Thank you for producing this. This is excellent and important information.

As someone who has lost multiple friends in diving, including three people I knew who died in rebreather accidents, this subject hits close to home. Most recently, I lost my friend Luis Gonzalez on a CCR and conversations like this matter.

I’ve also done a series on my own YouTube channel with interviews featuring Brian Carney and Jeff Bozanic about rebreathers. What struck me was that I got two thoughtful but very different views from two people I respect in the diving industry. One side sees rebreathers as something that should become more mainstream. The other view is that maybe rebreathers are not mainstream, and perhaps never should be.

I dive a rebreather, but I do not teach rebreathers. I also think we need to be honest about the culture around them. Sometimes in technical diving there is almost an ego element: if you are not on a breather, you are treated like you are not one of the “cool kids.” I was at Ginnie Springs this morning and saw plenty of that attitude. We need to change that mindset.

You do not need to be on a rebreather to be a serious diver. You do not need to be doing big technical dives to be a good diver. Open circuit is still valid, capable, and often the smarter tool for the dive.

I’ll be sharing this not only with my dive friends, but also with my students. Even for divers who never plan to touch a rebreather, this is important information about risk, mindset, decision-making, and humility in diving.

Great work, and thank you again for putting this out.

Refused to be rushed is such a good rule. All certification classes give you these checklists and the importance of doing these checklists, but they don't really cover the realities of actual diving: time crunch, either from the circumstances or the social reality. Being rushed is a huge reason people (and myself) make mistakes or skip checks.  The natural extension of this rule is DON'T RUSH OTHER PEOPLE.

I wrote an article maybe thirty years ago where I said that I stay on the loop for 10 minutes before getting in the water. For shore diving, I walk from the car to the water on the loop. If I have to come off the loop for any reason, I do another 10 minutes. I want to see that it's supporting my life for at least that long before I take it underwater. That catches most (not all) of these sort of issues.

I think any hobby/athletic activities that we do for long periods of time, where we become very experienced at our chosen sport, we forget that our bodies are aging, in subtle ways that we aren’t aware of, and we hit a tipping point inside. At some point, we’re older, we’re more stressed, we have things on our mind, and we go on “autopilot,” and don’t even remember how we drove home.

Being organized and following your own personal checklist for your chosen sport. Mine was horseback riding. I made sure my husband’s horse’s tack, the bridle and saddle, was correct, the girth tightened, and he got mounted first. Then, I checked each of my children’s horse’s gear, double checked everything, and got them mounted up. This was to be sure there was an adult mounted and ready before they’re mounted up, in case of one of the children’s horses acting up. Finally, I checked all of my horse’s bridle, reins, breast collar, saddle bags, and girth are all tied down correctly, and tighten the girth for all the other 3 horses again, before tightening my girth, and FINALLY mounting up. I was the most experienced horse person and I wouldn’t have been able to mount my own horse, if I hadn’t personally seen to all the gear. I taught my sons what I was doing, and they could do everything by the time they were teenagers, but it’s still ALWAYS better to check your horse and tack yourself. Never rely on someone else to saddle and bridle your horse for you.

I also knew my body was disintegrating from bone loss. I rode my horse for the last time in June 2009. I’d herniated 2 discs walking, and ended up having major back surgery in 2005. Then had right sacroiliac joint surgery in 2020, and left sacroiliac joint surgery in early 2022. I have 12 titanium screws, 6 monarch titanium screws from 9/2005, 3 from 10/2020, and the final 3 in 2/2022. I’m in full osteoporosis and osteoarthritis in every joint. I miss my horses but I physically can’t ride as my body hurts constantly. They all passed by 2011. We rode all over North Georgia and the tri state area, camping and riding everywhere. I think my body survived so long was because I did ride horses and the physical motion helped keep me functional for much longer. It’s the same principle as physical therapy for disabled children. They get more out of being led around an arena for an hour, than if a human physical therapist worked their body for 2/3 hours. I was having injections of Toradol without an appointment, from 1994 to 2002. I moved from Georgia back to Arizona in 2002. I herniated both discs in late March 2005. Surgery was 9/2005.

