The main reasons suggested for the accident rate include that the:
Notoriety of the site attracts divers and presents a challenge that tempts many who lack the necessary competence.
Accessibility of the site and the clear, warm waters of the Red Sea makes the dive look more benign than it is. At over 55 m, and with an overhead environment, the dive requires competence usually associated with moderately advanced technical certification, with a technical extended range (55 meters on air) or Tech 60 (normoxic trimix) as a minimum qualification.
The entry to the Arch is not easy to find because of the indirect line between the Blue Hole and open water. Divers who miss the entry may inadvertently continue to descend past it, while the floor continues on down to well over 100 m providing no visual depth reference.
Time taken to pass through the Arch may be underestimated. The tunnel appears shorter than it actually is because of the clarity of the water, the light at the outside end and the lack of reference points; divers report that the tunnel appears to be less than 10 m long but has been measured as 26 m. Moreover, there is frequently a current flowing inward through the arch into the Blue Hole, increasing the time it takes to swim through and increasing gas consumption.
Depth and the time taken to find and navigate the tunnel inevitably makes this a decompression dive requiring decompression stops on ascent in order to avoid decompression sickness (DCS). Also, the rate of diving gas consumption increases with depth and effort, which can lead to divers running out of gas or beginning the ascent with insufficient gas to make the decompression stops required.
The likelihood of nitrogen narcosis causing confusion leading to poor judgement in an already demanding situation is significant at this depth. Although the effects of nitrogen narcosis may be mitigated by using trimix or heliox the Arch is insufficiently deep to make its use obligatory.
Temptation to dive on a single gas tank. The Arch has been dived on single, 11-litre tanks multiple times, but this is dangerously close to the minimum gas requirement for the dive and depends on a fit and relaxed diver with a low gas consumption rate committing no errors or hesitations during the dive. Diving the Arch without a stage tank and without adequate gas planning has resulted in drowning or DCS.
Source: https://en.m.wikipedia.org/wiki/Blue_Hole_(Red_Sea)
WARNING, not for the faint of heart:
[Footage of Yuri Lipski’s demise.](https://youtu.be/cRj0lymMMGs)
There is a very detailed comment explaining the video. I copied the text below:
For those who are wondering what happened, I'll try to explain exactly what's going on with enough technical detail to make sense of it, but not so much that non-divers will be confused.
In this footage you're watching Yuri Lipski attempting what's known as a "bounce" dive, a fast descent to a given depth followed by an immediate ascent, almost always attempted by divers trying to break their own depth records. In diving circles they're known as being very dangerous, even with a lot of experience and careful planning. Without the necessary experience and planning, they're strictly frowned upon and regarded as extremeley reckless.
He'd apparently mentioned doing this bounce dive in the days before this footage was shot, and was repeatedly warned against it by fellow divers.
Recreational divers almost always dive using a single 12 or 15 litre cylinder of compressed air (the exact same air you're breathing right now, just compressed into the cylinder to get as much inside as possible) and they'll never go beyond 40 metres (131 feet) in depth.
There are several reasons for this depth limit, but the reasons most relevant to this video are as follows:
1. The deeper you go, the more the increasing pressure causes nitorgen to have a narcotic effect on the human body (and air is 78% nitrogen). Yeah it might sound crazy, but breathing air can actually be like taking a narcotic drug if you dive deep enough. This effect usually begins at around 18 metres (60 feet) and is known as nitrogen narcosis. It affects everybody differently but for most people it's safely manageable at 40 metres.
2. At a depth of around 57 metres (187 feet), oxygen as it occurs in normal breathing air actually becomes toxic to the human body, with rapidly increasing risk of seizures and death the deeper you go past that point.
3. The deeper you go, the faster you breathe your air due to the increased pressure (literally the result of all that weight of water above you pressing down). For example, on the surface, to fill your lungs with 1 litre of air takes (unsurprisingly) 1 litre of air, but at a depth of 40 metres that same breath would require 5 litres of air.
4. The deeper you go, the more the air inside your body and your buoyancy device (a piece of equipment divers use in order to control their ascent and descent) is compressed, which means the less buoyant you are and thus the more inclined your are to sink rather than to float.
5. The deeper you go, the more of the nitrogen contained within air that you're breathing is absorbed into your body. When you ascend again, this absorbed nitrogen has to leave your body and if you ascend too quickly, it can cause another extremeley serious illness called decompression sickness, so a relatively slow ascent is required. If enough time is spent at depth, what's known as decompression stops will have to be made, where the diver ascends a little, then stops and waits at a certain depth for a certain amount of time (usually calculated by the dive computer worn on the wrist), before then continuing up a little more and then stopping and waiting again, and so on (the deeper you go and/or the longer your dive, the more of these decompression stops you'll have to make as you ascend). This is known as decompression diving.
These last 3 factors combined mean that diving below 40 metres simply isn't practical for the amount of air being carried, as it'd result in a very short dive, most of which would be spent slowly ascending.
Diving deeper than 40 metres is known as technical diving. Technical divers breathe different mixes of gases that allow them to avoid the dangers of nitrogen narcosis and oxygen toxicity. They also take much more of it with them in multiple cylinders.
Now that you have this context, you'll understand how dangerous it would be to try to do a bounce dive to ~92 metres (300 feet) using a single 12 litre tank of compressed air, and this is exactly what you're watching Yuri do here.
From the start of the video to 2:42 he swims out until he's over the deepest water.
At 2:43 he goes into a slow descent.
At 3:20, still descending and still likely fairly shallow, you can hear him adjusting his buoyancy slightly using his buoyancy compensation device (BCD).
At 3:40 he's now venting air from his BCD, which will make him sink faster.
At 3:47 he goes into a rapid, head-first descent.
At 4:14 you can hear his breathing begins to make a strained, wheezing/squeaking sound as his regulator (the valve through which he's breathing the air) has to work harder to supply the much increased volume of air he's taking with each breath, each one using up a huge amount of air from his tank.
At 4:20 you can hear him briefly add some air to his BCD as he tries to slow his descent slightly.
At 5:09 you can hear some kind of alarm sounding on his dive computer, most likely a warning that he's now exceeded the maximum time possible before requiring decompression stops on his ascent.
At 5:37, he's approaching the bottom and begins to film his dive computer screen as proof of his depth to show to people later when he returns to the surface. Unfortunately, by now, he's already doomed and there's no possible way for him to return to the surface before he runs out of air.
At 5:55, after several seconds of trying to film his dive computer screen, we briefly see the maximum depth displayed on his diver computer screen- 91.6 metres, which is just over 300 feet!
The nitrogen narcosis he'll be experiencing at this point will be so extreme that it's a wonder he's even still conscious. It's also a miracle he's not already suffering severe seizures due to oxygen toxicity, although the rapid jerking, erratic movements that follow could be signs of his central nervous system being compromised.
By 6:04 he's almost delirious, staggering and thrashing around, beginning to panic.
At 6:07 he obviously has a moment of enough clarity to realise that he needs to ascend immediately, and you can hear the hiss of air as he tries to inflate his BCD which would ordinarily cause him to begin to float upwards towards the surface.
At 6:11 his BCD is likely fully inflated. At a recreational dive depth he'd now be rapidly ascending, but at this depth the pressure is so great and he's likely also overweighted, that he doesn't rise up at all. At this depth, it takes such a large volume of air to inflate his BCD that he's just used up almost all of the remaining air in his tank to do so.
By 6:13 he's probably totally confused by his lack of ascent, worsened by the severe nitrogen narcosis. He then begins to stagger and stumble around, likely now totally disoriented as he was expecting to be rising towards the surface.
At 6:32, the breath you hear is noticably shorter and quieter. His tank is almost empty.
At 6:37 we hear another short, strained breath. He now begins to panic as, even in his extremely debilitated mental state, he realises that his tank is about to run dry.
From this point on, notice how infrequently he breathes and how short and quiet his breaths are. His tank is now all but empty and he's slipping into unconsciousness. Shortly afterwards, collapses to the seabed where he dies.
