promptly to equalization difficulty. |
| Barotrauma | Update on Middle Ear Barotrauma after Hyperbaric Oxygen Therapy—Insights on Pathophysiology | 2014 | review | 2.0 ATA | Not stated | The review states that middle-ear barotrauma occurs especially during compression and that most cases occur during the first 10 meters of compression, described as equivalent to 2 ATA. | A home buyer should not assume that an ear or sinus issue can be safely managed without screening, equalization ability, and a clear stop procedure. |
| Barotrauma | Middle ear barotrauma with hyperbaric oxygen therapy: incidence and the predictive value of the nine-step inflation/deflation test and otoscopy | 2008 | cohort | Not stated | 18 | In a prospective study of 18 adults, middle-ear barotrauma occurred in 12 users after seven days of hyperbaric oxygen therapy. | User screening and a plan for problems with middle-ear inflation are relevant before buying a chamber intended for repeated home sessions. |
| Barotrauma | Inner and middle ear hyperbaric oxygen-induced barotrauma | 1997 | cohort | Not stated | 30 | This study found middle-ear barotrauma in 10 of 11 users unable to autoinflate the middle ear and in 7 of 19 able to autoinflate. | Ability to equalize ear pressure is a practical gate for unsupervised use and should be addressed before purchase rather than after installation. |
| Room environment | The evaluation of in-chamber sound levels during hyperbaric oxygen applications: Results of 41 centres | 2020 | cohort | 2.4 ATA | 41 | At 2.4 ATA in 41 centers, the highest measured equivalent continuous sound level was 100.4 dB(A) with ventilation and the lowest was 40.5 dB(A) without ventilation. | Noise specifications and the way ventilation operates can affect comfort and should be discussed with the vendor for the planned room. |
| Room environment | Noise: a hazard to divers and hyperbaric chamber personnel | 1971 | reference text | Not stated | Not stated | This journal article identifies noise as a hazard for divers and hyperbaric chamber personnel. | Noise is an equipment and room-planning consideration that should be checked with the chamber running, not only from a brochure value. |
| Room environment | Effectiveness of hyperbaric chamber ventilation | 2023 | reference text | 1.6-2.8 ATA | Not stated | Measurements in a clinical chamber at 160, 220, and 280 kPa found local underventilation at some sampling points and stated that oxygen accumulation in such zones can increase chamber-fire risk. | Ventilation design, compressor exhaust, and cooling should be treated as installation requirements, especially where oxygen may enter the chamber atmosphere. |
| Room environment | Design and Human Factors of Therapeutic Hyperbaric Chambers | 2016 | review | Not stated | Not stated | This review frames therapeutic-chamber design around the person, environment, and machine, including personal space, privacy, hazard mitigation, seating, and user-tailored features. | Footprint, entry posture, visibility, seating, communication, and room circulation are buying criteria alongside maximum ATA. |
| Shell limits | UHMS announces position statement on low-pressure, soft-sided hyperbaric chambers | 2017 | standards document | Not stated | Not stated | This UHMS publication announces a position statement specifically addressing low-pressure, soft-sided hyperbaric chambers. | Soft-sided construction should be compared within its documented low-pressure category rather than against rigid systems by name alone. |
| Shell limits | UHMS Position Statement in full: low-pressure fabric hyperbaric chambers | 2018 | standards document | Not stated | Not stated | This UHMS position statement is specifically about low-pressure fabric hyperbaric chambers, and the PubMed record provides no operating-pressure value in its abstract record. | A buyer should ask the manufacturer for the vessel's documented maximum operating pressure, test history, and relief-valve information rather than infer capacity from fabric construction alone. |
02
What this evidence does not establish
| # | Not established |
|---|---|
| 01 | That a 1.3–1.5 ATA chamber delivers the exposure used in the 2.0–2.8 ATA, 100% oxygen protocols cited below. |
| 02 | That an oxygen concentrator is equivalent to a 100% oxygen supply. Published concentrator output is 90–96% by volume. |
| 03 | That a flow rating answers the separate questions of purity at that flow, outlet pressure, interface and fit. |
| 04 | That a lower pressure makes a chamber inherently fire-safe. FDA's August 2025 letter describes a heightened fire risk with high oxygen concentration and does not carve out low-pressure devices. |
| 05 | That ear and sinus equalisation can be assumed manageable in unsupervised use. Reported middle-ear barotrauma incidence in the series below ranges from roughly 10% to 68.7%. |
| 06 | That fabric construction tells you a chamber's operating pressure. Ask for the documented maximum operating pressure, test history and relief-valve information. |
| 07 | Any therapeutic claim whatsoever. Nothing in this table is a statement that a chamber treats a condition. |
Regulatory context: FDA Letter to Health Care Providers, 25 Aug 2025 · FDA consumer update 'Hyperbaric Oxygen Therapy: Get the Facts' (content current as of 07/26/2021; live URL now 404, archived capture) · FDA Product Classification — chamber, hyperbaric (CBF) · Flexible oxygen concentrators for medical applications (2021) · UHMS position statement — low-pressure fabric hyperbaric chambers (2018). FDA's consumer page carrying its list of cleared indications now returns Page Not Found at its original URL; the archived capture is dated “content current as of 07/26/2021” and is cited as such.