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The Blue Hole in the Red Sea is the deadliest dive site in the world (spiegel.de)
323 points by pmcpinto on April 27, 2021 | hide | past | favorite | 293 comments



I'm an avid diver; got certified as soon as I turned 12 years old and have had some great adventures and life lessons diving and continuing my training and education. After many many conversations and encounters on dive boats with others (some seasoned, most tourist / rec divers) - I believe that 90% of the industry sees diving akin to a roller coaster ride instead of Skydiving. The risks with scuba are there for you to see and the situation can get deadly very quickly, but most people don't see the inherit risk or shrug it off. I've watched countless divers who are renting their bc/reg/tank/computer not even go through the most basic safety checks prior to diving. They simply trust the operator and jump in. This is not a "batteries included" sport. It is that lack of preparedness that leads to fatal accidents, people who don't respect the sport for what it is and the dangers that come with it. If you don't plan your dives, understand the dive profile, then you are going to panic of make a stupid decision when you shouldn't. When I was younger, technical dives; cave and deep, where my two favorite things to do, the amount of planning it took to pull off the dives was enjoyable and I enjoyed pushing myself in to those situations and the focus it required. Now that I have kids, I won't do those dives anymore b/c I understand that when you plan them, there is a greater than 0 chance that you don't come back and its not worth it to me to take that chance.


First class of dive course at CWRU:

Older Navy diver instructor walks in "So I know each of you is coming into this class with different levels of experience. What we're going to do first is a short test on your proficiency for 20 minutes.

It will be graded on completeness, not correctness. You are not expected to know all the answers. I'm just interested in gauging what you know.

Be aware, there are a lot of questions for the time, so I suggest you work quickly to get through all of them. Make sure you read and follow all instructions.

Do not turn your paper over and start until I've handed all of them out and said go.

hands out tests

Go."

12/14 people in the class start furiously scribbling

The first sentence on the test?

"If you read this sentence, please continue to hold your pencil, but do not write on this test. Wait until time has expired."

It always stuck with me as one of the best lessons about diving. Both in what you should do, and what our natural inclinations to actually do are.


We had a Chemistry teacher who tried a similar sort of thing on us when I was about 17.

"OK class, today's lesson is going to be a dictation, get your books out and start taking this down"

I can't remember the exact content but effectively he started off with some familiar organic chemistry and then veered off to stuff that was pretty obviously wrong.

I'm proud to say that I'm the one that said "Eh ... that doesn't seem like a valid equation ... ?"

"Good! Never just copy this stuff down without engaging your brain!"

(Or at least that's the way it goes in my memory, 17 was a long old time ago!)


I was not a great student but at one point in college I realized that I wasn't listening while taking notes. I was just mindlessly copying everything exactly as was written on the white board missing out on what my teachers said.

I stopped taking notes at this point and started paying attention instead. My grades improved. This might not work for everyone but something to try if you struggle retaining lecture content even as you take a bunch of notes.


In a physics or maths class that seems impossible unless the prof is teaching directly from distributed notes or the text book. Some of the better classes I had were those where the prof just gave out their notes and we could focus on what was said rather than writing it out, in that case if you zone out it's your fault.


Actually I was a Math major the biggest thing for me is 1. notes can be very cryptic after the class without the verbal context. A lot of course also have that advantage where the teacher would provide notes afterwards so yeah focusing in on what was said was the highest value.

It was my fault that I zoned out, that's why I had to find a way to avoid it.


Funny, for me it's the opposite. Can't remember it if I don't write it down. I don't have to read it afterwards, I just remember what it was by remembering writing it.


I've found that taking notes in cursive helps my listening comprehension, for whatever it's worth. But it makes it harder to use my notes as a reference later.


yes, ive had similar experiences, and thinking back on it, why take notes when you can just record the lecture and play it back later.... better to engage in the lecture, since thats why we are there in the first place!


We had a similar one of those in school. The first question of the test was 'read all questions before you start.' Then it had stuff like poke holes in the paper, draw things, random stuff, the very last question though was,

'Now that you've read all the questions, just write your name in the top corner and turn your paper over.'

