The first deep rebreather dive using hydrogen: a gateway to deep exploration? - Simon Mitchell

[@JacobProbasco]

"we largely resolved these concerns by ignoring them" 😎love it

[@mithrandirthegrey7644]

Sounds moronic to me. Imagine your pilot saying this before you take off.

[@Drimirin]

@@mithrandirthegrey7644 Sounds similar to things a certain submarine pilot was saying not so long ago.

[@pieroo7]

@@Drimirin what happened to him?

[@samhodge7460]

@@pieroo7 He and his four passengers died from a catastrophic implosion. Look up the Titan submersible. The pilot/founder of the company ignored countless safety regulations in the name of "innovation".

[@mithrandirthegrey7644]

@@pieroo7 He's talking about the Titan submarine that imploded near the wreck of Titanic.

[@Jason-vn5xj]

I’m not a diver, but I was a respiratory therapist who worked in a hospital hyperbaric medicine area for a while. This is absolutely bananas and I love every minute of it. So awesome.

[@divingtalks]

That’s a cool comment! Take a look at the other Talks, many more interesting topics.

[@bobm2331]

That presenter was as focused and clear as any I've listened too. Also if there's a level beyond amazing this was it. Well done folks.

[@divingtalks]

Thank you for your kind words. This is the type of content and presentation skills we want to have on our show. Watch some of the others. More interesting content being shared in the Diving Talks KZbin channel.

[@R.Daneel]

I came to say the same thing! What a great presenter. I'd have watched an hour on the advancements in paint-drying technology.

[@divingtalks]

Check out the other Talks. There were other really interesting ones. For example the the two about the underwater habitats: #DEEP by Phil Short - another highly skilled diver, and #PROTEUS by Brian Helmuth. Both worth watching.

[@minibus26]

Very interesting. Thank you for sharing and feedback. For my part, during my dive at -312m in Font Estramar cave, with a trimix 4/86 : I only felt very weak HPNS. Exercises allowed me to check my lucidity at different strategic depths. Concerning the density of the gas breathed of 8.56 g/l ( -75,60m air equivalent ), the Joki being a very flexible rebreather, I did not feel any discomfort at -312m. Regards Xavier Méniscus

[@divingtalks]

Thank you for your comment. That strategy you used to check how you were during the dive is a very interesting piece of information. I hope we can discuss other important topics, Xavier, in a near future. 😉

[@martincook6318]

Very impressive. My uncle was part of the Royal Naval Sat exploration team and was the first in the world to have a general anaesthetic at 300M albeit in a chamber. All this stuff interests me. Thanks

[@kinnymane8593]

I’m not even a diver and this BLOWS my mind!!! Humans go hard I love watching innovation and the limited get pushed

[@divingtalks]

An incredible achievement. Watch some of the other talks. They’re great!

[@wildxplorwild7469]

Heli access/remote/cold/camping/cutting edge tech diving/super exotic gas mixing/water tank habitats/ 16 hours of cold water deco. Zero tolerance for a failure 250 Meters/800 ft bottom Hpns In the 80s I worked on many Sat vessels in the North Sea so I’ve an idea of the reality of these dives. Gobsmacked Fkkkn A Really impressed

[@nickb220]

what

[@AsianManZan]

Don’t worry buddy. Fellow diver here. I get you. I did the same in the gulf. I moved to inland and joined the union. Way different. Enjoy your retirement!

[@divingtalks]

It was quite an achievement, indeed. Check out the other Talks. There were other really interesting ones. For example the the two about the underwater habitats: #DEEP by Phil Short - another highly skilled diver, and #PROTEUS by Brian Helmuth. Both worth watching.

[@arwo1143]

12:40 I kinda feel like the room didnt appreciated that joke appropriately

[@horwoodg]

You have to be of a certain age I think, I got it and I'm getten on in years.

[@divingtalks]

Check out the other Talks. There were other really interesting ones. For example the the two about the underwater habitats: #DEEP by Phil Short - another highly skilled diver, and #PROTEUS by Brian Helmuth. Both worth watching.

