If you are buying a chamber for a business, the purchase decision is not really about the chamber. It is about which revenue model the equipment can serve, and those models have very different rules. Medicare's rules in particular constrain who may bill, in what setting, for what indication — and a chamber bought without reading them can be a chamber that cannot be billed for at all. This page sets out the published structure. It does not model your revenue, because doing that from a web page would require inventing your volumes.
The two codes, and what they actually say
Medicare's Claims Processing Manual, Chapter 32, describes the facility code as G0277, "Hyperbaric oxygen under pressure, full body chamber, per 30-minute interval," and states plainly: "Code G0277 is not available for use other than in a hospital outpatient department." Physician work is billed separately under CPT 99183 for attendance and supervision of hyperbaric oxygen therapy, per session (CMS Medicare Claims Processing Manual, Chapter 32).
Read that setting restriction carefully, because it does most of the work in this market. A wellness studio, a chiropractic office, a private clinic that is not a hospital outpatient department — none of those are the setting G0277 contemplates. Buying a clinical monoplace chamber on the assumption that G0277 revenue follows is the single most expensive planning error we see, and it is discoverable in one sentence of a public CMS manual before anyone signs anything.
We could not verify the current CY2026 OPPS payment amount for G0277 from a primary CMS source within the scope of this build, so no dollar figure for it appears on this page. UHMS's regulatory affairs page states that "the OPPS APC code 0659 / G0277 will be paid at about $109.24 for a 30 minute segment," but that statement is undated on the page and we are not treating it as a current rate (UHMS regulatory affairs). The authoritative figure is in CMS's quarterly OPPS Addendum B for the current quarter (CMS Quarterly Addenda Updates). Look it up there, or have your billing staff do it, and put the date of the lookup in your model.
Coverage is by indication, through a national determination
Payment does not follow from owning a chamber; it follows from a covered indication being treated and documented. Medicare coverage of hyperbaric oxygen therapy is governed by National Coverage Determination 20.29, referenced from the same claims processing chapter (CMS Claims Processing Manual, Chapter 32). The covered indication list under that determination is narrower than the range of conditions people commonly ask clinics about, and it is narrower again than the marketing that circulates around home chambers.
The FDA-cleared marketing list is a separate list from the Medicare coverage list, and neither is the same as the set of conditions a professional society considers supported. Confusing the three is routine. See what clearance actually means for the FDA list, quoted with its date and its archival status.
Private pay changes the equipment question completely
A private-pay wellness model is not bound by G0277's hospital-outpatient restriction, because it is not billing G0277. That freedom comes with two constraints that bear directly on equipment choice.
First, hyperbaric chambers are prescription devices. FDA states it directly: "Hyperbaric oxygen chambers are prescription devices, and we have received numerous complaints … regarding their use in facilities not operated by a licensed physician" (FDA CDRH letter to state medical boards, 22 August 2013), and the general prescription-device rule at 21 CFR 801.109 makes the labelling exemption conditional on sale "only to or on the prescription or other order of such practitioner" (GPO text of 21 CFR 801.109). A business model that assumes walk-in retail sessions with no practitioner involvement is a model built on top of a prescription device.
Second, what you may say in marketing is limited by what is cleared and what is established. FDA has specifically noted awareness of "hyperbaric oxygen treatment centers promoting hyperbaric oxygen chambers for uses that have not been cleared or approved by the FDA, such as treatment of cancer, Lyme disease, autism, or Alzheimer's disease" (FDA bulletin, 26 July 2021). A private-pay model whose demand depends on those claims is a compliance exposure, not a revenue plan.
What the facility requirements do to the capital plan
A commercial installation is a construction project as much as an equipment purchase. Under NFPA 99 Chapter 14, chambers are classified as Class A (human, multiple occupancy), Class B (human, single occupancy) or Class C (animal, no human occupancy). For a Class A chamber inside a building, "the chamber(s) and all ancillary service equipment shall be protected by 2-hour fire-resistant-rated construction," while Class B and C chambers inside a building are not required to have that rating. The room housing a Class A or Class B chamber "shall be for the exclusive use of the hyperbaric operation." Sprinklers to NFPA 13 or water mist to NFPA 750 "shall be installed in the room housing a Class A, Class B, or Class C chamber and in any ancillary equipment rooms." And the foundation "shall be designed to support the chamber and all associated equipment" (NFPA 99, 2015 edition, clauses 14.1.2.2, 14.2.1.1, 14.2.1.1.2, 14.2.1.1.7, 14.2.1.1.9, 14.2.1.2). The edition your authority having jurisdiction enforces is the one that governs.
