Author(s): Stephanie Schorow. Published on January 3, 2017.

The Air in There

Hyperbaric chambers have been touted for their healing and restorative powers, but a proliferation of the devices has experts concerned about the potential fire hazard


THE FAMILY OF Francesco Martinisi only wanted the best for their four-year-old son, born with cerebral palsy. His father brought him to the United States from Italy, hoping the boy would be helped by breathing pressurized oxygen in a hyperbaric chamber at a Florida clinic. His 62-year-old grandmother even came into the chamber to keep him company.

On May 1, 2009, the chamber erupted in fire, fed by the oxygen inside. Unable to get out, Francesco and his grandmother endured five minutes of flames that burned more than 90 percent of their bodies. Neither survived.

The incident and other serious accidents involving hyperbaric chambers have alarmed many in the life-safety community, including Tom Workman, director of quality assurance and regulatory affairs for the Undersea and Hyperbaric Medical Society. Workman, a member of the Hyperbaric and Hypobaric Facilities Committee of NFPA 99, Health Care Facilities Code, has been tracking the proliferation of hyperbaric chambers around the country. While he believes the vast majority of the chambers in hospitals or clinical health care facilities are operated safely and effectively, he sees ominous developments in the use of chambers in non-clinical settings and in private homes.

“It’s a big issue and it unfortunately keeps getting bigger and bigger,” said Workman, who hopes to alert fire marshals and other authorities to the spread of hyperbaric chambers that do not comply with NFPA code provisions.

Outside picture of the Florida clinic where a woman and her grandson died in a fire that occurred in a hyperbaric chamber in 2009.

The Florida Clinic where a woman and her grandson died in a fire that occurred in a hyperbaric chamber in 2009. Photograph: Newscom

Hyperbaric oxygen therapy (HBO2) involves breathing near 100 percent oxygen in an environment in which the atmospheric pressure is raised to three times higher than normal, in either a multi-person or a single-person chamber. Hyperbaric chambers are classified by the U.S. Food and Drug Administration (FDA) as Class II medical devices, meaning manufacturers must first prove to the FDA that such devices are at least as safe and effective as previous legally marketed devices before they can be sold for medical treatment purposes.

Traditionally used to treat decompression issues (commonly called “the bends”) in underwater divers, HBO2 has been deemed effective for treating other conditions, including carbon monoxide poisoning, air or gas embolism, non-healing diabetic wounds, thermal burns, and exceptional blood loss—the FDA currently lists 14 uses for HBO2, which is commonly prescribed to speed healing of wounds such as soft-tissue infections and crush injuries. There are also a host of HBO2 uses that have not been officially endorsed; athletes across a variety of sports have claimed HBO2 helps speed recovery from injuries or hard physical efforts, and celebrities, including Madonna and Michael Jackson, have famously touted the purported health benefits of their HBO2 regimens.

In the confined space of a hyperbaric chamber, though, fires can be catastrophic, experts say. “We know that an increase in pressure and oxygen concentration can result in increased burning and burning rates of material,” said Jonathan Hart, NFPA staff liaison for NFPA 99, in which Chapter 14 spells out safety procedures and precautions for hyperbaric chambers. According to a 1997 study published by the Undersea and Hyperbaric Medical Society, from 1923 to 1996, 77 deaths resulted from 35 fires in clinical hyperbaric chambers. Fires and explosions in HBO2 facilities worldwide have been caused by static electricity, electrical devices, chemical handwarmers, and other sources.

Woman with her comatose son undergoing hyperbaric oxygen treatment.

A woman with her comatose son undergoing hyperbaric oxygen treatment. The treatment is used to address an array of conditions not authorized by the FDA. Photograph: Newscom

That’s why experts stress that such chambers must be carefully built and maintained—a challenge as they proliferate. The number of hyperbaric chambers operated by hospitals or health care clinics increased from about 27 nationwide in the early 1970s to about 1,350 today, according to data from the American Hospital Association, cited by Workman. These facilities generally voluntarily comply with NFPA 99 and NFPA 101®, Life Safety Code®, to ensure Medicare and/or Medicaid reimbursement, he said.


But it isn’t the clinical hyperbaric facilities that pose the most concern. “That’s not where our problem really lies,” Workman said. “Our problem lies in those [facilities] outside that umbrella.”


Ten tips for AHJs

More than 18 organizations and agencies, ranging from professional societies to federal regulators, have responsibility for the practice of hyperbaric oxygen treatment. However, many local and state authorities having jurisdiction (AHJs), including fire marshals, have little knowledge of how hyperbaric chambers operate and the regulations that govern their use. Many may not even be aware that such devices are operating within their jurisdictions. Here are 10 points for AHJs to consider.