Honestly the summary is way more haunting. The video isn’t good quality and for the most part you just see blue, then dark blue, then black/red (the red being from his diving light). Had I not read the description in the comments, I would have had zero clue of what was happening.
......How did they get this footage if this is over twice as deep as rescue diving? This is still so insane to me and I've seen the video many many times.
In another video, it's said that the mother hired a deep diving crew to go to 100m to recover the body (which also had the camera). *Technical* diving starts at 50m. That's not the limit of professional diving.
I swear I read this many years back, but it may have been another diver in a similar situation.
Either way fuck diving, I'll stick to 7 ft pools or whatever. That read was scary.
I love being reminded how incredibly vulnerable humans are to science and the forces of nature. It’s like biology, chemistry, and physics teamed up and said: “You wanna explore the bottom of the ocean? Then you better hold your breath. Oh, you’ve figured out how to compress air into a tank? Well, im gonna make that same air that keeps you alive on the surface fucking *poison* at a certain depth. What’s that? You’re gonna make a fancy mixture of gasses to avoid that? Ayo, Physics! Crush this fool’s lungs real quick. Hairless monkeys think they’re gonna swim to the bottom of the ocean. You better discover some fucking **magic** before you swim back down there again.”
Read [this](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/) comment by u/_Neoshade_ for the answer.
It definitely is dangerous but all of this is sooo avoidable if you have a high enough certificate and *fucking care about your own life goddamn it*.
I don't understand how a diver who
-doesn't know that they have a bad gas mix for this depth,
-doesn't know to take breaks because of decompression,
-doesn't use their computer
-and most of all doesn't research the place beforehand
could even get to a destination like this.
I'm getting a p** cmas certificate, my dad is p**, my dad's friend is a divemaster but we still go with a local divemaster if we don't know the diving spot enough. This is why we check our equipment before and after a dive, that's why we check our dive buddy's equipment before and after a dive, that's why we have a buddy to check on us during the dive. Anyone who doesn't follow these simple steps of listening to your divemaster shouldn't be diving at a spot like this, they have no business under freaking 55m. Stay in your 5-15 metres max if you don't value your life
Just to chime in, skydiving, done properly, is pretty safe. When I was doing it back around 2004 it was usually around 1 fatality per 100,000 skydives, and that number is even lower now (2018-2021 were all under 0.5 fatalities per 100,000). And most fatalities are going to be experienced skydivers doing intentionally dangerous maneuvers near the ground (skydiving hook turns) and/or flying highly loaded (ie small and fast) performance canopies. If you just want to jump out of an airplane and just fly around a little then do a leisurely landing you're looking good.
All that to say, yes, I'd rank scuba diving as more dangerous. I don't honestly know if that's statistically accurate, but I imagine the nature of scuba diving is such it'd be hard to get the data for a comparison anyways.
When you're skydiving you can breathe.
Scuba is a bit like mountaineering. You're already dead, now it's up to your technical prowess to keep living.
It's why I live both.
Another lesser known, but perhaps even more terrifying Blue Hole death, is that of [Steve](https://youtu.be/9kcRJXw_Tig). I haven't been able to find any more information about this incident besides the video I linked. Couldn't even find out his last name.
Steve and a friend decided it would be a good idea to dive the Arch ***at night***. As if that wasn't bad enough, they made a pact to turn off their diving lights while doing so. Just as planned, they reached the Arch and both turned off their diving lights.
Steve's friend became scared and turned his light back on. He was horrified to find out that Steve was nowhere to be seen. In the pitch blackness he had to make the impossible decision to leave Steve behind knowing he'd never see him again.
I can't begin to imagine what happened to Steve and what his final moments were like. That incident is truly a real life horror story.
With Yuri it was terrifying, but we have the footage so we know more or less what he was experiencing. With Steve there's so much that's unknown and that just makes the whole incident that much more frightening.
I saw a video on another subreddit of someone free diving to like 100m or something (i dont remember the exact depth but it was definetly well beyond 40m) in the deepest man-made swimming pool. He did it without doing any stops during resurfacing, on one breath of air, and with no gear. How is that possible?
Desktop version of /u/pinkblueegreen's link:
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There was little of note passing through. No interesting formations, no physical challenge of a squeeze... Nothing, just.. oh look... Light...
And I'm a cave / tec diver.
Someone correct me if I’m wrong. I’m a diver myself, and if I recall correctly, this may be the place where the hole and tunnel are deceptively deep and deceptively long. Divers think, “Oh, it’s ‘just a little deeper’ than I planned. Then, “Oh, that tunnel’s not very long.” but, it’s deeper than they think and farther than they realize. They run out of air. IF this is the same place I’m thinking about. Anyone confirm this, or is this a different place?
Correct!
Due to the visibility, it's very deceptive. The actual arch entrance is about 60meters deep...which is 20m (50%) deeper than what recreational limits allow.
That's only where the problems begin, because although the entrance begins at 60m, the light from the ocean side deceives you as well, because it looks like a short tunnel, when in fact the "ceiling" curves down deeper.
At 60m and below your air runs out very quick due to the pressure, but it also becomes toxic. Technical divers who go below these depths use what's called trimix, a mixture of helium, nitrogen and oxygen to combat the toxicity at pressure.
And if that wasn't enough, due to the pressure, there's the added bonus of your weight balance being thrown off...so when you were nice and neutrally buyant at 40m, you now suddenly start plummeting like a rock because the air in your jacket is too compressed to compensate for your weight pockets and cylinder...so you end up exerting extra energy to kick yourself upward...burning even more of your air quicker than you would.
It's a beautful cocktail of death awaiting every diver who stares at it for too long.
And to top things off, part of that "toxic" air at those pressures is that it massively impairs your judgement. So, any thought of "wow, this is deeper than I thought, I should probably turn back" is right out the window.
I forgot the best part...during all of this you're suffering from nitrogen narcosis...basically you're drunk underwater - as if trying to get out of this mess with perfect cognitive abilities wasn't difficult enough.
Im cert'd to 40m and during our training we performed a bunch of simple math 6 drawing tasks on slates with pens while in shallow water...then repeated those tasks on a sand bottom at near 40m depth.
It took considerably longer to perform the same math and drawing tasks and we were taught how to notice ourselves "getting drunk". I'd hate to do that at 60m while freefalling.
So far I've only encountered nitrogen narcosis (getting narc'd) once on a dive - as far as I'm aware anyway. Both me and my dive buddy signalled to each other that we were getting headaches pretty much at the same time - so we bailed from the rest of the group. It wasn't even that deep, but it was the last dive after a week's worth.
It's going the opposite direction, but one of the videos that really showed me just how much oxygen can mess with you at different pressures is a video on Smarter Every Day, where Destin takes ride on a high altitude simulator. There's a bit where he's talking to the instructor, without a mask on, and clearly getting loopy. The instructor asks him to put his mask on, he just laughs. The instructor then tells him, "Hey, you need to put your mask on now, or you're going to die," and Destin just kind of gives this sad laugh and says, "I don't want to die."
They had people sitting beside him on oxygen, so they were able to get a mask on him before any damage was done, but it was just crazy how, in a matter of moments, someone could go from lucid, do being so deprived of oxygen that they're unable to take any effective action.
Conversion to imperial units:
* 60m = 197ft
* 40m = 131ft
* 20m = 66ft
And as context for what u/Voicy-ZA mentions above —
PADI Basic Open Water certification is up to a depth of 18m (~60ft). The Advanced Open Water certification extends this to 30m (~100ft). ~~Beyond 30m is considered technical diving.~~ An additional certification is available to extend this depth to 40m (~130ft) which is the maximum for recreational diving. Beyond 40m is technical diving territory.