Yeah...a lot of my classmates ended up with holes and scribbles on their tests...


It’s pretty ambiguous, though. In tests you usually complete all questions. Why should you in this instance only complete the first and the last task?


  When you are doing a safety check list, you don't skip and do whatever part of the checklist you feel comfortable doing. 
  You do it from top to bottom. 

  Multiple people have died in accidents because they focused on small issue ignoring the larger problem.

  So when it's time to check safety in scuba diving, you should better follow the instruction instead of doing whatever you want. 
  Example. There is no point to worry about "Is your mask clean?" when you are going to run out of oxygen and drown.


If you are still unsure of the why, then you have had a fortunate life. There are many times you will get a set of "instructions" where somewhere something is wrong or incomplete, but you won't know that until you've worked your way through them. Ikea comes to mind. It is often very helpful to read through all of the steps involved first to make sure you actually have all of the parts/pieces you need and to make sure they make sense before starting. So I say again, that if you've never run into one of these situations, then you've been lucky.


I’m not questioning that you should read all the questions, I’m saying it’s ambiguous what you should do if you’re given the following task list:

    1) read all tasks
    2) do x
    3) do y
    4) do z
    5) now that you have read all tasks, just write your name and do nothing 
I don’t understand why I should not do x,y,z. Task 1 is telling me to read all tasks, not to execute any. Why should one, when reading 5), decide to execute that particular one, but not the other ones?

To me, the correct procedure would be to read all tasks (task 1), then continue executing task 2), etc.


The teacher also told us specifically to read everything before also doing anything.


1.) The complete set of instructions was inconsistent and mutually exclusive. The two questions required mutually exclusive actions. Why pick last?

2.) That is standard boilerplate typically said due to people not reading whole questions. And it is not useful advice in general.


I had one of those in fourth or fifth grade. It had items like "squawk like a chicken", making it obvious to everyone whether or not you read the directions.


I was one of the kids with holes in my paper. It taught me an immediate and memorable lesson. Attention to detail.


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 interested in gauging what you know.

In overwhelming majority of situations, of you sabotage goal of event due to following likely faulty mutually conflicting instructions, you will be blamed for it.


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.


> Make sure you read and follow all instructions.

I'd be worried about someone who receives that instruction, receives an anomalous instruction on the test, and decides to ignore the anomalous instruction.


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


Other versions of this test include the last question being "Don't answer any questions". The habit the teacher was trying to impart was "read the whole paper" first before answering any questions -- particularly if there are multiple choice questions.


One of my middle school teachers gave that sheet out to the class. I was that one kid that took it seriously, but had no prior-example knowledge to even bother reading ahead.

The test with the bail-out at the start sounds logically fine. The test I was given was just a cruel trick from a trusted source of tests / knowledge provision.


This is an irrational party(professor) trick that wastes everyone's time.

An argument could be made for "read the (short) instructions at the start". An argument cannot be made for this. There is often very little value to skimming the entire question set before the exam.


It's been a very long time since I had to do any tests, but back in my school days, with multiple-choice tests, I evolved a method of quickly answering everything I was confident to know 100% throughout the entire test in a first pass, reserving the rest for subsequent increasingly slower passes.

What tended to occur was the earlier fast passes at the very least warmed up the cache upstairs, and some previously unclear questions became obvious. Then for the remaining questions, they often had dependencies with other questions and their answers, which I could use to deduce probably correct answers.

This was obscenely effective. To the extent that I would ace tests in classes I barely attended and never turned in homework for, in some cases culminating in teachers publicly accusing me of cheating on the exams. Though some of that was also due to switching from private to public school where I had already learned the material in the previous years.


I once used this method and spent the last ten minutes of a test just guess-and-checking the solutions to a question I didn't remember the formula for. Of course, it was the last one I checked. (I wasn't confident enough to early return).


I used the same method and can confirm it was very effective for me as well.

