The monoplace versus multiplace question splits along practical lines. Hospitals running emergency CO or decompression cases lean multiplace. Outpatient wound clinics lean monoplace.
Both deliver hospital-grade HBOT inside the 14 UHMS-approved indications. The choice depends on the clinical setting.
This guide walks through the practical differences. Cost, throughput, patient experience, emergency capability, and where each type fits in the US care landscape. The goal is to help patients and clinic operators understand why a facility chose one over the other — and what that choice means for the care they deliver.
What each chamber is
Monoplace chambers are single-patient acrylic or steel cylinders. Patients lie down inside while the chamber pressurizes with 100% oxygen.
Treatment runs 90 to 120 minutes at 2.0 to 2.4 ATA. Staff observe through the clear shell and talk via intercom.
Multiplace chambers are larger steel vessels that hold 4 to 14 patients plus medical staff. The chamber pressurizes with compressed air, and patients breathe 100% oxygen through hoods or masks.
Inside techs and physicians can adjust care, manage emergencies, and treat critically ill patients during the dive.
The hardware tradeoff is clear. Monoplace chambers are smaller, cheaper, and easier to operate. Multiplace chambers are more expensive, require larger facilities, and enable hands-on care during treatment.
Manufacturer landscape
The market splits along chamber type.
Monoplace builders dominate the outpatient wound care sector. Sechrist Industries holds the largest US share with the 3300H and 2500B series, both 510(k)-cleared per the FDA database.
Perry Baromedical builds the Sigma series used in many hospital wound centers. ETC Biomedical and Healing Chambers International round out the US builder list.
Multiplace builders include Perry Baromedical, ETC Biomedical, and Reimers Engineering. These systems are more custom.
Most are built to site specs. Hatch size, patient count, and emergency features are set per site.
OxyHealth, Newtowne Hyperbarics, and Summit to Sea build only soft-shell chambers at 1.3 ATA. These are not in the same regulatory class as monoplace or multiplace hospital systems. Class A monoplace and multiplace hardware is sold only to medical facilities.
Aviv Clinics in Florida runs Perry Baromedical multiplace chambers for its Efrati protocol. Restore Hyper Wellness uses monoplace and soft-shell mild chambers across its franchise sites. See Aviv Clinics evidence vs. marketing for the marketing-vs-evidence breakdown.
Cost comparison
| Cost dimension | Monoplace | Multiplace |
|---|---|---|
| Chamber capital cost | $100K–$250K | $1M–$5M+ |
| Facility build-out | $50K–$150K | $500K–$2M |
| Annual operating cost | $30K–$80K | $200K–$500K |
| Staffing per shift | 1 tech | 2 techs + RN + physician on call |
| Per-session reimbursement (G0277) | ~$109–$250 | ~$109–$250 |
| Cost per treated patient | $90–$180 | $250–$600 |
Insurance pays the same under CMS HCPCS code G0277 for both chamber types. A monoplace and a multiplace clinic billing for the same FDA-approved use get the same per-session payment.
The economic reality: multiplace chambers need patient volume to cover their high capital and staffing costs. Monoplace chambers can break even with smaller panels.
This is why monoplace systems dominate US outpatient wound care.
Throughput and scheduling
Monoplace throughput scales linearly with chamber count. A clinic with four monoplace chambers can run roughly 20 to 32 patient sessions per day depending on shift length and turnover time. Each chamber operates independently, so scheduling is flexible and a single late patient does not delay others.
Multiplace throughput is higher per chamber. A single 8-patient multiplace chamber can deliver 16 to 24 sessions per day.
But all patients in a given dive run on the same schedule. A late or no-show patient affects the whole chamber.
For outpatient wound care with steady scheduling, monoplace flexibility wins. For high-volume emergency care or military dive work, multiplace economics win.
Patient experience
The lying-down experience differs meaningfully.
Monoplace patients lie flat inside the acrylic shell. The chamber is clear and well-lit, but solo.
Many patients watch movies or listen to audio through the chamber's media system. Claustrophobia is harder to manage because the patient is alone.
Multiplace patients sit or recline inside a larger room-like space with other patients and staff. The setting feels less confining for claustrophobic patients. In-chamber techs can talk with patients, check ear equalization, and address discomfort in real time.
For kids and adults with bad claustrophobia, multiplace is the better pick. For adults who do fine in tight spaces, monoplace works.
Emergency capability
This is where multiplace shows its clinical strength.
In a multiplace chamber, a physician or RN can enter mid-dive to provide care. They can place IVs, adjust vent settings, manage seizures, and respond to cardiac events without ending the dive.
This matters most for unstable patients. CO poisoning cases, decompression sickness emergencies, and ICU-level patients all benefit.
In a monoplace chamber, any in-chamber emergency requires decompression to bring staff in. Decompression takes 10 to 20 minutes minimum. For an unstable patient, that delay can be clinically significant.
Hospitals running emergency HBOT need multiplace. Outpatient wound clinics with stable patients and routine cases do not.
Where each type is used in the US
Monoplace dominates outpatient wound care. Most of the 1,588 HBOT centers tracked in the US operate monoplace chambers. Wound care for diabetic ulcers, radiation tissue damage, and chronic non-healing wounds is the bulk of US HBOT volume, and monoplace fits this care model.