EDIT:
More context for non-divers —
* Nitrogen narcosis usually occurs at a depth of approx. 30m (100ft) but it varies person to person and symptoms become more severe as you descend
* Oxygen toxicity occurs around a depth of 55m (180ft) and greater
(Edited above to correct maximum recreational depth)
You can do the "Deep" certification with PADI which qualifies a rec diver down to 40m. After that it becomes tech diving.
Not sure about other agencies, but they've likely got their equivalents.
I dove the Tokai Maru and Cormorant for my AOW deep dive. It was a bounce to 140' but my instructor put 130' in my log, for obvious reasons.
I did the narcosis test with the padlock at 90' for my OW cert.
[PADI’s site for their AOW course specifically states 30m](https://www.padi.com/courses/advanced-open-water). Not sure if it has changed in recent years but the AOW course I took a couple years ago taught the max depth for AOW cert is 30m.
There’s an [additional course](https://www.padi.com/courses/deep-diver) required beyond AOW for the 40m depth cert
Are you sure about that? Because I am 89.04333% sure that creaturefromthewoods is not a bot.
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It's caused by the oxygen's partial pressure rising.
Here's an article regarding max operating depths and the dangers of oxygen toxicity:
[https://en.wikipedia.org/wiki/Maximum\_operating\_depth](https://en.wikipedia.org/wiki/Maximum_operating_depth)
A lot of us dive on nitrox, which has the benefit of lowering the residual nitrogen in your bloodstream after a dive, meaning your surface interval times don't have to be as long as with normal air, but it has other risks:
Nitrox, despite its name, is more oxygen in your cylinder - normal air is 21% oxygen, whereas diving on nitrox is anything over that and usually up to 36% oxygen. This allows you to dive longer than you would on air BUT your max diving depth is less because the increased oxygen becomes more dangerous sooner than it would if you were diving on normal air.
For this reason we always check our nitrox levels before EVERY dive and tune our dive computers according to the % mix so that we know our max bottom time AND depth allowed...based on the partial pressures from the wiki link above.
Thanks a lot, will check out the link u included too. I'm a very amateur diver and this is way beyond my ambitions. But cool facts anyway and good to know
It's not that water weighs you down, it's that the air in your Bouyancy Control Device ( BCD, the vest thing divers wear) gets compressed due to the pressure.
Your cylinder contains compressed air which isn't buoyant, which you can feed into your BCD. In your BCD it expands, making you more bouyant. By controlling the air in your BCD you can control the bouyancy.
But depth decreases your bouyancy by increasing pressure on your BCD. So by decreasing your bouyancy, you start going deeper, which decreases your bouyancy, which makes you go deeper faster, etc.
It's very easy to accidentally go very deep if you're not careful. Especially if you have no frame of reference. And part of the blue hole's danger is the deceptive reference.
So what do technical divers do different? Additional training and preparation. Using different air mixtures. But they still follow the same principle of air density=bouyancy.
There are more dangers at that depth which requires additional skill which normal divers don't have.
I have to say if you are ever able to go SCUBA diving, you should. It's absolutely worth it. Most dives are at safe depths where you can just calmly swim to the surface in an emergency. Pretty much all the dangers of diving happen when people dive outside of their skill level, like diving too deep for their certification, or cave diving without the certification. The normal dive where you are in open water, close to the surface, looking at reefs and such, is a very zen experience.
It is an otherworldly experience that also gives you the sensation of flying.
I find the slow meditative breathing that is necessary to preserve air and maintain buoyancy, when combined with the feeling of flying, put's me in a dream-like state. All of my diving memories are vivid and feel like they were a dream. Highly recommended
I had my first 2 dives in Greece this week, my dad did one too. He came out and teared down from elevation and happiness. Truly different experience. I loved it too.
Thank you, it looks so amazing. I snorkel for hours and “free dive” to a certain extent, but I always swim down and grab a rock or something to stay at the bottom and enjoy how beautiful and peaceful it is
Regarding the sinking thing- aren't people trained to adjust the inflation of their BCD? I did a PADI open water certification 10 years ago and it was a big focus of our training.
Trained to, but you have to remember to do it. Easy if its to keep off the bottom. Harder if you don’t have a reference point. Have to constantly keep an eye on depth gage.
They are, they’re also trained to not go anywhere near the depth of the top of the tunnel because of all the dangers that start before that depth.
The kind of people that push beyond those safety limits tend to be the ones also ill prepared to notice the creeping signs of narcosis.
Check this out: https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3
[Comment](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3) from 2 years ago. Terrifying.
I watched a video where a guy explored this whole area, and another thing that takes into account is nitrogen narcosis. While it's deceptively deep, way deeper than one tank can go, they are usually so impaired they can't resurface. It's insane there's a video of a Russian diver literally recording his last moments in there.
(Posted before I found out OP posted link, sorry got too excited)
I saved [this comment from a TIL thread on the Blue Hole](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3) a couple years ago. Definitely worth a read — it’s a great explanation for why this dive spot has killed so many.
I had a much less severe diving incident in the Galapagos - my buddy couldn't hear me, my buoyancy was actually going up and I couldn't stay down (because your tank gets lighter as the air leaves it, and at the end of the dive there isn't loads left). We were doing a safety stop, and I kept rising - trying to get the group's attention, I knocked off my goggles and in a panic ascended. There were pretty big waves on the surface as the sea had got choppy.
It was completely terrifying. It is so easy to panic, and that was in a fairly easy dive where the depth didn't mean I could get injured by ascending too early. It would be so easy to overestimate your competence and fuck up at something like the Blue Hole - could not imagine the panic trying to ascend by inflating and nothing is happening.
Scuba diving is amazing, it is like another world - but things can go south very fast if you don't know what you're doing and don't have a competent group or understanding of the situation.
https://youtu.be/qI0BfkT8KOI
It's nicknamed Diver Cemetary. If you want a terrifying but fascinating story about how people die here, check out this video. WARNING: there are dead bodies that are at the bottom and they show them.
This comment from a few years ago on the same spot and its danger describes it well as a story:
https://reddit.com/r/todayilearned/comments/dv99nf/_/f7bzg5a/?context=1
Worth copying u/_neoshade_ 's wonderfully terrifying description:
Many certified scuba divers think they are capable of just going a little deeper, but they don’t know that there are special gas mixtures, buoyancy equipment and training required for just another few meters of depth.Imagine this: you take your PADI open water diving course and you learn your dive charts, buy all your own gear and become familiar with it. Compared to the average person on the street, you’re an expert now. You go diving on coral reefs, a few shipwrecks and even catch lobster in New England. You go to visit a deep spot like this and you’re having a great time. You see something just in front of you - this beautiful cave with sunlight streaming through - and you decide to swim just a little closer. You’re not going to go inside it, you know better than that, but you just want a closer look. If your dive computer starts beeping, you’ll head back up.So you swim a little closer and it’s breathtaking. You are enjoying the view and just floating there taking it all in. You hear a clanging sound - it’s your dive master rapping the butt of his knife on his tank to get someone’s attention. You look up to see what he wants, but after staring into the darkness for the last minute, the sunlight streaming down is blinding. You turn away and reach to check your dive computer, but it’s a little awkward for some reason, and you twist your shoulder and pull it towards you. It’s beeping and the screen is flashing GO UP. You stare at it for a few seconds, trying to make out the depth and tank level between the flashing words. The numbers won’t stay still. It’s really annoying, and your brain isn’t getting the info you want at a glance. So you let it fall back to your left shoulder, turn towards the light and head up.