Two derived consequences worth putting in a pro forma. A single-occupancy Class B chamber avoids the two-hour construction requirement that a multi-person Class A chamber triggers, which is a material difference in fit-out cost — so the choice between a one-person and a two-person chamber is partly a construction decision. And an exclusive-use room means the square footage cannot double as storage or as a second treatment space, which changes revenue per square foot, not just cost.
Standby power is a further line: UHMS advises 24 hours of generator fuel, and 96 hours in areas prone to extended outages (UHMS standards and codes FAQ).
Staffing is not optional in the way buyers hope
UHMS recommends "that physicians or, as permitted by local regulations, supervised non-physician providers who are appropriately trained in Undersea and Hyperbaric Medicine, be available immediately throughout the administration of hyperbaric oxygen therapy" (UHMS Position Statement, revised 10 July 2018). FDA's 2025 letter recommends ensuring staff training is maintained and that "the patient is properly monitored and supervised for the duration of the treatment" (FDA Letter to Health Care Providers, 25 August 2025).
In business terms: sessions are attended, so labour scales with utilisation rather than sitting fixed, and a chamber running eight sessions a day is eight sessions of a trained person's time. Under CPT 99183 the physician attendance is separately billable in the settings where billing applies, which tells you the payer treats it as work rather than as overhead (CMS Claims Processing Manual, Chapter 32).
Throughput arithmetic you can do without inventing numbers
Some capacity limits are engineering facts. G0277 is defined per 30-minute interval, which tells you the billing granularity of a session but not its length. Session length in the published clinical literature is typically structured in blocks with air breaks — one protocol used two 45-minute oxygen periods separated by five minutes of air (PMID 17225483), another used three 20-minute periods (PMID 10517981). Compression and decompression add time on top: the Sechrist H-series specifies an emergency vent from 30 psig to 0 in a maximum of 119 seconds, which is an emergency rate and not a normal decompression schedule (Sechrist H-series specifications).
So daily capacity is a function of session protocol, compression and decompression time, turnaround and cleaning, and staffing hours. We are not going to publish a sessions-per-day figure, because it depends on all four and any single number would be marketing. Build it from your own protocol and the manufacturer's compression rates.
The question to answer before you buy
Not "what does the chamber cost" but "which of these three models am I actually in?" A hospital outpatient department can bill G0277 for covered indications under NCD 20.29. A private-pay wellness business cannot, and must build a model that survives without it while respecting prescription-device status and claim limits. A multi-person clinical installation adds NFPA 99 Class A construction to the capital plan. Those are three different businesses with three different chambers, and the equipment decision follows from the model rather than the other way round.
We install and service chambers and sell equipment, so we benefit when a chamber gets bought. That is exactly why this page tells you where the revenue does not exist: a clinic that buys the wrong chamber for its model becomes a service problem, a refund conversation, and a reference we cannot use.
Sources on this page
- CMS Medicare Claims Processing Manual, Chapter 32 (G0277, 99183, NCD 20.29 reference) — cms.gov PDF
- CMS OPPS Quarterly Addenda Updates (authoritative current payment amounts) — cms.gov
- UHMS regulatory affairs page (undated APC 0659 statement) — uhms.org
- NFPA 99 (2015 ed.) Chapter 14 — PDF
- UHMS Position Statement, Low-Pressure Fabric Hyperbaric Chambers — uhms.org
- UHMS standards and codes FAQ — uhms.org
- FDA Letter to Health Care Providers, 25 Aug 2025 — fda.gov
- FDA CDRH letter to state medical boards, 22 Aug 2013 — dhp.virginia.gov
- 21 CFR 801.109 — govinfo.gov
- Sechrist H-series specifications — brochure PDF