[@mirandahotspring4019]

Brilliant! Great to see these new innovations happening in New Zealand. I remember one of the early dives into the Pearse resurgence by Kieran McKay, Pete Hobson and Dave Weaver, that ended so tragically for Dave Weaver back in 1995. Things have come a long way since then.

[@johnstreet797]

If you are going to mix hydrogen and oxygen in a plastic bag always put the oxygen in first. Don't ask me how I know that....

[@AstralWarrior]

How do you know that? 🤔

[@xiro6]

​@@AstralWarriormaybe static discharge blew it, while oxigen will just burn the bag. But maybe, i really dont know.

[@parkershaw8529]

Simply because we are in an oxygenous atmosphere.

[@nastropc]

Otherwise it will float away?

[@karlmckinnell2635]

Any thoughts on a fuse🤔

[@jonnyjohn2321]

“We dealt with those problems by ignoring them” this is a sentiment I can co-sign, love the … lecture ?

[@jerryphillips6809]

Middle aged cold water divers may want to check out a documentary on "core body temperature recovery". The study was preformed on an older gentlemen climbing on Denali, his core temp recovery was substantially less than the younger mountain guides. I would imagine the same issues would be at play in extreme diving scenarios.

[@kaviyaneskandari2316]

ended with a total banger

[@freddupont9605]

Pr Simon Mitchell...he's a living legend in both deep technical diving and anesthesia. Dr F.D.

[@jeffp.8718]

For the rest of us, theres a snorkel. Beyond that theres the common scuba tank. And if you still want to push the boundries watch a cave diving video on youtube.

[@bullschitt3666]

We used to push our common scuba tanks with air down to 220 ft. All this tech stuff seems dangerous to most, but for what we were doing it would have been much safer 😊

[@gasdive]

​@@bullschitt3666 haha, I was diving air to 260 ft and had friends diving 330. Helium was an absolute godsend.

[@Namibiets]

Aussie hydrogen mixture backyard testing is the best testing period!

[@izelennkhan]

Did you just call a Kiwi "Aussie"?! #triggered #justiceforthekiwis

[@YZFoFittie]

​@izelennkhan1887 they get so pissed! LMFAO

[@MegaEpicLlama]

@@izelennkhan Aren't Richard Harris and Craig Australians?

[@zorbakaput8537]

@@MegaEpicLlama Now you're putting the slipper in LOL.

[@Ilych367]

@@MegaEpicLlamarichard harris became an aussie when we decided that his work in thailand and subsequent fame was worthy. you probably won’t get the joke but australia will claim any kiwi who gets famous enough as an aussie

[@Pnwdive]

This was an amazing slide and documentary!!! Thank you for sharing!

[@divingtalks]

It’s our mission. We promote the show and share it with the world, for those who can’t attend.

[@billstapleton1084]

At the end of the Younger Dryas, Sea levels rose over 400 ft. On our deepest dive, we can barely see what was the shoreline before the Younger Dryas.

[@JohnnyDanger36963]

At the end of and after noahs flood.

[@Secretgeek2012]

​@@JohnnyDanger36963 🙄

[@joshuapatrick682]

14:35 that group photo kind of says it all right there....

[@divingtalks]

Check out the other Talks. There were other really interesting ones. For example the the two about the underwater habitats: #DEEP by Phil Short - another highly skilled diver, and #PROTEUS by Brian Helmuth. Both worth watching.

[@markminer7390]

Kudos for pushing the boundaries and advancing diving. Fascinating talk!

[@abaDive]

Great presentation. Anything about the Pearce resurgence exploration is gold. Thank you and be safe (as much as possible :))

[@SpencerHHO]

I'm not sure if it was just the atmosphere in the room, but I feel the live audience didn't fully grasp just how incredible this actually is. I'm not a diver but I've always had a keen interest in the science and engineering involved. It's been an open secret for decades that using hydrogen would allow divers to push the envelope of dive performance. It's just very few people have had the courage to try it. I do have experience with industrial chemistry in the mining industry and manufacturing and I especially enjoyed the initial tests Harry did. As someone who's accidentally caused a small hydrogen explosion (twice) before I understand the apprehension. As humerous as the anecdote of not annoying the wife and the overall jank of that setup is, this is actually a textbook example of pushing the absolute limits of experimental and technical performance in a responsible and calaculted manner. All that helium and the low oxygen % is a really clever way to reduce the risk of turning your own lungs into an underwater bomb. It might seem crazy how easy it is to get hydrogen but you can actually access a whole load of extremely dangerous industrial reagents in Australia with virtually no hassle. You can get hydrofluoric acid, nitromethane and a bunch of precursors that you need special permits for in NA or the EU.