This diver sounds like he was in a hurry to be first in the water, as he always wanted to be first in the water. Right there says your ego is bigger than your brain. He was older, had done this a thousand times, and no one knows if he was developing the signs of dementia. It doesn’t have to be serious mental lapses, but short term memory gaps are the worst. He wasn’t slowing himself down to make himself check all his equipment. I’ve watched divers who look for vehicles and human bodies inside, and even if it’s a small pond barely 8’ deep, they double check themselves, and then have their partner check the setup before they go underwater. It certainly doesn’t take but a few seconds being in a hurry, especially the more experienced one is, the easier it is to get sloppy, and make a very simple mistake that can have catastrophic consequences. The whole accident was over in less than 15/30 minutes before he was noticed as in distress. I’m very sorry for his loss. May he RIP, and Many Blessings to you, to his family, his friends and all who read this.

Thank you so much for telling us this story.  My buddy died Feb 10, 2025 on a CCR in our local quarry doing a dive we had done hundreds of times.  The Medical Examiner listed the cause of death as an AGE due to rapid ascent.  That was the cause of death, but not the cause of the accident.  He had jusr returned ffrom a month of work and was anxious to get back in the water.  He had some issues with his unit, solved them he thought, and proceeded with his dive. Eighteen minutes later he popped to the surface, loop out, not bailed out, dead.  We will never know all the details, but his off board bailout was stowed and full.  I believe that he had a CO2 breakthough, felt it and hit his inflator, passed out, and rapidly ascended.  I believe rushing and distraction were the causes.  My mantra is NO RUSH and IF IN DOUBT BAILOUT and stay bailed out.

“It could have been me”
Humility

Thank you for sharing this
I’m sorry for the loss of your friend and please share condolences with his family

I have been OC trimix since 2004 and CCR mod 3 since 2006 (at a relatively young age of 29yrs old back then)

I have dived all the Malin head wrecks over those years from 2005 to 2013. But we lost a diver on a trip to Malin on the same boat as you were on (similar situation) but this diver made it to the wreck in 90 meters before passing out.

He was not known to me personally other than being on the trip. Due to the depth, ourselves had to go back and dive the same wreck the following day and try and find him, which some of the lads did and they recovered his body.

I continued deep stuff for a few years after. But my heart was no longer in it & i was left with a nagging feeling that the more I carry on doing this, the more chance it will be me one day & I did not want my wife getting the knock on the door saying that I was not coming back.

In 2013, I came home from a trip and put all my gear up for sale. I was done. Something that had been a huge part of my life and made me me, was over. I was not willing to take the risk anymore

Over the years I had had inner ear bend on deco from a 70m dive(came it at 30m on deco & cleared by the time I got upto the 12m mark), a DCI hit after 5 days mixed gas diving that required the chamber (the hit happened after clearing all deco and  about 20 mins on surfacing) I carried on deep diving and completed 100’s of dives in the 60-100m range in between and after those incidents without issue. And always put it as an occupational hazard and it never put me off.

But the longer I was around those diving circles the more I heard and experienced of very accomplished and experienced divers die on dives.

I have done all i wanted to achieve by doing certain deep wrecks and the bottom of the blue hole at 117m & even a cave dive at 102m. but for me I am no longer willing to dive past 50meters (and that would have to be for a very certain wreck or dive site) and no more than 20mins deco max.

I am more than happy now diving with my wife recreationally upto 20-30m range single tank no pressure or stress. Jump in get wet, swim around for an hour and get straight back out.

I’m 50 next month and I have no desire to ever get back into deep gas diving. Been there, done it got the T shirt. But I realised the longer you do it the more chance of myself becoming the statistic.

The younger me was not interested in doing anything shallower than 60meters.

Sorry for your loss. You can be the best in the world and still make a mistake. I dive nearly every day and the greatest enemy to a diver in my mind is assuming safety by repetition. This is a great lesson for everyone in the diving field. I have a through checklist that i complete daily regardless of how deep or shallow we are diving.

Thank you for get some learnings of the tragic with James! I‘am Diving the AP Inspiration since 4 years and it’s my first rule to stay calm and focused to preparing my unit before the dive. Sometimes my buddy’s are waiting for me, but I don’t hesitate or get in a hurry. It’s an important thing when you are diving in a group of divers to prepare in your way and procedures in the time you need without getting hurrying . That’s the psychological factor in diving and especially for Rebreather diver  ! Greetings from Germany 🙋‍♂️