An added bonus is reduced stress about time limits. After the first pass you have a big chunk (if not most) of the test done in little time - this feels good and also leaves you with a clearer idea of how much work and time is left.


I don't know about you, but for my tests on a curve where I might not be able to answer all the questions, doing the quick skim to answer the low hanging fruit before getting to the harder problems is a good way to make sure you don't run out of time and lose out.


I did the same, but if I'm doing that skimming and I know the answer to question 12 is (c), I fill in (c) and keep going. I don't read all the questions, then go back and try and remember which of the questions I knew the answers to off-hand. Instead, I'd do the test in 3 passes.

1. Answer all questions that I know the answer instantly or (for math type tests) can solve within a few seconds. Skip anything not quick. 2. Go back and answer questions that I know I can solve. These usually take a minute or two (since the easy ones should already be done). If there happens to be a question I know I can solve but also know will take "too much time," skip it. 3. If there's time left, work through any remaining questions (hopefully there aren't that many), making a best effort to prioritize the ones I'm more confident that I can solve in the time remaining.


Also, content of later questions can be useful earlier, and getting some background brain cells working on the hard stuff while you churn through the easy stuff could be worthwhile.

It's a good lesson, but it's a lesson about taking tests not about the material. I can see arguments for and against including that in any given class.


>content of later questions can be useful earlier

In some tests I have seen future questions answer previous ones. For a contrived example:

"Q1: What color was the bookshelf? A. Red B. Green C. Blue"

"Q2: What sentimental item did John take from the red bookshelf?"

I was never sure if it was on purpose to reinforce reading all questions before answering or if it was merely poor test design. Usually it was more subtle than my contrived example but it did bump my scores on some tests up a bit.


Why would you not answer questions you know straight away? That wastes time.


I agree. More over, half of these have genuinly mutually exclusive instructions.

And from those mutually exclusive requirements you are supposed to pick the "least likely one" else you are wrong. It is good example how manipulation works however. You put people into unsolvable situation and then blame them.


Which is to say diving is a sport that can be safe, but only assuming you are actively and honestly engaged in making it safe.

I am not diving but I am sailing and for the most part sailing is a safe sport assuming you are prepped including mental preparation. If you are not, things can get downhill pretty fast.

I consider diving one of the sports where you place yourself in a situation where you are dead by default unless you have paved the way for you to escape. Same is flying, skydiving but so is going into a corner in a car or motorcycle at the max speed you can handle.


Sailing is one slip away from diving.


Tangential, but driving never quite feels safe if you are pushing the car. At least not without inspecting the entire suspension every month or two. And that's ignoring anything internal, like your clutch fork giving out, or bending a rod, or your inner tie-rods disconnecting, or your brake cable tearing, or...


If you are pushing the car on a public road it means you have already failed at driving safely.

Driving safely != not cause an accident

Driving safely == not be in an accident

You can be the best driver in the world driving the best car in the world and it doesn't matter, because some idiot will not look in their mirror when changing lanes and suddenly you are in an accident.

To drive safely on a public road means to take care for your abilities and your car but most, most importantly, too give wide berth to other road users and to drive in a way that will minimize the accident if it happens.

Understand everybody makes mistakes. If you aim to drive safely you need to make it your responsibility to drive in a way that will allow yourself and others make mistakes and still not cause an accident. In other words, give margin for error.

Some examples:

-- try to minimize your time in somebody's blind spot.

-- observe traffic behind you, not just in front of you. I have on multiple occasions avoided a car hitting me from behind, twice at a difference of speed that looked like at least 100km/h. Being aware where the cars are gives you ability to act instinctively without hitting somebody.

-- try to maintain slow relative speeds with regards to other road users. For example, never drive fast around cars stuck in traffic.

-- always have a backup plan for every maneuver. For example, do not have fast closing speed to the car in front of you with a plan to change the lane just before you hit it. You need to maintain the ability to break in case the car in front of you suddenly slows down or in case you can't change the lane for whatever reason,

etc.


Just to be clear, I am talking about auto-cross and other events, not pushing cars on a public road.


Just to be clear, I specifically mentioned public road.