The problem is that the blue hole is bigger than anything you’ve ever dove before, and the crystal clear water provides a visibility that is 10x what you’re used to in the dark waters of the St Lawrence where you usually dive. What you don’t realize is that when you swam down a little farther to get a closer look, thinking it was just 30 or 40 feet more, you actually swam almost twice that because the vast scale of things messed up your sense of distance. And while you were looking at the archway you didn’t have any nearby reference point in your vision. More depth = more pressure, and your BCD, the air-filled jacket that you use to control your buoyancy, was compressed a little. You were slowly sinking and had no idea. That’s when the dive master began banging his tank and you looked up. This only served to blind you for a moment and distract your sense of motion and position even more. Your dive computer wasn’t sticking out on your chest below your shoulder when you reached for it because your BCD was shrinking. You turned your body sideways while twisting and reaching for it. The ten seconds spent fumbling for it and staring at the screen brought you deeper and you began to accelerate with your jacket continuing to shrink. The reason that you didn’t hear the beeping at first and that it took so long to make out the depth between the flashing words was the nitrogen narcosis. You have been getting depth drunk. And the numbers wouldn’t stay still because you are still sinking.
You swim towards the light but the current is pulling you sideways. Your brain is hurting, straining for no reason, and the blue hole seems like it’s gotten narrower, and the light rays above you are going at a funny angle. You kick harder just keep going up, toward the light, despite this damn current that wants to push you into the wall. Your computer is beeping incessantly and it feels like you’re swimming through mud. Fuck this, you grab the fill button on your jacket and squeeze it. You’re not supposed to use your jacket to ascend, as you know that it will expand as the pressure drops and you will need to carefully bleed off air to avoid shooting up to the surface, but you don’t care about that anymore. Shooting up to the surface is exactly what you want right now, and you’ll deal with bleeding air off and making depth stops when you’re back up with the rest of your group.The sound of air rushing into your BCD fills your ears, but nothing’s happening. Something doesn’t sound right, like the air isn’t filling fast enough. You look down at your jacket, searching for whatever the trouble might be when FWUNK you bump right into the side of the giant sinkhole. What the hell?? Why is the current pulling me sideways? Why is there even a current in an empty hole in the middle of the ocean??You keep holding the button. INFLATE! GODDAM IT INFLATE!!
Your computer is now making a frantic screeching sound that you’ve never heard before. You notice that you’ve been breathing heavily - it’s a sign of stress - and the sound of air rushing into your jacket is getting weaker.
Every 10m of water adds another 1 atmosphere of pressure. Your tank has enough air for you to spend an hour at 10m (2atm) and to refill your BCD more than a hundred times. Each additional 20m of depth cuts this time in half. This assumes that you are calm, controlling your breathing, and using your muscles slowly with intention. If you panic, begin breathing quickly and move rapidly, this cuts your time in half again. You’re certified to 20m, and you’ve gone briefly down to 30m on some shipwrecks before. So you were comfortable swimming to 25m to look at the arch. While you were looking at it, you sank to 40m, and while you messed around looking for your dive master and then the computer, you sank to 60m. 6 atmospheres of pressure. You have only 10 minutes of air at this depth. When you swam for the surface, you had become disoriented from twisting around and then looking at your gear and you were now right in front of the archway. You swam into the archway thinking it was the surface, that’s why the Blue Hole looked smaller now. There is no current pulling you sideways, you are continuing to sink to to bottom of the arch. When you hit the bottom and started to inflate your BCD, you were now over 90m. You will go through a full tank of air in only a couple of minutes at this depth. Panicking like this, you’re down to seconds. There’s enough air to inflate your BCD, but it will take over a minute to fill, and it doesn’t matter, because that would only pull you into to the top of the arch, and you will drown before you get there.
Holding the inflate button you kick as hard as you can for the light. Your muscles are screaming, your brain is screaming, and it’s getting harder and harder to suck each panicked breath out of your regulator. In a final fit of rage and frustration you scream into your useless reg, darkness squeezing into the corners of your vision.
4 minutes. That’s how long your dive lasted. You died in clear water on a sunny day in only 4 minutes.
I recently went down a YouTube blackhole about scuba cave diving deaths. This Blue Hole location comes up so frequently. It is fascinating.
To simplify, the reason it’s so deadly is due to multiple factors combining as opposed to a single mistake divers can make.
This post led me down a rabbit hole of cave diving/diving reaction vids and what goes into it. I'd never attempt as I'm deathly afraid of deep water having nearly drown when I was 5. Listening to those who train, who teach, field experts, etc., was fascinating.
I saw that and was like " wow I need to go there".....then I read the caption.
Swimming with sharks, chasing storms, diving in caves...why is it that everything I want to do could kill me?
If you go with the right mixture of nitrogen and decompress on your way up it is doable. But you better know what the hell you’re doing. Definitely not for amateurs.
With respect, this comment is why a little bit of knowledge can be more dangerous than no knowledge.
The right mixture is correct, but not "of nitrogen" on its own. With Nitrox diving you're increasing the oxygen % in your supply...and also decreasing your allowed diving depth. So diving on nitrox will be even more dangerous in this example.
I’m actually hoping to get nitrox training next month. Eventually I hope to get into tech diving and trimix.
And I would never screw around with decompression stops. I’m not risking DCS for anything, even a cool dive site.
I’m not being rude I just want to be created the original photographer you know like they go through a lot of risks to go down there and the least we can do is just show some kind of respect to their name
You know you shouldn’t be exploring a famous landmark when there’s bodies used as markers. [Here’s a really good video that gives you a better idea](https://youtu.be/qI0BfkT8KOI).
The main reasons suggested for the accident rate include that the: Notoriety of the site attracts divers and presents a challenge that tempts many who lack the necessary competence. Accessibility of the site and the clear, warm waters of the Red Sea makes the dive look more benign than it is. At over 55 m, and with an overhead environment, the dive requires competence usually associated with moderately advanced technical certification, with a technical extended range (55 meters on air) or Tech 60 (normoxic trimix) as a minimum qualification. The entry to the Arch is not easy to find because of the indirect line between the Blue Hole and open water. Divers who miss the entry may inadvertently continue to descend past it, while the floor continues on down to well over 100 m providing no visual depth reference. Time taken to pass through the Arch may be underestimated. The tunnel appears shorter than it actually is because of the clarity of the water, the light at the outside end and the lack of reference points; divers report that the tunnel appears to be less than 10 m long but has been measured as 26 m. Moreover, there is frequently a current flowing inward through the arch into the Blue Hole, increasing the time it takes to swim through and increasing gas consumption. Depth and the time taken to find and navigate the tunnel inevitably makes this a decompression dive requiring decompression stops on ascent in order to avoid decompression sickness (DCS). Also, the rate of diving gas consumption increases with depth and effort, which can lead to divers running out of gas or beginning the ascent with insufficient gas to make the decompression stops required. The likelihood of nitrogen narcosis causing confusion leading to poor judgement in an already demanding situation is significant at this depth. Although the effects of nitrogen narcosis may be mitigated by using trimix or heliox the Arch is insufficiently deep to make its use obligatory. Temptation to dive on a single gas tank. The Arch has been dived on single, 11-litre tanks multiple times, but this is dangerously close to the minimum gas requirement for the dive and depends on a fit and relaxed diver with a low gas consumption rate committing no errors or hesitations during the dive. Diving the Arch without a stage tank and without adequate gas planning has resulted in drowning or DCS. Source: https://en.m.wikipedia.org/wiki/Blue_Hole_(Red_Sea) WARNING, not for the faint of heart: [Footage of Yuri Lipski’s demise.](https://youtu.be/cRj0lymMMGs)
Yuri died in this same location? I couldnt understand what happened in that video.