  1. AHJs should attempt to track the establishment and use of hyperbaric chambers operating in their jurisdictions, particularly those operating outside local hospitals or medical clinics. Tom Workman, director of quality assurance and regulatory affairs for the Undersea and Hyperbaric Medical Society and a member of the Hyperbaric and Hypobaric Facilities Committee of NFPA 99, suggests that AHJs visit such establishments and establish relationships with owners.
  2. NFPA 99 defines three classes of hyperbaric chambers, each with its own stringent design and operational criteria: Class A, which is a multiple-person occupancy; Class B, a single-person occupancy; and Class C, which is for animals or animal research.
  3. Low-pressure, portable fabric hyperbaric chambers are authorized by the FDA only for treatment of acute mountain sickness. While cleared by the FDA as a Class II medical device, these devices generally do not comply with ASME PVHO. Although only 11 states specifically mandate compliance to ASME PVHO, the requirements in NFPA 99 and NFPA 101 call for compliance with that standard and cover all hyperbaric oxygen therapy devices, according to Workman.
  4. Local AHJs have the authority to mandate that hyperbaric chambers in their jurisdictions be accredited by a recognized third party involved with hyperbaric oxygen education or operations, Workman said. Currently Utah and parts of the State of New York require such accreditation for medical insurance reimbursement.
  5. Be aware that patients undergoing treatment in hyperbaric chambers may not have the capacity for self preservation in an emergency. That is why chamber operators must be in visual or audible contact with patients or in sight of the chamber control panel at all times.
  6. Patients should not be allowed to wear street clothes into a chamber unless specifically authorized by the operation’s safety director.
  7. Patients should not bring cell phones, laptops, or other electronic devices into a chamber.
  8. If a chamber creates a concentration of more than 23.5 percent oxygen, both the device and the patient should be electrically grounded.
  9. NFPA code requires that oxygen be vented to the outside of buildings to prevent potentially dangerous 02 build-up.
  10. If AHJs observe what appear to be safety violations but are unclear on how to proceed, they can call the professional medical societies that cover hyperbaric medicine for clarification and guidance, including the Undersea and Hyperbaric Medical Society (919-490-5140 or 877-533-8467; and the American College of Hyperbaric Medicine (414-269-5340; AHJs who are NFPA members can contact the NFPA Advisory Service group at 1-800-344-3555.

Hyperbaric chambers have been established in alternative-medicine offices, spas, sports clubs, strip malls, and other settings where operators promote pressurized oxygen as a treatment for a host of conditions ranging from autism, multiple sclerosis, and AIDS to Alzheimer’s disease, Bell’s palsy, and depression—treatments not authorized by the FDA. Indeed, the FDA has issued consumer alerts warning of sham promises of miracle cures brought about by HBO2. Workman estimates there are about 200 freestanding or non-affiliated hyperbaric facilities in the U.S. Some are in clinical settings or medical office buildings and are run by physicians with appropriate medical staff, while others are in buildings deemed business-class occupancies.

That’s only part of his concern. Private citizens, some influenced by celebrity athletes—including former National Football League star Terrell Owens, who touted breathing pressurized oxygen as a way to recover from injuries—are purchasing portable, low-pressure fabric hyperbaric chambers, also known as “bag chambers,” for home use. The devices retail from $7,000 to more than $17,000 and can be set up and put into operation within hours after delivery. But Workman and others say the devices are not being manufactured, housed, operated, or maintained in a manner consistent with NFPA 99, increasing the risk of fire or explosion—and, as a result of the mechanical or physiological effects of higher pressure, injury or death.

There are no reliable figures of the number of these home-use chambers (also called mild hyperbaric chambers) currently in use, but Workman estimates there are “many thousands” of them—certainly more than the number of chambers that are in use in hospital- or clinic-based facilities. “So many people look up to professional athletes—they see a TV clip of a big football player with a chamber over his shoulder and think, ‘What’s good enough for him is good enough for me,’” Workman said.

The FDA classifies bag chambers as medical devices and authorizes their use only for acute mountain sickness brought on, in part, by exposure to high-altitude, low-oxygen environments. But manufacturers and operators, using cleverly worded ads, are promoting the bags for a variety of what are referred to as “off-label” uses, such as weight loss, anti-aging, or improved stamina, as well as for more serious conditions.

What is of key concern to life-safety officials is that the bags do not currently comply with the design and fabrication safety requirements of ASME's Safety Standard for Pressure Vessels for Human Occupancy (ASME PVHO) and/or NFPA 99. The bags are designed to be used with compressed air, but many users connect them to oxygen concentrators. NFPA 99 requires that the exhaust of all hyperbaric chambers be piped to the exterior of buildings. Without such venting, oxygen can build up to dangerously high levels in both the chamber and the immediate vicinity, Workman said.