[@divingtalks]

This dive was an amazing achievement and everybody that attended locally was aware of that.

[@sssf55]

It's mind boggling how advance these guys are

[@r0cketplumber]

The ignition energy of H2+O2 can be as low as a few millijoules, a spark that is essentially undetectable, and easily in the range of what you can create by walking across a carpet or unrolling a few inches of cellophane tape. Scares me and I'm fearless.

[@martonlerant5672]

Well thats how the swedish inventor of hydrox died. Hydrox mixtures that ain't hypoxic at surface pressures go boom. Sure, if you are deep enough hydrox can be safe. However using it at high concentration is just an elaborate suicide.

[@chadx8269]

Agree, milli-joules from rubbing plastic tojether. The high humidity of the rebreather environment helps reduce static discharge.

[@r0cketplumber]

@@chadx8269 Also, in fairness, IF the test at one atmosphere used the at-depth trimix with 3/67/30 O2/He/H2, that is similar enough to the Tridyne 2/88/4 mix that is sometimes used for rocket tank pressurization- the O2 and H2 are too diluted by the helium to combust at all, and can only react when passed through a platinum catalyst (this makes warm gas to fill the propellant tanks as they drain). Dilution can knock out one leg of the fire triangle, but precision is mandatory. If I were doing that project, I would have done the first trimix test in open water near a shore facility with a decompression chamber instead of in the ass-end of nowhere with no hope of rescue. But then, you'd have to hold a gun on me to get me to dive in a cave- and I've jumped out of airplanes and even flew aboard a rocket plane multiple times!

[@murmenaattori6]

You forget how much inert gas the molecules are surrounded by. Nitrogen and helium.

[@pierrekinbrand]

First of all, this is amazing diving and I'm really grateful for you sharing your knowledge Dr Mitchell, and the team overall sharing their incredible adventures with us all. I know that having a wildly incorrect PPO2 in the loop is bad for plenty of other reasons, and these are really weird dives anyway for example closed curcuit bailout, extreme decompression requirement etc. But you have to admit there is just something terrifying about oxygen and hydrogen together in a compressed cylinder. Also, consider what could happen if the PPO2 increases in the loop beyond the lower flammability limit. We know already from oxygen incidents that small flakes of chrome or other contaminants being thrown through valves and first stage regulators can function as an ignition source, I just shudder at the possibility. Just off the top of my head, the introduction of H2 creates a whole class of new hazards that no one has any experience managing: - The loop that isn't being breathed can still cause problems if it's PPO2 isn't managed correctly. - PPO2 mismanagement by a buddy could cause problems for you - A blending error could result in an explosion much more energetic than simple overfilling Good luck to you guys, but I'm glad I'm not the one taking these first steps.

[@divingtalks]

Happy to share what we saw in person to the world!

[@andyprice4696]

Balls of steel on these guys. Very interesting talk.

[@divingtalks]

Thank you. Please check the other Talks, too. Many more interesting topics by other Speakers.

[@TomHlavac]

It's easier to stay alive in orbit above the atmosphere than it is doing these sorts of cave dives - there is a lot of exploring still to be done below us. I was on call for work when I watched this and am happy I did.

[@DustWolphy]

I still don't understand why they don't just use robots.

[@dwaynesykes694]

@@DustWolphy water strongly attenuates radio waves, so that won't do for command and control. Sound-based systems work in open-water, but have quite low data rates measured in characters per minute that aren't at all suitable for video or realtime control and likely wouldn't work at all inside a cave environment. That leaves tethers, which is what all underwater ROVs I'm aware of use. The tether makes supplying power and sending signals easy, but it also makes the system impractical inside a cave due to entanglement issues. I've pondered the possibility of a cave-specific ROV that has on-board power and uses an on-board spool of fiber as the tether. Having the ROV unspool its own tether as it progresses should eliminate the entanglement and sheer friction issues with having the ROV try to drag a kilometer of cable behind it. Beyond that, there's AI, but where's the fun in that. Also worth noting that some company has already made such an underwater drone. They send it off on its own and it maps the cave, then it comes back. There's no realtime information. Ultimately, some humans have always been explorers. Why go there? Because it's there.

