Key takeaways
- Two fatal hyperbaric chamber fires occurred in 2025: a 5-year-old at the Oxford Center in Troy, Michigan (January 2025) and an adult in a Fortius 420 soft-shell chamber in Arizona (July 2025).
- Static electricity from a bare mattress ignited the Michigan fire; electronics (tablet, phone, fan) found in the chamber were implicated in the Arizona case.
- The FDA issued a Letter to Health Care Providers on 25 August 2025 reinforcing adherence to manufacturer Instructions for Use, static control, cotton-only clothing, and electronics exclusion.
- All major safety guidance (FDA, UHMS, NFPA 99 Chapter 14) is consistent: no electronics in-chamber, no petroleum products, 100% cotton clothing, trained operator.
- Both incidents involved facilities operating off-label. UHMS-accredited clinical facilities have an exceptional long-term fire safety record when protocols are followed.
What happened in 2025
Two separate fatal hyperbaric chamber fires occurred in the United States in 2025, bringing an unusually sharp spotlight to HBOT safety. The first was on 31 January 2025 at the Oxford Center in Troy, Michigan, where 5-year-old Thomas Cooper died when the chamber he was being treated in ignited during a session. Forensic investigation traced the ignition to a single electrostatic discharge from the child's knee contacting a bare mattress inside the chamber.
The second occurred on 9 July 2025 inside a Fortius 420 soft-shell chamber manufactured by OxyHealth, in Arizona. Investigators recovered a melted electronic tablet, a cell phone, and a fan from inside the chamber — clear indications that battery-powered electronics were present during treatment, in direct violation of manufacturer and NFPA 99 guidance.
The FDA response
On 25 August 2025, the FDA issued a Letter to Health Care Providers reinforcing the critical importance of following manufacturer Instructions for Use for every HBOT device. The letter does not change device clearances or introduce new standards; it is a reminder that existing standards exist for a reason and that the two 2025 fatalities would have been preventable under full protocol compliance.
The FDA's recommendations align with long-standing UHMS and NFPA 99 Chapter 14 guidance:
- No personal electronics in-chamber — no phones, tablets, battery-powered toys, hearing aids with batteries, insulin pumps, or electric blankets.
- 100% cotton clothing only — synthetic fabrics in an oxygen-enriched atmosphere dramatically accelerate combustion.
- No petroleum-based products — no lotions, hair products, deodorants (unless HBOT-rated), perfumes, nail polish, or lip balm on treatment day.
- Static control — grounded flooring, cotton bedding or dedicated HBOT mattress covers, and verified humidity levels.
- Trained operator present — continuous supervision throughout compression, treatment, and decompression.
Why oxygen fires are different
An oxygen-enriched environment at elevated pressure is not simply "more flammable" — it is categorically more dangerous. Materials that would merely scorch in room air burn vigorously in 100% oxygen, and burn even more vigorously under pressure. A small spark that would self-extinguish in normal atmosphere can trigger a flash fire inside a chamber. This is why every element of chamber operation — fabric, electronics, cosmetics, flooring — is tightly controlled.
The clinical vs home-use split
It is important to separate the risk profile of clinical UHMS-accredited HBOT from home-use soft-shell operation. UHMS-accredited US facilities have a decades-long safety record approaching zero fire fatalities. The 2025 cases both involved facilities operating off-label, with weaker operator training and informal protocol compliance.
Soft-shell 1.3 ATA chambers are FDA-cleared only for altitude sickness. The large off-label home market — wellness, longevity, autism, long COVID, TBI — operates outside the rigorous training environment of clinical hyperbaric medicine, and this is where the 2025 fatalities concentrated.
What patients should ask
For patients evaluating any HBOT provider — clinical or off-label — the practical questions are:
- Is the facility UHMS-accredited? (See our clinic directory and verify with UHMS directly.)
- Does the operator have CHT (Certified Hyperbaric Technologist) or equivalent credentialing?
- Are personal electronics strictly prohibited inside the chamber?
- Is cotton-only garment compliance verified before every session?
- Is fire detection and emergency depressurisation capability present and tested?
Bottom line
The 2025 fatalities were preventable protocol breaches, not inherent equipment failures. The FDA Letter is a reminder, not a redesign. Patients and operators who follow established UHMS and NFPA 99 safety standards continue to have an excellent safety record. Those who treat HBOT as a casual wellness product — bringing tablets into chambers, using bare mattresses, skipping cotton garment compliance — are the risk population that the FDA guidance is attempting to reach.
Frequently Asked Questions
How common are HBOT chamber fires?
Extremely rare. Prior to 2025 the modal US year had zero HBOT fire fatalities. The two 2025 deaths concentrated attention because both involved identifiable protocol breaches rather than equipment failure.
Are soft-shell chambers more dangerous?
Soft-shell chambers are not inherently more dangerous when operated correctly, but the off-label home-use market has weaker operator training, more informal protocols, and higher risk of electronics entering the chamber.
What does the FDA require now?
The 25 August 2025 FDA letter does not change device clearances. It reinforces existing manufacturer Instructions for Use — no personal electronics, cotton-only clothing, no petroleum-based skincare, trained operator present during every session.
What should patients ask a facility?
Verify UHMS accreditation (for medical HBOT), confirm the facility prohibits electronics in-chamber, has fire detection and suppression protocols, and that cotton garments are provided.