It all adds up to a significant fire-safety concern. “We don’t know what the oxygen percentage can be inside the bag—if the oxygen level is too high, flash time is reduced and you don’t have any response time in a [fire] event,” said James Bell, technical supervisor of Hypobaric & Hyperbaric Safety, Intermountain Medical Center & LDS Hospital, and chair of the Hyperbaric and Hypobaric Facilities Committee of NFPA 99. NFPA codes also stipulate that if the oxygen inside a chamber is in excess of 23.5 percent, the patient as well as the chamber must be electrically grounded because a static charge could increase the risk of fire.

There are other risks as well. In June, 2011, in North Carolina, a 19-year-old male being treated for autism suffocated in a fabric chamber when a valve became disconnected. The family, who allegedly learned of the device at an autism conference, sued the manufacturer, claiming it marketed the chamber as safe for unsupervised use despite knowing the valves could disconnect. The case was settled out of court. “Your lungs are actually really fragile,” Bell said of the physical hazards associated with the devices. “It only takes a couple of inches of water pressure or half a [pound per square inch] to injure your lungs.”

Other dangers include wearing non-approved clothing. NFPA 99 requires either cotton or cotton-poly clothing inside chambers to minimize the hazard of static electricity, which can be more easily generated by some synthetic fabrics. Items left in pockets, such as mobile phones, can also present static electricity hazards inside chambers. Workman cited a facility where patients were issued portable CD players to take inside the chamber, a practice he described as a “significant fire risk.” In July 2014, a woman in a New York City spa found herself trapped in a $100-per-hour inflatable hyperbaric chamber and could not summon staff. She texted a help message to a friend, who alerted firefighters. NFPA 99 requires that during chamber operations with an occupant in the chamber, a chamber operator will be physically present and maintain contact with the occupant. “Someone needs to be there who is qualified to be there,” Bell said.


Physicians may legitimately prescribe HBO2 for off-label uses; the FDA does not regulate the practice of medicine. The issue is how such uses are marketed. “The FDA has gone on record publically with several warning letters to facilities for promoting their chamber for off-label indications,” Workman said. Compounding the Martinisi tragedy in Florida, for example, is that HBO2 has not been clinically determined to help cerebral palsy. The secondary market—where chambers are sold through venues like Craigslist—is another area of concern; a device that may have originally been set up and used according to code may not be used appropriately by a new owner.

Workman and others want to see greater NFPA code compliance by fabric bag manufacturers, and for local authorities to be more aware of the potential hazards of chambers in non-clinical settings. When a hyperbaric chamber is installed in a hospital or clinic, occupancy and health safety codes must be met. In cases of non-affiliated chambers, fire marshals and others may not even be aware that chambers have been installed and are being used in their jurisdictions, Workman said.

Former Major League Baseball pitcher Rafael Soriano prepared to get into a hyperbaric chamber for home use.

The popularity of hyperbaric chambers for home use—also know as mild hyperbaric chambers or "bag chambers"—has been fueled by endorsements from professional athletes, including former Major League Baseball pitcher Rafael Soriano. Photograph: Newscom

Workman believes facilities in malls and sports clubs should adhere to the provisions of the Life Safety Code even when they insist they do not represent a health care occupancy. In states that adopt NFPA 101, such facilities may be covered by Chapter 8, which applies to hyperbaric chambers and specifically refers to NFPA 99. “If NFPA 101 is adopted, then there is a regulatory mandate for authorities to use when enforcing codes through plan review or routine inspections, regardless of occupancy type,” Hart said.

And that makes a difference. Operators who follow NFPA code “have a pretty good record,” Bell noted. In North America, from 1968 to 2009, there were no reported deaths related to fire in any facilities operating hyperbaric chambers that complied with NFPA codes, Bell said.

An investigation of the Martinisi case in Florida found that while the refurbished chamber had been built to code, it was neither properly maintained nor operated according to code at the time of the fire. The device was not grounded, the occupants were wearing street clothes, and the intercom was not working. The grandmother apparently adjusted a cushion, and a buildup of static electricity generated a spark—enough to trigger a violent fire in the oxygen-enriched environment. She banged on the chamber to get someone’s attention, but when an attendant did appear, the chamber had to be depressurized for 90 seconds before it could be opened. Prosecutors said the chamber was not designed to hold two people and that it had not been properly cleaned. Investigators found numerous electrical issues and broken indicator lights covered with electrical tape. “In my opinion, the accident may not have happened if the facility had been diligent with following the minimum code set out in NFPA 99,” Bell said. “The affidavit from the sheriff’s department reads like a list of failures to meet the code.”

Once the device was installed, “no one was coming in looking at it,” Workman said. “There was no reason for the fire marshal to come back”—a fact, he said, that underscores the need for more education and greater awareness of the risk of non-code-compliant hyperbaric chambers.

STEPHANIE SCHOROW is a writer in Boston. Top Photograph: Newscom