[@chrisjames7803]

@@DustWolphy wheres the adventure then? the one thing weve done since we learnt to walk as early homonids thats EXPLORE!!

[@murmenaattori6]

​@@DustWolphy That's like saying why did we have to send people to the moon

[@wllwll-zh7ig]

​@@murmenaattori6we didn't, we only had to convince the world we did in order to maintain world power. Leadership by example. So we faked everything. Why don't you think it never happened again. Not by America or any other countries. We have no way to get through the radiation belts successfully without being killed. Government has been lying ever since. Its easier to get people to believe lies than convincing them of the truth. Government has never failed to manipulate people in crisis. Now they create crisis to manipulate people.

[@horwoodg]

My anxiety just sky rocketed the deeper you went. Amazing footage and kudos to you guys.

[@divingtalks]

Huge achievement for the group of divers portrayed in this Talk! Check out the other Talks. Many other interesting topics presented at the show and available in our channel.

[@MegaEpicLlama]

Absolute mad lads

[@carstenfrisch]

Thank you for sharing this with us, great job. It seems like we may need more explosion-proof rebreathers in the next years...

[@charlescouncill]

That’s why I don’t smoke when diving with a hydrogen mix gas.

[@killeresk]

Very interesting to watch how those kinds of dives are done. Great presentation.

[@divingtalks]

It is indeed; a great presentation about an incredible achievement. What the other Talks. Many more interesting topics!

[@SensibleCreeper]

That explosion was more than hydrogen, as we all had that high school science teacher who would ignite a balloon and hydrogen burns slow with zero shockwave... until you load it up with oxygen.

[@zdwlees]

Yh they probably did the optimum ratio 2:1

[@kelvinbarrett5917]

Simon, As always, your presentations are gold! Really interesting [boys own] science going on here.

[@divingtalks]

They are. By the way, Simon is coming to Diving Talks again this October. Join us in Lisbon. 😉👍🏼

[@AssociaçãoProjetoMergulho]

Absolutely amazing!

[@fusion2x]

Incredible work! Look forward to the paper publication on this.

[@toby1248]

'we dealt with the problems by ignoring them' True beacon of safety right here

[@divingtalks]

You have to understand that statement in the context of the presentation.

[@LoveCaveDiving]

You guys have balls. I cave dive and it is nothing not even close to what you do! Nice work!

[@YuckFoutube-e1z]

You both have a death wish.

[@stephanedolais623]

Hello everyone. I just started comercial diving training two weeks ago. Your experience sounds like a game changer. Nobody knows about it in my school. I am at Panama City. My previous career is physical conditionning. Have you heard about yoga/Pranayama/breathwork techniques to help divers prior to deep dives?

[@JB-xd9dr]

What a fascinating presentation. Thank you. I’ve no experience of anything you and your colleagues do but I have a science background, and have the utmost of respect for you. Please keep on trailblazing. One observation, why is it that there are no younger divers involved? Clearly you have vast experience. Is that it? Or is there a degree of madness too :)?

[@divingtalks]

Good point there. The ageing of diving community. That is something we should address through a serious and participated debate. But here, for the complexity of the dive, you would expect to see more experienced divers.

[@jaileal8806]

Great presentation- pioneering work. Thank you

[@OrionTheAussie]

Ill never go diving in my life i dont think. But this was still very interesting

[@RobertAgarHutton]

Wow, interesting, exciting, perhaps developing methods for the future... and.... completely and utterly bonkers !!!! :)

[@Doktracy]

Your team is awesome. I’ve followed you for years,maybe since very shortly after you first reported on Scuba Board.

[@divingtalks]

Cool. Join us this October in Lisbon. Simon is attending and presenting one more time. It will be great. 👍🏼😊

[@12pentaborane]

Everything about this is nuts, delightfully insane.