Driving on a closed track is completely different business.

While definitely not as crazy dangerous as some people would paint it, I don't feel you can ever drive as a sport and be completely safe.

Driving as a sport is by definition pushing the boundary on how close you can get to crash so if you are good at driving it means you are getting closer and closer to the limit.

I think this is confirmed by how many professional drivers died in crashes. And it seems the better you are the higher the chance you will die in a crash.


That’s why people are trying to push for us to stop calling them accidents and call them crashes.


> I believe that 90% of the industry sees diving akin to a roller coaster ride instead of Skydiving

As a licensed skydiver who got out of the sport partially because I didn't like the culture, I assure you that a huge amount of the skydiving industry also views it like a roller coaster ride.


I have a similar theory about motorcycles. It's not batteries included, and some people ride like absolute madmen increasing the fatality rate.


I dropped my motorcycle endorsement when I had kids. There were too many death notices in the newspaper where a guy about my age was killed because a car "didn't see them" and turned right in front of them.

In most cases there wasn't an indication that they were speeding or drunk or on drugs, just that other people weren't paying attention. And maybe that the rider didn't allow for that.


It's not actually the people riding like lunatics that manage to kill themselves on motorcycles at high rates. It's the old guys, riding back from "biker nights" at the bar, in full branded gear to include the do-rag and t-shirt. Lots of single rider, single bike accident with substantial alcohol in the blood.

I've ridden for many years, and I also fly small planes, so I'm quite aware of my higher-than-average risk profile, and have gone through a lot of studies and reading to determine how I can, as much as possible, mitigate the risks while still enjoying the activities.

For motorcycles, riding regularly, in full gear, while sober, gains you an awful lot. Riding infrequently is hard because you don't maintain the muscle memory, full gear turns most crashes into a "Invent new cusswords to remove the paint from your helmet, get up, and walk away" event (not all, obviously, but if you crash without gear, it's going to either suck a lot or end your life, and if you crash in gear it's a lot less likely to suck or kill you), and "bike nights at the bar" are just dumb.

Knowing the limits of your bike is also helpful. I did a few track days, decided I didn't want to go down this route, but very much appreciated the chance to learn (in a safe environment) how much further than my normal limits I could ride on the bike. I couldn't ride anywhere near the limits of my bike, and knew it, but I expanded the envelope of "I know I can make this bike do that," and it was occasionally useful. The guys riding wheelies down the highway, against what most people believe, actually don't kill themselves terribly often. They know the limits of their bike, they know what they can make it do, and if there's something that requires a rapid response, they can make the bike do it on demand. One of those guys has a car pull out in front of them, they're either able to stop competently, or aim for the new gap, lean the bike over, cut through the gap, and flip off the car. The guy who rides a big cruiser 300 miles a year to the bar is more likely to mentally lock up, lock the brakes (before antilocks were standard), and slam into the side of said vehicle. Often while sliding on the ground first, having locked the rear tire.

You also, if you're riding regularly, learn in a hurry how to identify the cars to watch out for. Maybe the slammed Honda with a fart can, park bench, and body damage is being driven by someone's mom, who is the most respectful person on the road. Don't care, I'm going to assume it's likely to do something very abrupt and stupid. And, often enough, they do.

But if you wear gear, ride a lot, and understand the limits of your bike, you can manage a lot of riding miles, very safely. As much as people make fun of the old couples on Goldwings in the glow-stick yellow riding gear, a lot of those people ride 30k+ miles/yr, for many, many years, entirely safely.

This is getting long, but general aviation accident records contain a lot of the same sort of thing - "Here's a short list of quick ways to die in an airplane. Don't do these and your life expectancy will increase dramatically."

And nothing here means that you can control all the risk. Sometimes, shit happens and there's nothing you can do about it, despite all your preparations (Gann's Fate is the Hunter is a great read on the subject). But you can radically balance the scales in your direction with the right planning.


In the United States, cops pull over most bikes, especially after 10 pm. It's almost like they just hate bikers?

