Monthly Briefing April 2025

Full details of the investigation into the January 31, 2025, fatal hyperbaric chamber fire are yet to be released. However, sufficient information has entered the public domain through publication of transcripts from a “swear-to” hearing (in which the investigators made a solemn promise under oath to tell the truth before giving testimony) and the televised arraignment of those charged in connection with the death of the child, to offer several observations.

Critically, there was a failure to ground the child to the chamber and, equally damning, this was not an isolated omission. As incredulous as this seems, it was this facility’s standard operating procedure based, in part, on its hyperbaric safety director purportedly undertaking some form of testing, the results of which, he concluded, invalidated any need for patient grounding. His conclusion, and the resulting policy decision, were firmly at odds with rational thinking and prevailing authoritative safety standards.

The child was observed by a video monitoring system to be moving around, eventually causing a sheet to expose the underlying mattress. At this point a static electrical discharge spark/flame was observed between the mattress and the child’s knee/lower extremity. Some had previously suggested that perhaps a battery powered device represented the ignition source, but this was not the case. It was the discharge of the child’s accumulated static electricity, precisely what a grounding system is designed to prevent, that ignited the chamber contents. One of the investigators stated that the chamber was completely engulfed in flames within approximately three seconds of the spark/flame being observed. In addition, there was no verification of the child’s clothing tag per surveillance camera footage to determine if it was 100% cotton.

This case has remarkable similarities with the Lauderdale-by-Sea, Florida, 2009 fatal monoplace hyperbaric chamber fire. It was here that another young child perished in a chamber not being maintained in accordance with the manufacturer’s recommendations, he was likewise ungrounded at the time, and the cause of the fire reported to be electro-static discharge. The 2009 fire proved to be double fatality. The child’s grandmother, who had routinely accompanied him in what appeared to be many months of hyperbaric “sessions” (I cannot in good conscience bring myself to say treatments as there was nothing therapeutic about them, while the Michigan Attorney General called them ‘so-called debunked treatments’ when discussing the 2025 fire) also succumbed. Both the hyperbaric physician and hyperbaric safety director pled guilty to two counts of manslaughter and one count of aggravated manslaughter in the 2009 fire.

Not only should these fatalities not have occurred, but neither child should have been inside a hyperbaric chamber in the first place. According to the courts, both families had fallen prey to unscrupulous individuals who focused on bringing cash in the door over safety and any realistic expectation of therapeutic gain. One might hope that the courts’ admonitions will give pause to others who would otherwise fall prey to false claims of benefit by off-label hyperbaric profiteers, of which there are many.

An additional safety consideration beyond all-important patient grounding related to prevention of electro-static accumulation and discharge is chamber relative humidity. (RH) Humidification is an effective way to prevent its build-up. Dry air/gas is an insulator, moist air/gas a conductor. Water conducts electricity because of dissolved ions (such as salts and minerals, within it) that allow for the movement of any electrical charge. This is not water molecules per se. Pure water for instance is an ineffective conductor. Oxygen entering the monoplace chamber is dry. Chamber RH will rise during occupancy due to insensible moisture loss though the skin (sweat being higher in dissolved ions than regular tap water represents an even more effective conductor) and through respiration. Lower chamber oxygen flow rates allow chamber RH to increase (as moisture accumulates), the reverse being true with high flow rates. We had earlier found the Sechrist 2500 monoplace hyperbaric chamber RH to range in the 20’s with high (450 lpm) flow rates during occupancy, a level that would allow any friction to produce an accumulating static charge. When flow was reduced to its lowest level of 240 lpm (more modern chambers have lower rates) RH reached the 60’s on several occasions. Some of you may have even seen RH levels reaching 100% when the inner acrylic fogged over. It is generally considered that with RH levels between 45-55% static can still build up but at a reduced level as it ‘leaks’ to ground through this moisture content. Levels above 55% RH are considered to largely eliminate static build up. So, you should endeavor to keep monoplace chamber oxygen flow rates as low as possible once at treatment pressure, recognizing that higher flow rates are preferred during compression to more effectively convert from an air to an oxygen environment. If a patient complains of being cold, don’t provide another blanket (think the 1996 monoplace chamber fire and resulting structural failure), lower the flow rate. Better still, endeavor to maintain flow at the low end of the scale as an operating policy.

Dick Clarke, President

National Board of Diving & Hyperbaric Medical Technology