[@TheSilmarillian]

Looks like our exploration of the water filled caves below the Earth may be making leaps and bounds . Guess this will also have a float on effect to commercial deep saturation diving. Interesting times ahead indeed.

[@iaan81]

what a great talk

[@divingtalks]

And there's so much more this year! If you can't make it to Lisbon for the 4th edition of Diving Talks (18-20th October) we recommend getting the online pass to access all these great talks and debates

[@marcusthebeast2570]

Great to see people pushing boundaries, i recall ida-73 kicking on ebay few years back, was tempted to buy it, but spent all cash on boris. So looks like Russians also experimented with H2, i have one of the manual depth gauges calibrated to 300m. it would be interesting to read through some of their documents.

[@rogueFactor]

wow! there's only been a handful of these dives since 63 or something. it's an avg of about one attempt per year since hydrox was implemented. The human body is so elastic in the manner of adaptation.

[@Adrian-vd6ji]

lets not forget the human mind (real star of the show)

[@eljanrimsa5843]

@@Adrian-vd6ji you just say that just because you haven't seen what the lungs look like at those depths

[@ReefFoundation]

Keep at that science guys, as rebreather diver this is awesome

[@zachlerdahl8115]

Wow this was fascinating!

[@prycenewberg3976]

Really great presentation!

[@wilhellmllw3608]

I know nothing about diving but this looks too cool!

[@divingtalks]

It is cool. Innovative, advanced exploration, the future of diving? Enjoy the other talks, too!

[@wilhellmllw3608]

​@@divingtalks Gonna do!

[@abaDive]

Is the documentary Dr. Simon mentioned at 18:59 called Deeper? Is there any information on it like release date?

[@DrHarryH]

Yes, just announced by Screen Australia today. Hopefully will be at cinemas next year.

[@abaDive]

@@DrHarryH thank you Dr Harrison. Appreciate the reply from the man himself. That is great news, such an admirer of your work, will be awaiting eagerly. Wish you all the success.

[@Dasycottus]

The level of nerdiness here makes me joyous. As a baby tech diver, I salute you all. Stay safe, keep pushing the boundaries with your incredible science. ♥️🫧♥️

[@ian-atg]

That is lowkey malicious to say. Pushing limits in diving has historically resulted in death of those setting the new records.

[@psychosis7325]

😂 The flammability/explosiveness test was a right crack up. The old beaker in a bucket of water and bubble a SMALL amount of the mix in there then use piezo igniter from a bbq lighter would of been way to go but I don't blame him if he done half a job there deliberately, we know the margin is too close and a mistake puts you over so I'd wait till after the dive and just make a bang too.

[@AshlarPhoenix]

I cringed when i saw how much H2 was in the bag was and how close he was getting to the fire... OMG, ear-drums ringing in empathy. Ouch!

[@robertcavoli4351]

Just awesome… Thanks for the video.

[@divingtalks]

Thank you. Check the other Talks. Many more interesting topics by other Speakers.

[@daveb6345]

Wow! Truly amazing.

[@PKNEXUS]

Amazing presentation. When is N = 2 happening?

[@divingtalks]

That’s the question!! 😎

[@justgivemethetruth]

I was under the impression that H2 is pretty reactive and reacts with O2, so very surprised it would be tried in an underwater breathing mix.

[@georgewatson5197]

O2 percentages are tiny < 4% generally. The gas is only breathable at tremendous depth.

[@WineScrounger]

It does form an explosive mixture with oxygen, but it requires an ignition source to actually light off. I'm not sure what the explosive limits are under pressure.

[@georgewatson5197]

@@WineScrounger It can be ignited by adiabatic heating.

[@Kuehnert]

When we quit thinking primarily about ourselves and our own self-preservation, we undergo a truly heroic transformation of consciousness.

[@alt5494]

Truly a difficult task to solve. Would prefer building a micro submarine versus this method. The substantial volume of tanks needed plus issues with hydrogen & extreme temperature is beyond simply challenging a diver.

[@jasonturner1045]

Fascinating!!

[@JesseBusman1996]

Amazing!

[@Bomboy007]

Great talk. Thank you.

[@divingtalks]

Good to know the Talks are reaching to a wider audience!!