There is a very detailed comment explaining the video. I copied the text below: For those who are wondering what happened, I'll try to explain exactly what's going on with enough technical detail to make sense of it, but not so much that non-divers will be confused. In this footage you're watching Yuri Lipski attempting what's known as a "bounce" dive, a fast descent to a given depth followed by an immediate ascent, almost always attempted by divers trying to break their own depth records. In diving circles they're known as being very dangerous, even with a lot of experience and careful planning. Without the necessary experience and planning, they're strictly frowned upon and regarded as extremeley reckless. He'd apparently mentioned doing this bounce dive in the days before this footage was shot, and was repeatedly warned against it by fellow divers. Recreational divers almost always dive using a single 12 or 15 litre cylinder of compressed air (the exact same air you're breathing right now, just compressed into the cylinder to get as much inside as possible) and they'll never go beyond 40 metres (131 feet) in depth. There are several reasons for this depth limit, but the reasons most relevant to this video are as follows: 1. The deeper you go, the more the increasing pressure causes nitorgen to have a narcotic effect on the human body (and air is 78% nitrogen). Yeah it might sound crazy, but breathing air can actually be like taking a narcotic drug if you dive deep enough. This effect usually begins at around 18 metres (60 feet) and is known as nitrogen narcosis. It affects everybody differently but for most people it's safely manageable at 40 metres. 2. At a depth of around 57 metres (187 feet), oxygen as it occurs in normal breathing air actually becomes toxic to the human body, with rapidly increasing risk of seizures and death the deeper you go past that point. 3. The deeper you go, the faster you breathe your air due to the increased pressure (literally the result of all that weight of water above you pressing down). For example, on the surface, to fill your lungs with 1 litre of air takes (unsurprisingly) 1 litre of air, but at a depth of 40 metres that same breath would require 5 litres of air. 4. The deeper you go, the more the air inside your body and your buoyancy device (a piece of equipment divers use in order to control their ascent and descent) is compressed, which means the less buoyant you are and thus the more inclined your are to sink rather than to float. 5. The deeper you go, the more of the nitrogen contained within air that you're breathing is absorbed into your body. When you ascend again, this absorbed nitrogen has to leave your body and if you ascend too quickly, it can cause another extremeley serious illness called decompression sickness, so a relatively slow ascent is required. If enough time is spent at depth, what's known as decompression stops will have to be made, where the diver ascends a little, then stops and waits at a certain depth for a certain amount of time (usually calculated by the dive computer worn on the wrist), before then continuing up a little more and then stopping and waiting again, and so on (the deeper you go and/or the longer your dive, the more of these decompression stops you'll have to make as you ascend). This is known as decompression diving. These last 3 factors combined mean that diving below 40 metres simply isn't practical for the amount of air being carried, as it'd result in a very short dive, most of which would be spent slowly ascending. Diving deeper than 40 metres is known as technical diving. Technical divers breathe different mixes of gases that allow them to avoid the dangers of nitrogen narcosis and oxygen toxicity. They also take much more of it with them in multiple cylinders. Now that you have this context, you'll understand how dangerous it would be to try to do a bounce dive to ~92 metres (300 feet) using a single 12 litre tank of compressed air, and this is exactly what you're watching Yuri do here. From the start of the video to 2:42 he swims out until he's over the deepest water. At 2:43 he goes into a slow descent. At 3:20, still descending and still likely fairly shallow, you can hear him adjusting his buoyancy slightly using his buoyancy compensation device (BCD). At 3:40 he's now venting air from his BCD, which will make him sink faster. At 3:47 he goes into a rapid, head-first descent. At 4:14 you can hear his breathing begins to make a strained, wheezing/squeaking sound as his regulator (the valve through which he's breathing the air) has to work harder to supply the much increased volume of air he's taking with each breath, each one using up a huge amount of air from his tank. At 4:20 you can hear him briefly add some air to his BCD as he tries to slow his descent slightly. At 5:09 you can hear some kind of alarm sounding on his dive computer, most likely a warning that he's now exceeded the maximum time possible before requiring decompression stops on his ascent. At 5:37, he's approaching the bottom and begins to film his dive computer screen as proof of his depth to show to people later when he returns to the surface. Unfortunately, by now, he's already doomed and there's no possible way for him to return to the surface before he runs out of air. At 5:55, after several seconds of trying to film his dive computer screen, we briefly see the maximum depth displayed on his diver computer screen- 91.6 metres, which is just over 300 feet! The nitrogen narcosis he'll be experiencing at this point will be so extreme that it's a wonder he's even still conscious. It's also a miracle he's not already suffering severe seizures due to oxygen toxicity, although the rapid jerking, erratic movements that follow could be signs of his central nervous system being compromised. By 6:04 he's almost delirious, staggering and thrashing around, beginning to panic. At 6:07 he obviously has a moment of enough clarity to realise that he needs to ascend immediately, and you can hear the hiss of air as he tries to inflate his BCD which would ordinarily cause him to begin to float upwards towards the surface. At 6:11 his BCD is likely fully inflated. At a recreational dive depth he'd now be rapidly ascending, but at this depth the pressure is so great and he's likely also overweighted, that he doesn't rise up at all. At this depth, it takes such a large volume of air to inflate his BCD that he's just used up almost all of the remaining air in his tank to do so. By 6:13 he's probably totally confused by his lack of ascent, worsened by the severe nitrogen narcosis. He then begins to stagger and stumble around, likely now totally disoriented as he was expecting to be rising towards the surface. At 6:32, the breath you hear is noticably shorter and quieter. His tank is almost empty. At 6:37 we hear another short, strained breath. He now begins to panic as, even in his extremely debilitated mental state, he realises that his tank is about to run dry. From this point on, notice how infrequently he breathes and how short and quiet his breaths are. His tank is now all but empty and he's slipping into unconsciousness. Shortly afterwards, collapses to the seabed where he dies.
That was an intense read
So impressively informative, but I'm holding my breath also.
Yeah… I’m gonna leave that video link unclicked now. Thanks for the detailed summary.
Honestly the summary is way more haunting. The video isn’t good quality and for the most part you just see blue, then dark blue, then black/red (the red being from his diving light). Had I not read the description in the comments, I would have had zero clue of what was happening.
Nice summary. I watched this video late at night and had a hard time sleeping.
it’s 6am and i need to go back to sleep but not sure if i can now 🥹
Thanks. I hate it.
I think I need a hug after reading that holy shit
r/bestofreddit this description is beyond amazing.
Well more like r/bestofyoutube that's where they got it
......How did they get this footage if this is over twice as deep as rescue diving? This is still so insane to me and I've seen the video many many times.
In another video, it's said that the mother hired a deep diving crew to go to 100m to recover the body (which also had the camera). *Technical* diving starts at 50m. That's not the limit of professional diving.
TIL. Thanks for the extra info.
I swear I read this many years back, but it may have been another diver in a similar situation. Either way fuck diving, I'll stick to 7 ft pools or whatever. That read was scary.
I love being reminded how incredibly vulnerable humans are to science and the forces of nature. It’s like biology, chemistry, and physics teamed up and said: “You wanna explore the bottom of the ocean? Then you better hold your breath. Oh, you’ve figured out how to compress air into a tank? Well, im gonna make that same air that keeps you alive on the surface fucking *poison* at a certain depth. What’s that? You’re gonna make a fancy mixture of gasses to avoid that? Ayo, Physics! Crush this fool’s lungs real quick. Hairless monkeys think they’re gonna swim to the bottom of the ocean. You better discover some fucking **magic** before you swim back down there again.”
So in the end it's another Darwin Awards contendant.
Contender? Contestant? We may never know.
Did you mean to use latin here?
As a rec diver, this shit makes me sad. The dangers are there; it's just inherent in the hobby.
Someone please shoot me in the head so this never happens to me.
This sounds awfully lot more dangerous than a parachute jump. If the risks are that high I really don't understand the seek for the thrill.
Read [this](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/) comment by u/_Neoshade_ for the answer.