Multiplace dominates hospital emergency care. Major academic centers, military dive sites, and big referral hospitals run them. Examples include Penn, Duke, and LSU.
These sites handle CO cases, dive injuries, and ICU patients.
Mixed-mode facilities are growing. Some larger HBOT centers operate both monoplace and multiplace chambers to cover routine outpatient care and emergency referrals in the same facility.
Pressure equivalence
Both chamber types deliver 2.0 to 3.0 ATA. The clinical evidence that anchors the 14 UHMS indications was developed across both formats.
The 2015 Cochrane review on diabetic wounds included trials at both chamber types. Outcomes did not differ much by chamber format.
The 2018 Eskes review on osteomyelitis drew from both formats too. See the osteomyelitis evidence atlas for the full study-by-study evidence breakdown.
For the FDA-approved uses, chamber type does not drive outcomes. What matters is pressure, session count, and patient selection.
Both formats deliver the protocols that built the approved list.
UHMS accreditation
Roughly 180 of the 1,588 HBOT centers tracked in the US carry UHMS accreditation — about 11%. Accreditation applies to both monoplace and multiplace facilities. The requirements are the same:
- Medical director trained in hyperbaric medicine
- CHT or CHRN-certified technicians
- Documented emergency and fire protocols
- Annual chamber inspections by qualified third parties
When picking an HBOT center, ask about UHMS status before chamber type. An accredited monoplace site is a safer bet than a non-accredited multiplace one.
Safety profile
Risk profiles are similar across both chamber types. Middle ear barotrauma is the most common adverse event in both, with rates of 2% to 10% per the Camporesi 2014 review in Undersea & Hyperbaric Medicine. Central nervous system oxygen toxicity seizures occur at roughly 1 to 4 per 10,000 sessions at 2.4 ATA across both formats.
Fire risk is the most serious shared concern. The 1997 Milan chamber fire — which killed 11 people — happened in a multiplace chamber. Multiplace fires can affect multiple patients simultaneously and remain a sober reminder of why fire safety protocols matter.
Both chamber types must meet NFPA 99 standards. The rules cover build, fire safety, and emergency systems.
Trained staff follow strict rules:
- No synthetic clothes
- No electronics
- Pre-breathing on pure O2
- Exhaust scrubbing on each cycle
Which type to look for as a patient
The chamber type to look for depends on your condition and clinical situation.
Stable outpatient with chronic wound or radiation injury: A monoplace at an accredited wound care center is the right fit. The care is steady, the chamber type does not change the outcome, and cost is lower per session.
Critically ill or unstable patient: A multiplace chamber is the right pick. Staff can manage you during the dive. This usually means a hospital HBOT program, not an outpatient clinic.
Child with claustrophobia: A multiplace chamber is kinder. The patient is not alone, and a parent or nurse can sometimes ride along.
Emergency CO poisoning or decompression sickness: Always a hospital with multiplace and 24/7 staff. These cases are not safe at outpatient monoplace sites.
Related reading
- Hospital vs private HBOT centers: pros and cons
- UHMS facility accreditation: what it signals to patients
- Hard chamber vs soft chamber HBOT: real clinical differences
- HBOT cost in 2026: insurance, out-of-pocket, home chambers
Frequently asked questions
Is one chamber type safer than the other?
Both have comparable safety profiles when operated by trained staff. Multiplace chambers allow in-chamber emergency response, which is an advantage for unstable patients. Monoplace chambers have a smaller risk surface per session because there's only one patient. Overall risk depends more on operator training and UHMS accreditation than on chamber type.
Does insurance pay the same for both?
Yes. Medicare HCPCS code G0277 reimburses per session regardless of chamber type. Private insurers generally follow the same per-session model. The difference is in clinic economics, not patient cost.
Can I bring a family member into a multiplace chamber with me?
Sometimes. Some pediatric and special-needs cases allow a parent or caregiver to accompany the patient. This requires the chamber operator's approval, pre-dive screening of the accompanying person, and an additional fee in many cases. Not all multiplace facilities permit this.
Which type does Aviv Clinics use?
Aviv Clinics operates Perry Baromedical multiplace systems for the Efrati protocol packages. The multiplace format supports the group treatment model and the in-chamber staffing required for Aviv's care approach. Aviv's anti-aging and cognitive protocols are off-label uses — the Hachmo 2020 telomere study at Tel Aviv University used a similar multiplace setup but remains a single 35-patient trial without independent replication.
Are home hyperbaric chambers monoplace or multiplace?
Neither in the medical sense. Home chambers are soft-shell consumer devices cleared by the FDA only for acute mountain sickness at 1.3 ATA. They are not equivalent to hospital monoplace or multiplace chambers, which operate at 2.0 to 3.0 ATA under Class A medical clearance. The pressure gap is more than tenfold in arterial oxygen tension per Tibbles & Edelsberg 1996 in NEJM.
Medical disclaimer
This article is for informational purposes only and is not a substitute for professional medical advice. Hyperbaric oxygen therapy is investigational for most off-label uses discussed here. Consult your doctor before starting any HBOT protocol, especially if you have pre-existing ear, lung, or cardiovascular conditions. Verify a clinic's UHMS accreditation, medical director credentials, and FDA-cleared scope of practice before booking.
-- The HBOT Finder Team