The bikers I know are not getting buzzed at the local watering hole, and aiming the bike home. It's not the 70's.

In my county, the fatal bike crashes are usually new high end high performance bikes, on country roads. They are experienced, but pushing it. They are cold sober.

The days of having a few beers, and driving home on the bike, or even an old car, must be down across the county?

Cops realized a while ago that most Americans have no qualms over arresting a guy over a DUI, and they are villigant.

To vigilant in my opinion. (I heard in Texas if a dui defendant can prove they were not physically, or mentally impaired, while doing a computer simulation, they might get out of a dui? This might be just a rumor? I feel it's more fair, especially when a marginal dui can significantly impair your economic viability for years, especially for the poor.)

In upper class neighborhoods, it's usually the only crime they can solve, after pulling over 50 sober drivers?

My brother got a DUI over .04 BAC. He also had weed in his system from the day before, and clumsily told the cop the truth when asked. Bored officer, "Did you take any drugs?". My naieve brother, "well yesterday I smoked some weed.". Arrested, and lost the case.

My point is the DUI scare is real among everyone, but the naieve.

When I had my motorcycle, I was pulled over so many times for no reason it was maddening. It's the main reason I don't ride anymore.

Getting pulled over for no reason other than a cop hoping to nab a marginal dui is really irritating.

I've gotten to the point where I have two dash cameras always activated, and I try to not go out past 10 pm in an old car.

(I can offer this, if you are ever in Marin County CA, expect to be pulled over if driving a motorcycle at night. Also expect to be pulled over if you look ethnic, or drive an older vechicle. We have a bunch of bored cops, and they look for anything they can to fill up that duty sheet. Oh yea, they peer into bars, and follow patrons home.)


Marin County will also pull you over on a bicycle because they don't like cyclists. And issue several hundred dollar tickets for going too fast, passing cars while they are stopped in a turn lane, riding over a crosswalk with small children... https://twitter.com/WarrenJWells/status/1386328677378494468?...


Thanks for this thread. A weird experience makes sense now: I met this man when he was on a bike. I figured it was a local asshole trying to be aggressive to a stranger in front of the woman he was riding with, with maybe 20% odds of also being an off duty cop.

Either that, or the Sausalito community just really shares a passionate opposition to cyclists rolling along the uncontested sides of quiet T intersections.


One part of being human is the ability to rationalize situations rather then be rational about the situation. Two very different things.

Our biases prevent us from recognizing this in ourselves ever.

Not saying you're rationalizing your behavior, but I'm saying it's a possibility. The only way to know for sure is to provide data to back up what you're saying.

What is your statistical risk profile based off of the conditions your provided?


It's certainly a possibility, and I've not sat down with a spreadsheet to optimize my risk profiles.

I like riding motorcycles, so I try to do it in as safe a way as reasonably possible. Right now, given that I'm typically on ill-handling sidecar rigs, that involves gear and no longer riding two wheels frequently.

I like small planes. Again, I try to find safer ways to do it.

But I recognize that these are still riskier activities, and I do them because I enjoy them, entirely aware of the risks involved.

"Trying to do the research to be able to quantify my risks and mitigations in a spreadsheet" doesn't sound terribly enjoyable to me, so I've no intensions of doing it.


The median age of riders is ~50 while the average age of fatalities is 42. People over 50 make up significantly less than half of fatalities.

However, you are still kind of correct- the number of fatalities picks up strongly at 50+. People 35-45 tend to be the safest. People 50+ are still on average significantly safer than <30, even those who are first riding late in life.

Motorcycle fatalities are heavily associated with risk-taking more than anything else. There are more people like that <30, but there are plenty of Boomers riding recklessly as well. 27% of motorcycle riders in fatal accidents are alcohol-impaired, by far the highest of any vehicle category. Passenger cars and light trucks are 21% and 20%.

Data from NHTSA summaries


> motorcycle riders in fatal accidents are alcohol-impaired,by far the highest of any vehicle category.

I think this is attributable mostly to the fact that fatality rate on any motorcycle accident is higher (for obvious reasons) and that alcohol is especially a contributing factor to single vehicle accidents.