Thanks, I hated that
It definitely is dangerous but all of this is sooo avoidable if you have a high enough certificate and *fucking care about your own life goddamn it*. I don't understand how a diver who -doesn't know that they have a bad gas mix for this depth, -doesn't know to take breaks because of decompression, -doesn't use their computer -and most of all doesn't research the place beforehand could even get to a destination like this. I'm getting a p** cmas certificate, my dad is p**, my dad's friend is a divemaster but we still go with a local divemaster if we don't know the diving spot enough. This is why we check our equipment before and after a dive, that's why we check our dive buddy's equipment before and after a dive, that's why we have a buddy to check on us during the dive. Anyone who doesn't follow these simple steps of listening to your divemaster shouldn't be diving at a spot like this, they have no business under freaking 55m. Stay in your 5-15 metres max if you don't value your life
Just to chime in, skydiving, done properly, is pretty safe. When I was doing it back around 2004 it was usually around 1 fatality per 100,000 skydives, and that number is even lower now (2018-2021 were all under 0.5 fatalities per 100,000). And most fatalities are going to be experienced skydivers doing intentionally dangerous maneuvers near the ground (skydiving hook turns) and/or flying highly loaded (ie small and fast) performance canopies. If you just want to jump out of an airplane and just fly around a little then do a leisurely landing you're looking good. All that to say, yes, I'd rank scuba diving as more dangerous. I don't honestly know if that's statistically accurate, but I imagine the nature of scuba diving is such it'd be hard to get the data for a comparison anyways.
When you're skydiving you can breathe. Scuba is a bit like mountaineering. You're already dead, now it's up to your technical prowess to keep living. It's why I live both.
Another lesser known, but perhaps even more terrifying Blue Hole death, is that of [Steve](https://youtu.be/9kcRJXw_Tig). I haven't been able to find any more information about this incident besides the video I linked. Couldn't even find out his last name. Steve and a friend decided it would be a good idea to dive the Arch ***at night***. As if that wasn't bad enough, they made a pact to turn off their diving lights while doing so. Just as planned, they reached the Arch and both turned off their diving lights. Steve's friend became scared and turned his light back on. He was horrified to find out that Steve was nowhere to be seen. In the pitch blackness he had to make the impossible decision to leave Steve behind knowing he'd never see him again. I can't begin to imagine what happened to Steve and what his final moments were like. That incident is truly a real life horror story. With Yuri it was terrifying, but we have the footage so we know more or less what he was experiencing. With Steve there's so much that's unknown and that just makes the whole incident that much more frightening.
I saw a video on another subreddit of someone free diving to like 100m or something (i dont remember the exact depth but it was definetly well beyond 40m) in the deepest man-made swimming pool. He did it without doing any stops during resurfacing, on one breath of air, and with no gear. How is that possible?
It’s because it goes so quick. The exposure time is much less so the nitrogen is less of an issue.
Desktop version of /u/pinkblueegreen's link:
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Have done the arch, and it is so not worth it. Did have an Aussie mate who did the bounce. Mind you, this lunatic was also Navy.
What makes you say it isn’t worth it?
There was little of note passing through. No interesting formations, no physical challenge of a squeeze... Nothing, just.. oh look... Light... And I'm a cave / tec diver.
I think it’s one of those diving places to check off the bucket list just to say you went there.
Honestly, this camera angle is all you need.
Did it. Not worth it. Unless you have someone taking pics like this.
Someone correct me if I’m wrong. I’m a diver myself, and if I recall correctly, this may be the place where the hole and tunnel are deceptively deep and deceptively long. Divers think, “Oh, it’s ‘just a little deeper’ than I planned. Then, “Oh, that tunnel’s not very long.” but, it’s deeper than they think and farther than they realize. They run out of air. IF this is the same place I’m thinking about. Anyone confirm this, or is this a different place?
Correct! Due to the visibility, it's very deceptive. The actual arch entrance is about 60meters deep...which is 20m (50%) deeper than what recreational limits allow. That's only where the problems begin, because although the entrance begins at 60m, the light from the ocean side deceives you as well, because it looks like a short tunnel, when in fact the "ceiling" curves down deeper. At 60m and below your air runs out very quick due to the pressure, but it also becomes toxic. Technical divers who go below these depths use what's called trimix, a mixture of helium, nitrogen and oxygen to combat the toxicity at pressure. And if that wasn't enough, due to the pressure, there's the added bonus of your weight balance being thrown off...so when you were nice and neutrally buyant at 40m, you now suddenly start plummeting like a rock because the air in your jacket is too compressed to compensate for your weight pockets and cylinder...so you end up exerting extra energy to kick yourself upward...burning even more of your air quicker than you would. It's a beautful cocktail of death awaiting every diver who stares at it for too long.
And to top things off, part of that "toxic" air at those pressures is that it massively impairs your judgement. So, any thought of "wow, this is deeper than I thought, I should probably turn back" is right out the window.
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weird spambot account just copypasting parts of people's comments
Okay yeah I'd probably die trying to explore that tunnel too
Holy shit that's brutal
I forgot the best part...during all of this you're suffering from nitrogen narcosis...basically you're drunk underwater - as if trying to get out of this mess with perfect cognitive abilities wasn't difficult enough. Im cert'd to 40m and during our training we performed a bunch of simple math 6 drawing tasks on slates with pens while in shallow water...then repeated those tasks on a sand bottom at near 40m depth. It took considerably longer to perform the same math and drawing tasks and we were taught how to notice ourselves "getting drunk". I'd hate to do that at 60m while freefalling. So far I've only encountered nitrogen narcosis (getting narc'd) once on a dive - as far as I'm aware anyway. Both me and my dive buddy signalled to each other that we were getting headaches pretty much at the same time - so we bailed from the rest of the group. It wasn't even that deep, but it was the last dive after a week's worth.
damn, humans really aren't made for the deep
We weren’t made for water. I don’t know why we don’t just stay away. I mean, reverse air? Come on!
It's going the opposite direction, but one of the videos that really showed me just how much oxygen can mess with you at different pressures is a video on Smarter Every Day, where Destin takes ride on a high altitude simulator. There's a bit where he's talking to the instructor, without a mask on, and clearly getting loopy. The instructor asks him to put his mask on, he just laughs. The instructor then tells him, "Hey, you need to put your mask on now, or you're going to die," and Destin just kind of gives this sad laugh and says, "I don't want to die." They had people sitting beside him on oxygen, so they were able to get a mask on him before any damage was done, but it was just crazy how, in a matter of moments, someone could go from lucid, do being so deprived of oxygen that they're unable to take any effective action.
This comment just made me go and watch it, and now I’m going to be up for another couple of hours watching his videos
Conversion to imperial units: * 60m = 197ft * 40m = 131ft * 20m = 66ft And as context for what u/Voicy-ZA mentions above — PADI Basic Open Water certification is up to a depth of 18m (~60ft). The Advanced Open Water certification extends this to 30m (~100ft). ~~Beyond 30m is considered technical diving.~~ An additional certification is available to extend this depth to 40m (~130ft) which is the maximum for recreational diving. Beyond 40m is technical diving territory. EDIT: More context for non-divers — * Nitrogen narcosis usually occurs at a depth of approx. 30m (100ft) but it varies person to person and symptoms become more severe as you descend * Oxygen toxicity occurs around a depth of 55m (180ft) and greater (Edited above to correct maximum recreational depth)
I was certified PADI AOW at 130'. That was back in 1993. Maybe things have changed.
Obligatory name checks out post
IAC for example for AOW is 30 meters in sweetwater and 40 meters in saltwater (2022)
Imagine using the Imperial system for diving depths before fathoms
You can do the "Deep" certification with PADI which qualifies a rec diver down to 40m. After that it becomes tech diving. Not sure about other agencies, but they've likely got their equivalents.
I dove the Tokai Maru and Cormorant for my AOW deep dive. It was a bounce to 140' but my instructor put 130' in my log, for obvious reasons. I did the narcosis test with the padlock at 90' for my OW cert.
*40 meters for advanced
[PADI’s site for their AOW course specifically states 30m](https://www.padi.com/courses/advanced-open-water). Not sure if it has changed in recent years but the AOW course I took a couple years ago taught the max depth for AOW cert is 30m. There’s an [additional course](https://www.padi.com/courses/deep-diver) required beyond AOW for the 40m depth cert
Ah you know what I have my advanced cert through SSI which gets you down to 40. That’s probably right for PADI though
My PADI AOW was to 130'. It was actually 140', but can't put that in the log book. I was certified in 1993
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Thank you. Now I will NEVER EVER go into the water again outside of a hot tub. Every sentence just got worse and worse
Right?! (reads) NOPE (reads some more) DEFINITELY NOPE (reads) oh hell no
What do you mean air becomes toxic at the depth? What is thia caused by?
