Fire Safety in Hyperbaric Facilities: What NFPA 99 and the FDA Expect
Oxygen-rich chambers carry a real fire risk. NFPA 99 Chapter 14 and a 2025 FDA safety letter set out grounding, materials and training rules operators must follow.
Why fire is the central hazard
Every safety conversation about hyperbaric oxygen therapy comes back to one physical fact: oxygen itself does not burn, but it makes almost everything else burn faster and hotter. Inside a chamber enriched with oxygen, a spark that would be harmless in ordinary air can become a serious fire in seconds. This is why hyperbaric facilities are governed by detailed fire-safety rules rather than by general medical-equipment guidance.
What NFPA 99 Chapter 14 covers
In the United States, the central reference is NFPA 99, the Health Care Facilities Code, whose Chapter 14 is devoted to hyperbaric facilities. It sets expectations across construction, equipment and operations. Chambers are expected to be built to the ASME PVHO-1 pressure-vessel standard. Flammable gases are prohibited in the rooms that house a chamber, and unapproved electronic devices are not permitted inside a chamber even when it is pressurized with air rather than pure oxygen.
The code also addresses grounding, static control, permitted materials and clothing, and staff procedures. Editions matter here: the FDA has recognized the 2024 edition, while some payers and programs still reference older versions, so operators need to confirm which edition applies to their setting.
The 2025 FDA safety letter
In 2025 the issue moved from standards documents into a direct warning. On August 25, 2025, the FDA issued a Letter to Health Care Providers after reports of fires involving HBOT devices that led to serious injuries and deaths, noting that the root cause of these events was not established. The letter urged providers to follow each device's instructions for use, to enforce fire-prevention measures, to ensure proper grounding, to keep in mind the heightened fire risk of high-concentration oxygen, to train staff on an ongoing basis, and to keep patients in hyperbaric-compatible clothing under continuous monitoring.
What buyers and operators should verify
For anyone on the buying side, fire safety is not an optional extra but a core part of the purchase. Before comparing prices, it is worth understanding the standards a compliant installation must meet; our guide on how to buy a hyperbaric chamber (buying guide) is a reasonable place to begin mapping those requirements. Key questions include whether the chamber meets recognized construction standards, how grounding and static control are handled, which materials and garments are permitted inside, and what training the operating staff have completed.
Accreditation adds a further layer of assurance. Bodies such as the Undersea and Hyperbaric Medical Society run facility safety and accreditation programs, and a center's willingness to discuss its standards, training records and incident procedures is itself a useful signal. The same physics applies well beyond hospitals, so lower-cost and home installations are not exempt from the fire risk that these rules exist to control.
Fire safety in hyperbaric medicine is a shared responsibility of manufacturers, facilities and trained staff, and the standards exist because the risk is real. None of it replaces professional guidance: decisions about whether and where to undergo HBOT belong with a qualified physician and a properly accredited facility.