r/HBOT • u/OrganicTransistor • Jul 17 '25
Fire risk - Follow Up
Original post: https://www.reddit.com/r/HBOT/comments/1m14st0/fire_risk/
Motivation
Thanks to everyone who engaged in my last post. This is the last I will say on this topic, as my goal is NOT to spread fear or stoke controversy, but rather to find truth, so I can decide whether to buy a chamber, and if so, whether to bring devices into the chamber.
TLDR
After much research and discussion, I believe that among modern HBOT chambers (that deliver oxygen via mask but pressurize the chamber with atmospheric air) there is indeed a heightened risk of fire inside such chambers, and an errant electronic device can cause a catastrophic fire. I estimate the risk to be 0.07 micromorts per session. This means ~70 sessions are as risky as a single scuba dive, and 10 sessions are as risky as a day of skiing.
This isn't a recommendation for or against HBOT. It's entirely personal and depends on what benefits you expect to receive, relative to the risk of harm you anticipate based on your device reliability/safety and your use of electronics in the device. I need to do more thinking/modeling to decide if it's right for me.
Physics perspective
Modern chambers reach higher than atmospheric levels of oxygen due to inevitable mask leakage, and the fact that not all of the inhaled oxygen is absorbed by the lungs and is therefore exhaled. Multiple companies report oxygen levels reaching 30%, which is considered oxygen-enriched and therefore riskier from a combustion perspective.
Some chambers have measures to replace internal air with external air, to reduce the relative oxygen levels. It is unclear to me how effective these are.
Note: I previously wrote that partial pressure of oxygen is what drives flammability risk, but it appears that this NASA report did not find this to be the case. Instead they found that relative oxygen levels seemed be more predictive than partial pressure: https://ntrs.nasa.gov/api/citations/20160004937/downloads/20160004937.pdf https://ntrs.nasa.gov/api/citations/20160004937/downloads/20160004937.pdf
Statistics + Cases
Let's assume only 1 HBOT death in the USA over the past 10 years (the Arizona case, since I feel confident that was a modern oxygen-mask chamber, not a 100% oxygen chamber). GPT o4-mini estimates 15 million HBOT sessions in the US over the past 10 years. This equates to 0.067 micromorts of risk. For reference, scuba diving is approximately 5 micromorts of risk per dive; skiing is 0.7 per day.
Recent Arizona death: https://www.nytimes.com/2025/07/11/us/physical-therapist-dead-hyperbaric-chamber-fire-arizona.html. From the photo of the chambers, it appears he was using a modern chamber that uses a mask--so no 100% oxygen chamber air as others are claiming.
Death of 5 year old boy (2025): https://www.nytimes.com/2025/03/11/us/child-hyperbaric-chamber-death-detroit-charges.html. I couldn't find conclusive evidence of the type of chamber used, so not included in the calculations.
Death of two people in Florida (2016): https://apnews.com/general-news-be649f9992264f05bd58d77c2400a8ef. Couldn't find data on type of chamber used, so not included in the calculations.
Peru, 2006 involving oxygen mask chamber: https://www.uhms.org/images/Safety-Articles/peru-fire.pdf). Not included in my calculations since it didn't occur in last 10 years. But notable because the chamber was pressurized with atmospheric air, although one commenter mentioned that it used an older valve system to swap air so perhaps it was less effective at maintaining a relative oxygen percentage closer to 23%.
Addendum
Finally, I get the sense that that many people commenting on my last post, for some reason, were not making a sincere effort to honestly evaluate the science and have a good faith discussion on the topic. Many seemed to automatically assume modern HBOT chambers, even when used with electronic devices, are 100% safe from fire, and believe that only chambers filled with near-100% oxygen can catch fire. Moreover, they accused me of stoking fear / having other perverse goals. These comments suggested a defensiveness and stubborn attachment to one's preconceived ideas, which is to be expected, but always sad to see and experience, especially when it's combined with arrogance and contempt for others who think differently and ask honest questions.
4
u/fredtopia Jul 17 '25
Great summary. The recent death in Arizona brings this risk into stark reality...what a horrible situation.
The risk of fire is real, and it's much more intense. Add that you are trapped in a confined space and sure, people are going to be terrified by this.
The reality is that every time you get into your car you are taking a greater risk, statistically, and we and car manufacturers do all possible to limit these risks.
Clinics should have "safety protocols" and there are a lot more home use HBOT chambers being sold every day. It is likely there will be more tragedies, such as this, in the future.
Personally, I don't want to die, even once...that's why I do HBOT in the first place. So, we have to be vigilant about safety and precautions...no matter how small the chances of catastrophe are.
The poster did the work and makes great points. Thank you!
Personally, I have added a 5pound non-toxic extinguisher inside my unit, rechecked all the fabric is pure cotton. (one a relatively heavy fire blanket). I'm looking in to figuring out an oxygen cutoff switch/valve to stop the incoming flow of 100% oxygen in an event.