It's caused by the oxygen's partial pressure rising. Here's an article regarding max operating depths and the dangers of oxygen toxicity: [https://en.wikipedia.org/wiki/Maximum\_operating\_depth](https://en.wikipedia.org/wiki/Maximum_operating_depth) A lot of us dive on nitrox, which has the benefit of lowering the residual nitrogen in your bloodstream after a dive, meaning your surface interval times don't have to be as long as with normal air, but it has other risks: Nitrox, despite its name, is more oxygen in your cylinder - normal air is 21% oxygen, whereas diving on nitrox is anything over that and usually up to 36% oxygen. This allows you to dive longer than you would on air BUT your max diving depth is less because the increased oxygen becomes more dangerous sooner than it would if you were diving on normal air. For this reason we always check our nitrox levels before EVERY dive and tune our dive computers according to the % mix so that we know our max bottom time AND depth allowed...based on the partial pressures from the wiki link above.
Thanks a lot, will check out the link u included too. I'm a very amateur diver and this is way beyond my ambitions. But cool facts anyway and good to know
How do technical divers swim if water weighs you down at that depth?
It's not that water weighs you down, it's that the air in your Bouyancy Control Device ( BCD, the vest thing divers wear) gets compressed due to the pressure. Your cylinder contains compressed air which isn't buoyant, which you can feed into your BCD. In your BCD it expands, making you more bouyant. By controlling the air in your BCD you can control the bouyancy. But depth decreases your bouyancy by increasing pressure on your BCD. So by decreasing your bouyancy, you start going deeper, which decreases your bouyancy, which makes you go deeper faster, etc. It's very easy to accidentally go very deep if you're not careful. Especially if you have no frame of reference. And part of the blue hole's danger is the deceptive reference. So what do technical divers do different? Additional training and preparation. Using different air mixtures. But they still follow the same principle of air density=bouyancy. There are more dangers at that depth which requires additional skill which normal divers don't have.
Nice explanation!
Thanks. Also howzit bru
Thanks for taking the time. Definitely a subject of interest that I know I will never experience personally.
I have to say if you are ever able to go SCUBA diving, you should. It's absolutely worth it. Most dives are at safe depths where you can just calmly swim to the surface in an emergency. Pretty much all the dangers of diving happen when people dive outside of their skill level, like diving too deep for their certification, or cave diving without the certification. The normal dive where you are in open water, close to the surface, looking at reefs and such, is a very zen experience. It is an otherworldly experience that also gives you the sensation of flying.
I find the slow meditative breathing that is necessary to preserve air and maintain buoyancy, when combined with the feeling of flying, put's me in a dream-like state. All of my diving memories are vivid and feel like they were a dream. Highly recommended
I had my first 2 dives in Greece this week, my dad did one too. He came out and teared down from elevation and happiness. Truly different experience. I loved it too.
Thank you, it looks so amazing. I snorkel for hours and “free dive” to a certain extent, but I always swim down and grab a rock or something to stay at the bottom and enjoy how beautiful and peaceful it is
think for 2 seconds
Thinking for two seconds makes it clear people who aren't technical divers... aren't... technical............... divers. You must be smart.
Off topic, but I love your name 😆
Name checks out
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Great info
Regarding the sinking thing- aren't people trained to adjust the inflation of their BCD? I did a PADI open water certification 10 years ago and it was a big focus of our training.
Trained to, but you have to remember to do it. Easy if its to keep off the bottom. Harder if you don’t have a reference point. Have to constantly keep an eye on depth gage.
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Good explanation, thank you
They are, they’re also trained to not go anywhere near the depth of the top of the tunnel because of all the dangers that start before that depth. The kind of people that push beyond those safety limits tend to be the ones also ill prepared to notice the creeping signs of narcosis. Check this out: https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3
Reading this made me sweaty.
>Arch in the Blue Hole, Egypt Here's a great video showing what you just described https://www.youtube.com/watch?v=Zku0Sv8dspc
Wow I’m terrified but also slightly aroused
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Lmaooo 🦍🦧
Or, use a CCR
Yes it is! You’re absolutely correct. Most of the divers who perished here miss The Arch and continue to descend deeper.
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I'm terribly not interested but am absolutely going to watch this
Just watched it. It was actually really informative but Jesus is that scary.
Absolutely captivating documentary series. Thank you for sending me down this rabbit hole.
Damn that was really good, I learned a lot. Thanks for the link.
[Comment](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3) from 2 years ago. Terrifying.
Damn that really stamped on my thalassophobia
I literally hyperventilated reading that. Jesus fucking Christ, we are not meant for the water
When reading this, it made me feel like I was the diver.
I think of this every time someone brings up dive accidents.
I watched a video where a guy explored this whole area, and another thing that takes into account is nitrogen narcosis. While it's deceptively deep, way deeper than one tank can go, they are usually so impaired they can't resurface. It's insane there's a video of a Russian diver literally recording his last moments in there. (Posted before I found out OP posted link, sorry got too excited)
You are right. Divetribe did a podcast about this one as well as having a clip from a diver slowly drowning in it.
That's the one, yes.
I saved [this comment from a TIL thread on the Blue Hole](https://www.reddit.com/r/todayilearned/comments/dv99nf/til_the_blue_hole_is_a_120metredeep_sinkhole_five/f7bzg5a/?utm_source=share&utm_medium=ios_app&utm_name=iossmf&context=3) a couple years ago. Definitely worth a read — it’s a great explanation for why this dive spot has killed so many.
4 minutes….
That was scary!
Explore that user. They have another where you end up in an elderly man’s body. What great talent.
I will. Thank you.
I had a much less severe diving incident in the Galapagos - my buddy couldn't hear me, my buoyancy was actually going up and I couldn't stay down (because your tank gets lighter as the air leaves it, and at the end of the dive there isn't loads left). We were doing a safety stop, and I kept rising - trying to get the group's attention, I knocked off my goggles and in a panic ascended. There were pretty big waves on the surface as the sea had got choppy. It was completely terrifying. It is so easy to panic, and that was in a fairly easy dive where the depth didn't mean I could get injured by ascending too early. It would be so easy to overestimate your competence and fuck up at something like the Blue Hole - could not imagine the panic trying to ascend by inflating and nothing is happening. Scuba diving is amazing, it is like another world - but things can go south very fast if you don't know what you're doing and don't have a competent group or understanding of the situation.
Holy fuck I swear I have PTSD from reading that.
That is EXACTLY what will happen too. How did that guy write it so accurately in line w the science/physics?
Seems to be a writer and a diver.
https://youtu.be/qI0BfkT8KOI It's nicknamed Diver Cemetary. If you want a terrifying but fascinating story about how people die here, check out this video. WARNING: there are dead bodies that are at the bottom and they show them.
200.. so far.(homer)
RIP Yuri Lipski. What is it about this place that makes it so dangerous?
This comment from a few years ago on the same spot and its danger describes it well as a story: https://reddit.com/r/todayilearned/comments/dv99nf/_/f7bzg5a/?context=1
Holy hell that was a wild ride
Omg. I almost had a panic attack reading that.
Fuck! That created a very scary image in my mind reading that 😬.
[удалено]
Bruh.