If you are tipsy and go into a corner a bit fast in a car you can usually react in a way that will save it; many "gut" level reactions on a motorcycle will cause bad things to happen (e.g. most braking while already in a corner). Touching a soft shoulder is much, much easier to recover, etc.


> The median age of riders is ~50 while the average age of fatalities is 42. People over 50 make up significantly less than half of fatalities.

I'm not sure if you were trying to imply there was some connection between those sentences? You could easily have more than 50% of fatalities over 50, and still get an average of 42 (for example, deaths clustered mostly in either twenties or fifties).


> for example, deaths clustered mostly in either twenties or fifties

Which I think is the point. Very young riders are in fact crashing a lot - something parent claimed is a myth.


Are they? Cause motocycle incidents I knew of were all young overconfident guys. No alcohol was involved and it was during the day. The traffic rules were broken tho (speed and aggressive riding).

Anecdotal, but still.


> It's not actually the people riding like lunatics that manage to kill themselves on motorcycles at high rates.

There are a couple of high risk groups. One is young guys with a combination of inexperience and a desire to go fast(er than conditions/skills allow). Another is older guys, often who haven't ridden for years if ever, who get into trouble. Again inexperience is a big factor in both.


Last time I looked at the numbers, the peaks were at 6 months to a year of experience riding, and the second at 3 to 4 years. The first peak being generally due to inexperience, the second to overconfidence.

Lack of regular experience is definitely a contributing factor. Muscle memory has a half life.


> Muscle memory has a half life.

Indeed. This is part of why I sold one of my motorcycles - a powerful, fairly aggressive sport touring bike. It was my daily driver for about 2.5 years, and I rode it typically 7 days a week, around 1300-1500 miles a month. I knew the bike, and I had the "edge" - there was no question about what the bike was going to do. I knew it, I knew how it responded, I knew what I could ask of it. If I didn't ride for a few days, I could feel that the edge was dull when I got back on - there was just a little something missing, corners were a smidge sloppier, etc.

And I was no longer riding enough miles on that bike to keep that. I knew I was ham fisted when riding it compared to what I used to be, and I just don't put enough miles on anymore that I was able to keep it up.

I now ride the motorcycle version of a Russian tractor (one of a few Urals - sidecar rigs), and they're both entirely different from two wheels and demanding in different ways. But they don't have the sort of instant response of a sportbike either. A good sportbike does what you asked, right now. Capable of it or not, it does what you told it to do, and if that includes an unintentional wheelie, well, you did ask for it with your throttle inputs. The Urals have their own nasty handling corner cases, but are a lot more forgiving in many ways, and you really have to muscle them around at times. A subtle input gets entirely ignored.


For broadly similar reasons I have a 650cc twin sports tourer. It is docile, mild mannered, and has enough reserve power at the speed limit should I need it.

I don't want or need anything more.


The older guys scare me more, especially on scenic drives like Blue Ridge. They can outright bully normal drivers (surrounding them to force them to go faster). Of course, these are the vast minority of motorcyclists, but it's still a recurrent issue.


One thing about places like the Blue Ridge is they are popular enough for tourism that they draw people from all over the country - including those who have never or rarely driven similar roads. That plus being crowded can be a perfect storm for stupid accidents.


Interesting. I'd be curious to read your thoughts on mitigating risk with general aviation. Is there a checklist somewhere of "always do these 20 things" or do you have to comb the NTSB accident records yourself?


You don't have to comb the NTSB records - they're aggregated by various groups.

A lot of them involve loss of control of some form or another - typically in instrument flight conditions, often enough by someone who either doesn't have an instrument rating or is badly out of practice. A VFR only pilot in the clouds has a lifespan measured in minutes.

Running out of fuel for some reason is depressingly common - and while an off-airport landing isn't automatically fatal, "pilot failed to monitor fuel in flight" is a pretty stupid reason to crash.

