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The Blue Hole in the Red Sea is the deadliest dive site in the world

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Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#271
post #264
post #221

Earlier quoted context omitted.

Those who followed first sentence instruction did correctly one question. And ignored all the others in test that was supposed to be graded on completeness. He also claimed the goal was to gauge their knowledge. Again, that was lie. And those who scribbled were literally trying to fulfill stated goal of test. > It will be graded on completeness, not correctness. You are not expected to know all the answers. I'm just…

Given a set of mutually conflicting directives, one must exercise discretion to prioritize. I felt (at the time and reflecting on the experience now) that it was clear which held the higher priority.

To me, ignoring that one and answering questions gives more sense.

According to instructions, the test was judged on completeness. The instructor expected the students to pick set of instructions that make test less complete.

In this variant, answering majority of questions and leaving that one missed is rational behavior.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#272
post #44

Earlier quoted context omitted.

I'm an avid diver and I completely agree. My Open Water took place in a hot spring with extremely low visibility. The goal was the cert it wasn't skill mastery. My next dive was the Great Barrier reef where boats just drop you off and you can get a guide or dive yourself. We irresponsibly dove by ourselves, exhausted all our air, and came up (skipping a safety stop) realizing we were a considerable distance from the…

I remember my padi instructor (British, in Malaysia) as being completely paranoid, which was a good thing. He essentially told us that any missteps would have very nasty consequences, and spent most of his time badgering us with safety precautions. He also encouraged us to dive with a guide, do refresher dives, etc. The only downside is that I don't dive anymore now that I have kids, since I believe it's dangerous, a…

Interesting, I also got my open water in Malaysia. My South African instructor spent a lot of time drilling safe decent / safe ascent practices into us, making us practice individual and buddy drills etc. I will always be grateful to him for instilling good practices from the get-go.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#273

Earlier quoted context omitted.

Of course, because things very rarely go south, especially to the point of someone dying. But still, spending half an hour reviewing some basic course material is not a huge thing to ask.

Yes, it is certainly acceptable to ask for that. Not arguing that. Merely pointing out that there is no evidence for the assertion as stated.

I interpreted it as "they don't understand the dangers implicit in diving", i.e. they don't have the right mindset for diving.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#274

Earlier quoted context omitted.

> become too stupid to save yourself. You probably weren't too smart to begin with to go to 50m on compressed air, and without a seafloor at that.

I haven't been to the blue hole, but I can easily see nonchalant guides leading people to ignore any misgivings they had from what little training they may have had years ago.

I can see someone with a 30m certification going to 40-45m. But anything below that ought to be a huge "no" for anyone who's done the basic deep dive training, in fact you should be running away as fast as you can.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#275

I've dived the Sinai's Blue Hole, so it's wild to see this on HN. It was an intense experience. Our dive instructors warned us of how deadly the site was, and the various hazards. But the dive itself was unique compared to other deep dives I've done. I would describe it like parachuting, slow motion, into the bluest blue. By the second, the sunlight got dimmer and the blue got bluer. It was disorienting if you looked…

Smart person, and it takes courage to not go (down) with the crowd. The people who don't come back up are the ones who lack your good judgment, I expect.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#276
post #271
post #264

Earlier quoted context omitted.

Given a set of mutually conflicting directives, one must exercise discretion to prioritize. I felt (at the time and reflecting on the experience now) that it was clear which held the higher priority.

To me, ignoring that one and answering questions gives more sense. According to instructions, the test was judged on completeness . The instructor expected the students to pick set of instructions that make test less complete . In this variant, answering majority of questions and leaving that one missed is rational behavior.

The test was graded on completeness no doubt. Grade = completeness == 0 ? Pass : Fail.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#277
post #201
post #122

I'm an experienced diver (PADI dive-master, ACUC instructor, IANTD gas-blender and normoxic trimix diver, TDI hypoxic trimix diver and dive-master) with several thousands of dives of which many at 100m+ (330 feet) depths. I lived in Dahab where for 16 months I assisted training technical diving instructors in the blue hole and at other less touristy dive sites around there. The blue hole is in not a particularly dang…

Question: Why are divers injecting this trimix?

I don't recommend anyone "inject" trimix ;) But jokes aside : Trimix is an (artificial) gas blend that includes helium, which is an inert gas that your body doesn't metabolize (though their is still a lot of unanswered questions about its effects below 250 meters). Your body metabolizes gases (normally only Oxygen) according to their partial pressures in your body. The partial pressure of Oxygen at sea level is just 21% (there's an atmospheric pressure of 1 Bar and air is 21% Oxygen, 78% Nitrogen, and 1% Aragon and other weird stuff), but as you dive deeper into the water and the ambient pressure rises, so does the partial pressure of Oxygen and Nitrogen. Oxygen becomes toxic around (to be safe) 1.2 ppO2 and Nitrogen causes narcosis at a pp that varies greatly from diver to diver. As a rule of thumb, somewhere between 40 and 60 meters is where things get dangerous. So, to reduce the partial pressure of these gases, Helium is introduced, reducing the proportion of the metabolized gases in the total mix, and allowing the diver to go deeper before the critical thresholds are reached. To dive below a certain depth (about 60 meters), a mix is required where the proportion of Oxygen is less than the minimum 17% Oxygen at 1 Bar required for your body to function. We call these mixes "Hypoxic Trimix". A typical deep technical dive involves switching gases (different tanks) at least three times during the dive, and grabbing the wrong regulator is a deadly mistake. Technical diving is not for the distracted. It is, also, the slowest and most meditative rush you'll ever experience. Add overheads and caves and it really does feel like an excursion to an other planet. Speaking of space travel : more humans have been to space than below 200 meters.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#278
It should be pointed out that the record depth in the area is not Tarek Omar's 203 meters as the article mentions, it's Nuno Gomes' 318 (https://en.wikipedia.org/wiki/Nuno_Gomes_(diver)). This, with all due respect to Omar who is indeed an incredible diver.

Also, the article speaks of mermaids so I'll just add on a lighter note that for a long while there was a toy mermaid tied to the over-hang mid way through the arch.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#279
post #5
post #3

Earlier quoted context omitted.

Though I'm sure it's a fascinating interview, I thought the article was really well-written and helpful. I really enjoyed the pace of it all.

You might also like this story about a dive in Boesmansgat: Raising the Dead[0] [0] - https://www.outsideonline.com/1922711/raising-dead

My dream is to see Werner Herzog do a film about this.
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