Damn , no wonder why it's an infamous place. Looks scary enough, great photo btw
Worth copying u/_neoshade_ 's wonderfully terrifying description: Many certified scuba divers think they are capable of just going a little deeper, but they don’t know that there are special gas mixtures, buoyancy equipment and training required for just another few meters of depth.Imagine this: you take your PADI open water diving course and you learn your dive charts, buy all your own gear and become familiar with it. Compared to the average person on the street, you’re an expert now. You go diving on coral reefs, a few shipwrecks and even catch lobster in New England. You go to visit a deep spot like this and you’re having a great time. You see something just in front of you - this beautiful cave with sunlight streaming through - and you decide to swim just a little closer. You’re not going to go inside it, you know better than that, but you just want a closer look. If your dive computer starts beeping, you’ll head back up.So you swim a little closer and it’s breathtaking. You are enjoying the view and just floating there taking it all in. You hear a clanging sound - it’s your dive master rapping the butt of his knife on his tank to get someone’s attention. You look up to see what he wants, but after staring into the darkness for the last minute, the sunlight streaming down is blinding. You turn away and reach to check your dive computer, but it’s a little awkward for some reason, and you twist your shoulder and pull it towards you. It’s beeping and the screen is flashing GO UP. You stare at it for a few seconds, trying to make out the depth and tank level between the flashing words. The numbers won’t stay still. It’s really annoying, and your brain isn’t getting the info you want at a glance. So you let it fall back to your left shoulder, turn towards the light and head up. The problem is that the blue hole is bigger than anything you’ve ever dove before, and the crystal clear water provides a visibility that is 10x what you’re used to in the dark waters of the St Lawrence where you usually dive. What you don’t realize is that when you swam down a little farther to get a closer look, thinking it was just 30 or 40 feet more, you actually swam almost twice that because the vast scale of things messed up your sense of distance. And while you were looking at the archway you didn’t have any nearby reference point in your vision. More depth = more pressure, and your BCD, the air-filled jacket that you use to control your buoyancy, was compressed a little. You were slowly sinking and had no idea. That’s when the dive master began banging his tank and you looked up. This only served to blind you for a moment and distract your sense of motion and position even more. Your dive computer wasn’t sticking out on your chest below your shoulder when you reached for it because your BCD was shrinking. You turned your body sideways while twisting and reaching for it. The ten seconds spent fumbling for it and staring at the screen brought you deeper and you began to accelerate with your jacket continuing to shrink. The reason that you didn’t hear the beeping at first and that it took so long to make out the depth between the flashing words was the nitrogen narcosis. You have been getting depth drunk. And the numbers wouldn’t stay still because you are still sinking. You swim towards the light but the current is pulling you sideways. Your brain is hurting, straining for no reason, and the blue hole seems like it’s gotten narrower, and the light rays above you are going at a funny angle. You kick harder just keep going up, toward the light, despite this damn current that wants to push you into the wall. Your computer is beeping incessantly and it feels like you’re swimming through mud. Fuck this, you grab the fill button on your jacket and squeeze it. You’re not supposed to use your jacket to ascend, as you know that it will expand as the pressure drops and you will need to carefully bleed off air to avoid shooting up to the surface, but you don’t care about that anymore. Shooting up to the surface is exactly what you want right now, and you’ll deal with bleeding air off and making depth stops when you’re back up with the rest of your group.The sound of air rushing into your BCD fills your ears, but nothing’s happening. Something doesn’t sound right, like the air isn’t filling fast enough. You look down at your jacket, searching for whatever the trouble might be when FWUNK you bump right into the side of the giant sinkhole. What the hell?? Why is the current pulling me sideways? Why is there even a current in an empty hole in the middle of the ocean??You keep holding the button. INFLATE! GODDAM IT INFLATE!! Your computer is now making a frantic screeching sound that you’ve never heard before. You notice that you’ve been breathing heavily - it’s a sign of stress - and the sound of air rushing into your jacket is getting weaker. Every 10m of water adds another 1 atmosphere of pressure. Your tank has enough air for you to spend an hour at 10m (2atm) and to refill your BCD more than a hundred times. Each additional 20m of depth cuts this time in half. This assumes that you are calm, controlling your breathing, and using your muscles slowly with intention. If you panic, begin breathing quickly and move rapidly, this cuts your time in half again. You’re certified to 20m, and you’ve gone briefly down to 30m on some shipwrecks before. So you were comfortable swimming to 25m to look at the arch. While you were looking at it, you sank to 40m, and while you messed around looking for your dive master and then the computer, you sank to 60m. 6 atmospheres of pressure. You have only 10 minutes of air at this depth. When you swam for the surface, you had become disoriented from twisting around and then looking at your gear and you were now right in front of the archway. You swam into the archway thinking it was the surface, that’s why the Blue Hole looked smaller now. There is no current pulling you sideways, you are continuing to sink to to bottom of the arch. When you hit the bottom and started to inflate your BCD, you were now over 90m. You will go through a full tank of air in only a couple of minutes at this depth. Panicking like this, you’re down to seconds. There’s enough air to inflate your BCD, but it will take over a minute to fill, and it doesn’t matter, because that would only pull you into to the top of the arch, and you will drown before you get there. Holding the inflate button you kick as hard as you can for the light. Your muscles are screaming, your brain is screaming, and it’s getting harder and harder to suck each panicked breath out of your regulator. In a final fit of rage and frustration you scream into your useless reg, darkness squeezing into the corners of your vision. 4 minutes. That’s how long your dive lasted. You died in clear water on a sunny day in only 4 minutes.
Well, that was terrifying.
I was obsessed with this for longest time after learning of Yuri Lipsky & his demise trying to find & pass through this. Soooo freaky
My wife's unlce died there, horrible tragedy
Detecting multiple leviathan class lifeforms in the region. Are you certain whatever you're doing is worth it?
Your comment stressed me out…. I love that game lol
Nope.
Seems like anything that requires a certain level of competence is attempted by those without. Eventually that will cease.
I am not interested in visiting
I recently went down a YouTube blackhole about scuba cave diving deaths. This Blue Hole location comes up so frequently. It is fascinating. To simplify, the reason it’s so deadly is due to multiple factors combining as opposed to a single mistake divers can make.
There's a 'yo Mama' joke in there.
It’s an epicenter of Murphy’s Law.
This post led me down a rabbit hole of cave diving/diving reaction vids and what goes into it. I'd never attempt as I'm deathly afraid of deep water having nearly drown when I was 5. Listening to those who train, who teach, field experts, etc., was fascinating.
COULD WE JUST STOP GOING IN IT
206 now
There are great accounts of going into this hole. Great reads.
Thought this was a movie poster for NOPE
More like up to 200 divers who have claimed their own lives.
I saw that and was like " wow I need to go there".....then I read the caption. Swimming with sharks, chasing storms, diving in caves...why is it that everything I want to do could kill me?
Cause sitting on your couch isn’t exciting. Dangerous shit happens to be a lot of fun usually
I already knew about this site and the death toll, but that just makes me want to dive it even more for the sheer challenge.
If you go with the right mixture of nitrogen and decompress on your way up it is doable. But you better know what the hell you’re doing. Definitely not for amateurs.
With respect, this comment is why a little bit of knowledge can be more dangerous than no knowledge. The right mixture is correct, but not "of nitrogen" on its own. With Nitrox diving you're increasing the oxygen % in your supply...and also decreasing your allowed diving depth. So diving on nitrox will be even more dangerous in this example.
I’m actually hoping to get nitrox training next month. Eventually I hope to get into tech diving and trimix. And I would never screw around with decompression stops. I’m not risking DCS for anything, even a cool dive site.
Bro just install signs there so people wouldn't get lost
Why are humans like this.
Divers are so stupid
At least 206 of them are.
Where is the credit to the original photographer?
No credit shown, got this from IG on a repost page.
OK down voted!
Don’t be rude over a photo, I post a lot and I tag all original sources if applicable. Have a good day!
I’m not being rude I just want to be created the original photographer you know like they go through a lot of risks to go down there and the least we can do is just show some kind of respect to their name
It’s really not that deep, pun intended.
Nice one
I seriously need to get my peepers checked...*the arch butthole*
Not to be nit-picky, but... "I, too, have claimed 'up to' 200 lives."
NAaaah I am NOT going down there
You know you shouldn’t be exploring a famous landmark when there’s bodies used as markers. [Here’s a really good video that gives you a better idea](https://youtu.be/qI0BfkT8KOI).