And avoid light twins. They're a lot more demanding when an engine fails, and typically don't handle off airport landings very well. There don't tend to be many injuries with twins - either you handle everything properly and land safely, or the aircraft leaves a small smoking crater in the ground.

A lot of it is simply looking at the sky, forecast, and deciding "You know, this just isn't a good day to put a small airplane in the sky." I consider night VFR to be fairly risky too. Clouds are invisible, visual illusions in sparsely populated areas are common, and it's hard to find a nice flat area to land if your engine quits at night.


Sometimes this just makes me think that every pilot needs some IRF experience and a fuel gauge that has an alarm that says 'land now, you moron' or such.


Small airfcraft fuel gauges are notoriously unreliable. If it's reading low, yes, be alarmed. But sometimes the float gets stuck, so if your estimate for how much fuel you should have burned puts your fuel lower, trust that.

At least in the UK, getting a private pilot's licence did involve a couple of hours of simulated IFR. Not enough to do anything complex. But enough to turn 180, and be able to follow detailed controller instructions.


In the US, you need a couple hours of simulated instrument time as well. One difference in the US is that you can legally fly VFR at night - even if it may be unwise in a lot of areas. A lot of countries (I believe the UK is one of them?) require an instrument ticket for flying at night.

If you're up over, say, Iowa at night? Tons of farms, flat, lights everywhere? It's fine. Pretty, you can still see stuff, and short of an invisible power line for an off airport landing, it's almost like flying during the day.

Out in Idaho, in the mountains? You're pretty dumb to fly VFR at night. There's no light anywhere, lots of hard rock, and plenty of clouds that like to appear with no warning.

But, yes, fuel gauges suck. The problem is that even if you put something like a fuel totalizer in, you still only know how much has gone into the engine, not how much is left in the wings. I understand a loose or missing fuel cap will drain a Cessna's wing tank in about 10-15 minutes.


Huh. Wait, aircraft use float based fuel gauges still? I thought everything had gone electro-resistive since you'll get the same measurement regardless of orientation of the tank if you place your sensors right.

I remember coming across that as a specific design challenge to overcome. Floats don't read the same when flying upside-down.


Most of the US General Aviation fleet is from the 1950s to 1980s. They still use floats.

Those who fly upside down on purpose tend to either not care about the fuel readings when upside down, or fly something modern enough. But I can't imagine an airshow performer is paying any attention to the fuel gauges. "I have a 15 minute routine, I have an hour of fuel onboard, and I'm surrounded by an airport, which is a good place for an emergency landing."


> I'd be curious to read your thoughts on mitigating risk with general aviation.

It seems like one of the big ones is simply: "Don't go up in shitty weather."

Too many people are dead because they just had to fly in crap weather.


“not even go through the most basic safety checks prior to diving”

From my experience the dive operators in tourist spots often don’t want you to touch anything. Kind of makes sense because most tourists like myself only have a very vague recollection of the procedure.


It's a vicious cycle though: tourists don't know how to dive safely so instead of making sure they know, we'll just set up their gear and throw them in the water. Tourists learn that this is normal, and become even less likely to know how their gear should be configured, which makes the next operator more confident in their decision to not let the tourist set up their own gear.

The crew on a dive boat in a tropical destination could very well be a 20 year old newly certified divemaster who's been up all night partying - there's no way I'm letting that person be responsible for making sure my air supply is connected and turned on before throwing me in the water, or any of the other standard pre-dive (BWRAF) safety checks that all certified divers are taught to do.


The problem dive locations have is a lot of people a) overstate experience or what they remember, b) are unfamiliar or have not tested equip they will be diving with and c) equip is not familiar to operator if they bring their stuff.

People don't dive enough. So they buy all sorts of new stuff for their big new drift dive vacation. In some cases they've literally not been underwater with it for even 20 minutes. Also makes it harder to do an at a glance x-check for folks if you don't know their gear. And some gear harder to deal with (ie, adding weights underwater) if someone turns out underweighted.

My own feeling - unless someone is current with their equip or has current diving - start with a hard bottom dive at 40'.