Thank you, Ken, for sharing this, and I’m truly sorry for your loss. ❤
I’m currently looking at getting into CCR diving, and watching your video really hit home for me.
Just recently, at a dive show in Sydney, I met another diver who does something very similar. He has “AIR ON” written on his fins as a simple but very important reminder to stop and recheck his PO₂ before entering the water.
At the time, I thought it was a great idea. After watching your video, I realise just how important that simple reminder could be.
As someone preparing to take my first steps into CCR diving, this is a lesson I will carry with me. CCR diving leaves very little room for complacency, and sometimes the simplest checks are the ones that matter the most.
I don’t ever want to find myself looking back and wishing I had taken an extra few seconds to check something that could have saved my life — or, even worse, have my family and friends left wondering why I didn’t.
I’d much rather take an extra minute to check, recheck and be absolutely certain than spend the rest of my life with regrets.
Ken, thank you for having the courage to share your experience. If your video makes even one diver stop, think and take that extra check before getting in the water, then your message may help prevent another tragedy.
This is a lesson I won’t forget. ❤🤿

Easily, one of the most succinct dive accident briefs ever done.  DO the checklist, don't just read it. Stay ahead of the dive. Task saturation is deadly.  Yes, it can happen to me... and you.

wow this is random 17 minutes video lesson that really blows my mind up. great video

As an aviator, I was thinking about procedures and checklists throughout the video.  As they used to say, most procedures are written in blood.  As a now retired airline pilot, I was always amazed at how many experienced copilots were cavalier with checklists. Sometimes people recite them from memory instead of looking at the printed card.  There's also expectation bias.  This affects what you perceive you see vs what is actually there.  Never rush.

As an avid diver and instructor,I made the decision not to get into tech diving.   Just not worth the time, money and significantly increased rick factors.  I have done thousands of dives and very satisfied with that.   I appreciate what you guys do, but no thanks.   I am also a pilot.  We often talk about the holes of the Swiss cheese lining up.  They did for James.  So sorry RIP

This is truly a sad story. I always find myself checking the divers gear next to me before any dive. Old Army habit to check your buddy even when they aren’t your “buddy”. I tend to dive warm water tours these days versus my old tech past but I think it’s as important given how the divers around you likely have far less experience and make simple errors that could lead to not so simple issues underwater. It was just odd to me that the entire boat was sole focused and never cross checked. It’s like dropping a chock of chutes and not checking the guy in front of you. Checklists for sure and follow them. But also just do a simple check of the guy next to you and make sure they at least have proper air and stuff is on.

This is why checklists and flow checks are key.  And need to be done , in order, every time.  Suspect experience bred complacency.  Dive rebreathers like you're flying a plane.

Thanks for the video. Whenever I see a dive accident video, I think about what I personally do to prevent one. My unit came with two checklists engraved on metal plates, which I only unclip from the unit just before the jump, and I've followed them rigorously since my first training. Its " Closed Check" and "Pre-Jump" Checklist.
When I travel and dive with other CCR divers, I see mayn do a Closed Check but I'm always surprised how rarely they even have Pre-Jump checklist. It makes everything easier and safer in my opinon, no matter how much experience you have.

Here is the content of the Revo Pre Jump Checklist:

Bail-out
Open bail-out and check pressure; breathe the bail-out and check pressure; check connections.

Diluent
Open diluent and check pressure; ADV suck test; add diluent manually (all sources) and check pressure; inflate wing; inflate drysuit.

Oxygen
Open O2 and check pressure; Shearwater on, low setpoint / solenoid; add O2 manually (all sources) and check pressure; rEvodreams/Nerd on with PPO2 above 0.7; check batteries on both rEvodreams/Nerd and Shearwater; pre-breathe 5 minutes (or until RCT exceeds 0:45) while watching PPO2; confirm gases are set in the Shearwater.

The Bail-Out I usually do before I put the Bailout in the water, if I dive from the shore. Or before I put them on the dinghy, depending on the situation. And of course you can't breath hypoxic bail-out on the surface.
The Diluent and Oxygen part I always do with the unit already on my back, I never close the O2 or Diluent again (and the Revo even has an Orifice, so it will put Oxygen in all the time when the O2 tank is open but its very little) or turn the unit off (then the RMS wouldn't work if I would jump straight in). If the delay is too long and I want to turn it off, I simply do it again. I think this is a very simple procedure everyone could do and you really don't loose much time.
With the RMS the pre-breathing takes usually 1-3 Minutes and the rest of the checklist is completed very quick.

Sorry for your loss bud, hope we all learn something from this.

You know, this really makes me content that I’m happy snorkeling off the beaches here in South Florida. I’ll leave all this Tri-mix stuff and deep diving to you pros and good luck to you.

I know nothing about diving but what a good lesson! Can be applied to anything. Well done and I’m sorry about your friend.