[@RM-en4mn]

I'm a retired licensed commercial diver - I wouldn't try this; ever. The spark risk with H2 is WAY too risky. Unless they ensure that every single metal component is constructed of brass or some other non-ignition-risk material I really think they are pushing their luck. There is research and adventure here to be sure but they appear not to have conducted sufficient risk assessment; good luck to them though as it's interesting stuff. I'll just admire from the side lines if thats OK....

[@saar144]

Does that include the tanks as well?

[@Mp57navy]

The MINIMUM amount of oxygen required to ignite hydrogen is 4%. They had 3%. That is also considering 96% hydrogen. They had 35%. Effectively, their mix was 1%.

[@ChessPampa]

Seems to be a mathematical problem, not to sound like Stockton rush

[@ChessPampa]

In the nature of chemistry

[@davidporter9131]

In a hydrogen oxygen mix, 80H2:20O2 you can smoke a cigarette.

[@gcm747]

Curiosity is an amazing driver of ingenuity.

[@divingtalks]

@@gcm747 and sometimes makes people do brilliant things. We bring those to the Diving Talks show.

[@kingmasterlord]

2:40 well, how much difference would thermoelectrics make? can your bodyheat power a peltier chip enough to warm your extremities?

[@divingtalks]

All great questions. Simon is once again coming to Lisbon for the Diving Talks October 18-20 . It's your chance to come and ask these questions to the man himself!

[@teamjenko5219]

really interesting talk!

[@bulleyes.btp1601]

It’s a great idea to replace Helium with hydrogen in Trimix gas.

[@mikeb.3918]

Wow, seriously pushing the limits. Has this cave been mapped by ROV?

[@divingtalks]

We don’t have an answer for you. Maybe someone of the team joins the discussion and clarifies.

[@frankisteve]

Ok hear me out, fully computer controlled breathing loop with all the needed gases to switch from classic trimix to the hydrogen mixture. All done automatically based on depth.

[@modernmountaineer]

Need to show the projector screen when hes talking about or describing something on it

[@heorhiypavlovych9779]

was hydrogen purified to be safe to breath at depth (to ensure it doesnt contain any toxic gases which are not a problem for other uses) ?

[@JFMNT]

I think it would be safe to assume they were purchasing the 5 9's (pure bottles of hydrogen ie 99.999%)

[@Telcomscott19]

Two many variables to go wrong for me, but of course I’m sitting on my couch!

[@connorpollard2009]

Think everyone has the same reaction watching the last vid ‘f*** hell!’😂

[@scubaclient355]

Who mixed the hydrogen and how? Why didn't RH switch to Hydrogen mix at 150?

[@ericaroland6786]

Only here looking for Gus and Woody🐙

[@joshuapatrick682]

A glimpse into a world that might as well be another dimension. I understand the science, but I am so claustrophobic that the mere thought of being underground makes me unwell. I respect the folks that can do it, but it seems purely for sport though.

[@divingtalks]

Divers are the new explorers. This group the top of those. Underwater there’s a whole new world to discover.

[@ianirwin9480]

Idk about you, but I'm a little nervous about an o2 h2 mix under pressure. Definitely wanna be Watchung you Po2 with this setup

[@saar144]

How is the PO2 relevant to this discussion? You will get the same PO2 regardless of the mix you’re using, it is only affected by the % of O2 in the mix.

[@ianirwin9480]

@@saar144 combustion calculations rely on partial pressure, if you're running a pO2 of 1 there is more than enough oxygen to cause an inferno if a fuel like hydrogen and a spark are present

[@bennyb.1742]

You crazy bastards! We talked about this for YEARS! You did it. I'm gobsmacked.

[@gadzks]

Brilliant!

[@divingtalks]

Indeed!

[@JGZimmerle]

Why didn't you test the flammability of the mixture with a cheap 30 bar pressure vessel with an electric spark generator inside? Easy enough to find a spot far from anything on some open farm land, and fill the test tank with gases remotely. Watch the whole thing from a good distance.

[@SwampCityRadio1974]

My favourite part of the video was 21:35

[@rebeccarivers4797]

Now I'm really curious how different it would be to be on Deuterium instead of Hydrogen.