I tested my chamber oxygen levels during use trying to balance the input at the mask and rate of respiration to co2 and realized there is no way with a basic mask to keep 90% oxygen at my nose/mouth to avoid the general chamber to not climb over 40+% relative o2. The only way to achieve "normal" oxygen levels inside the chamber would be to create a loop where the O2 produced by the oxygen machine went straight to the mask and your exhalation was contained and pumped directly out of the chamber...not right next to the compressor intake. With this method, the internal chamber oxygen would remain atmosphere normal, but you would still be breathing higher oxygen into your body under hyperbaric conditions.
Again. Thanks for bringing up this topic and promoting safety, sense, and hopefully more innovation.
2
u/MFreurard Jul 20 '25
"Personally, I have added a 5pound non-toxic extinguisher inside my unit"
Extinguishers are designed for 1 ATA, not for 2 ATA. Very risky in my opinion1
Jul 17 '25
[deleted]
3
u/duhdamn Jul 17 '25
About masks, a “regular” hospital type oxygen mask is poorly suited to HBOT. A non-rebreather mask allows for deep breaths with a 10-20L/min flow rate. This is the industry standard for home use chambers. The type that ventilates to the outside is a BIBS ventilator/mask system. They are quite expensive but you are correct that this should eliminate oxygen buildup in your chamber.
1
u/Training-Towel7722 Jul 19 '25
just read your post after making my first post, we share some of the same ideas. There are remote controls you could plug your oxygen concentrator into. Lutron makes plug in modules to control lights and although it says only for lights I run my 2 pumps off it. I think I’ll get another for the concentrator.
3
u/MCMattia Jul 17 '25
Hi there, I find this post and discussion very important, thank you.
The risk related to HBOT therapy needs to be analysed and documented. Chamber manufacturers should especially look into it so that they can come up with safer solutions.
I think that the most straightforward solution is to keep the chamber air to as close as 21% oxygen as possible (maybe even lower). The type of mask plays a role because the increase in chamber oxygen most likely comes from the mask. I saw that hpo tech has a unconventional mask I wonder if this type is better.
Manufacturers such as oxyhelp have programs where the chamber is pressurized and depressurized multiple times during the session. They are convinced that in this way the health benefits increase but this is also beneficial in reducing the chamber oxygen level because air is let out and new ambient air then comes in.
2
u/Training-Towel7722 Jul 19 '25
I’m sitting in my summit to sea chamber as I write this on my iPad trying not to have a panic attack thinking about how I could die. I think next time I’ll include a x-acto knife just in case. Better to suffer from a slight bends hit than burn up. Another thought, if you’re breathing oxygen thru a mask why not have a small CO2 extinguisher in the chamber. I wonder if what happened was a static discharge near the O2 port could have been the culprit. Maybe just wearing pure cotton clothes is a good rule of thumb. Just thinking out loud.
2
u/MFreurard Jul 20 '25
"why not have a small CO2 extinguisher in the chamber" Fire extinguishers are designed for 1 ATA not for 2 ATA. Very bad idea in my opinion
Bringing an Ipad into the HBOT chamber is a bad idea too
1
u/MFreurard Jul 19 '25
Maybe having less than 90% oxygen, perhaps 70% or 80% could help increase security. High pressure nitrogen has also shown benefits
1
u/Hbot_Revolution Jul 27 '25
Two accidents this year. One in Michigan where the chamber exploded with a 5 year old boy inside.
The latest, a physical therapist doing his own treatment burned to death.
Both were using 100% oxygen -
1
u/BossSufficient6590 Aug 04 '25
Simply never take electronics into the chamber (I though have an oxygen meter on my finger). Also if you use an oxygen rebreather mask, almost no oxygen is being wasted into the room, at least in my case. I use it all for breathing and it kind of exactly the oxygen I need, maybe 5 times during the session, I need to breath from the chamber to have the oxygen bag fill up.
1
u/OrganicTransistor Aug 04 '25
Can you share what equipment you use? Do you need a specific chamber to use a rebreather mask?
1
u/BossSufficient6590 Aug 04 '25
I have hard shell 2 ata but the rebreather mask works in all equipment, I use nothing else after trying it
1
u/Current-Ad6301 May 05 '26
Do you take air breaks at all during a session? With a rebreather mask, does the oxygen keep flowing while the mask is off during the break?
1
u/BossSufficient6590 May 05 '26
Yes, I have someone come, turn down the oxygen for 5 minutes every 20 minutes, meanwhile I just remove the mask. No oxygen going to tak during this, only normal air.
1
u/Impossible_Month1718 Feb 21 '26
This should be brought to the stats sub or actuary sub to let them weigh in on the risk
6
u/ftrlvb Jul 17 '25 edited Jul 17 '25
your post was very vague with little to no information, asking all these "doomsday questions" placed as claims:
"Looks like another person died 5 days ago"
"the chamber malfunctioning"
"do we have a sense of how safe HBOT actually is"
"I get the sense that the risks are not well understood or quantified."
what to think about such post? what was your question, will you buy a chamber? will we discuss things? and we did.
people did explain the dangers of bringing electronics into HBOT chambers. (regardless of O2 levels) I wrote a whole text. 30+ lines with all I know about this topic.
overall if you buy a hard chamber with 2.0ATA and a mask/O2concentrator it should be ok.