[@marthinusbertusviljoen]

You guys should have nuno gomes on! Hats off to these gents, pure legends, would love to hear input from someone like nuno on the groundbreaking work these guys are doing

[@divingtalks]

Maybe we will have him soon 😉

[@marthinusbertusviljoen]

@divingtalks2566 Many thanks for the feedback! Should be really interesting, the guy was known for diving past 100m on just oxygen with ease, that coupled with him also having pushed the limits of mix diving should make for such a fun chat/discussion regarding the potential benefits of hydrogen on the nervous system at depth. Again, hats off to Richard Harris and company, takes some gargantuan nads to do what they are doing, loving the discovery of the pearse.

[@sabre22b]

As much visibility as disturbed cave silt - diagrams at the beginning?

[@mgeb101]

If temperature is a problem you can soak your wet suits in argon for a few hours before the dive or use it directly in your dry suits. Gives you quite a bit more headroom regarding temperature because of better isolation...

[@finnbismark]

Not going to get much insulation out of a wetsuit at 200+m. Even 20m compresses a wetsuit enough to substantially reduce its insulation. (Also neoprene is a closed cell structure anyway couldn’t get the argon into the neoprene after manufacturing).

[@robertfontaine3650]

Surprisingly negative posts in the thread. Experimental is experimental but there is a history of hydro hydreliox diving 500 to 700 metres. According to our friend wiki this is the 54th such experiment. With COMEX having simulated 701 metres my only question is.... When do you plan to go deeper?

[@thomasdalton1508]

Why do the testing in a cave? You could test it just as well by going to 250m in open water, surely? Wouldn't that carry much less risk? Obviously you can't just surface in an emergency, but you could have a much more substantial habitat to retreat to and you would be able to get to it much more easily.

[@misarthim6538]

In my layman eyes - the cave almost looks like better, more stable environment. 250m depth is open ocean territory, you have to deal with weather, currents, marine life, support is on a ship,...

[@thomasdalton1508]

@@misarthim6538 But you have the space to deal with all those problems.

[@keithwood6459]

I commented the same, then saw your comment. In a lake you could string everything along a cable or two from a boat. Why the expedition, helicopter, cave difficulties, remote location? Hire a boat.

[@TheKubux]

My guess is that the Hydrogen was side addon while they continued to explore the cave.

[@thomasdalton1508]

@@TheKubux It's a risky add-on, though. Why not test it in safer conditions first?

[@palehorse7377]

if im going to test an extremely dangerou gas mix 16hrs deep, Im going to also do it in a cave.

[@birddog0]

So they are going to try and go deeper eventually?

[@divingtalks]

Someone in this thread ask about it; when will we have the N=2? 😁

[@LostCylon]

Oxygen in the atmosphere is approximately 21%. Given that what they were breathing was 3%, yes it may have been flammable, but not ''explosive''.

[@duraace1000]

OMG! Diving has its risks, but we certainly don't need to add the risk of exploding when we're jumping in! 🤣

[@divingtalks]

If you want to go further and deeper you have to innovate. These are the steps and the risks taken by explorers!

[@duraace1000]

@@divingtalks Totally agree! These guys are absolutely amazing. And a great presentation! Thanks for posting!

[@Michael-iw3ek]

So what did they find in this cave that would be worth all that effort?

[@divingtalks]

The future? As before exploration leads to discovery and discovery to innovation. Yes, the future!

[@PusselButtons]

I think I remember reading a story about this…, it didn’t end well.

[@divingtalks]

Not about this dive 😉

[@DefaultProphet]

@DIVETALK pretty cool!

[@divingtalks]

@DivingTalks, not DIVETALK! Watch the other Talks. Different and interesting topics on our last event!

[@StephenCoda]

Wow. You guys have humungous nads though; Oxy hydrogen mix under pressure sounds sketch. Wonder how much humidity helps prevent unplanned exothermic events.

[@Devast8r34]

Thanks for sharing

[@morkovija]

i just hope to see self resetting scrubber one day ;)

[@stewarts9577]

Richard Harris has a video on his channel on going to depth of 245m

[@carlbroker]

You mentioned a documentary that's being made, who is making it where can I find it!? Thanks!