You touch on what I think is an important consideration. A lot of people want to get into diving but just don't have the time to do it consistently enough to be fully on top of it. They have a few days vacation and go do a nice destination and expect to jump right back in at the same level they have done before, or even worse they buy some new gear as if gear makes up for practice. Like with a lot of things, there is no substitute for time in the water as a diver. Good decision making and technique come from lots of consistent practice, that most people don't have the time to do.


Isn't that exact same thing that is happening in anything touristy? And I fail to see why it is wrong? (Except drunk sleeep deprived guide).


If you really have only a vague recollection of basic safety checks you shouldn't be diving - seriously.


You should, according to PADI norms, be offered a refresher dive. It costs $10 more and you spend 15 minutes with a dive master reviewing basic skills before a normal dive. The dive master also then knows to keep you close during the dive.


This is exactly what the resorts I've been to do. Dives are free (All inclusive, Couples Jamaica) but if don't have a dive book with a signed off dive in the last year it is 50$ for a refresher/skills test.

I've normally felt really safe on these but once there was way to many people for them all to be babysat and the group actually got split up due to 'issues' that the following guide had to help with.


Plenty of resorts and other destinations offer resort and discovery diving. You do need be 10 years old, but no prior experience needed, after some basics some places let you do 1-2 open water dives in the same day! All equip is provided. You really DO NOT configure any of your stuff on these dives (you do get comfortable breathing underwater). It's a scuba dive "experience".

Unless you are a diver please don't comment with this type of snark - seriously.

" Discover Scuba Diving is a quick and easy introduction to what it takes to explore the underwater world. To sign up for a PADI Discover Scuba Diving experience, you must be at least 10 years old. No prior experience with scuba diving is necessary, but you need to be in reasonable physical health. Are you ready to try it out? "


Resort Diving is mostly safe, the dive profile helps keep you safe. At 30ft, a lot less can go wrong. You can easily survive a rapid ascent from 30ft, heck you likely don't need to actively blow bubbles unless you took a huge breath or are ascending super fast. OP who hasn't dove in a while shouldn't make their first dive on vacation a 120ft bottom. They will likely not remember how to breath, how to swim and will consume too much air and blow the dive for everyone. I refuse to dive with strangers on dive boats, I have never once had a dive buddy physically verify my secondary and some of them get weird when I ask them to verify their primary and secondary with me. The 'I know' eye rolls when i show them where my weight release is, where things are on my BC. Honestly thats what pushed me in to technical diving, everyone takes it serious. If we do our math wrong and the drop tanks aren't sufficient or if the trimix was off we were all dead. When we did cave dives, knowing each exit, knowing the routes we were going to navigate. Rehearsing the transitions between lines. Even with the best planning, things go wrong. Read up on the Diepolder II and III caves - scary stuff


Seems to me that cave diving is like climbing 8000m mountains. Death is a realistic outcome no matter how good you are.


What instructors and dive-masters actually do (or should / are trained to do) for those dives is hold onto the first stage regulator at the top of the tank for the entire duration of the dive and never pass 12 meters. The diver never even needs to worry about buoyancy. We use to call them Lipton (tea) dives, because it was just dipping tourists into the water ;) They are absolutely 100% safe when done according to the requirements.


12 meters would have been "deep" where I was :)

I called them "disco" dives. Dive down a bit, show them some lights and some fish turn around a few times and back up. A play on the discovery label.

But yeah, the grumpy "master" divers will be yelling at you from shore about the whole thing!

Def want 100% contact from start to finish, and if you keep dive to 8-10 meters or less (hard bottom) helps. Just throw some statues / structures down there to look at.

Things to watch for. Folks who can't equalize - just come up or do a super shallow route if you can. And def need to make sure folks can breathe comfortably underwater (shallow water / cow pen). Also doesn't need to be long, it's about the experience. Some idiots take advantage of the depth to extend time which is silly.

Another labor was resort dive, but wasn't sure what differences / similarities were between all these experiences.


"Unless you are a diver please don't comment with this type of snark - seriously."

PADI Advanced, deep, nitrox, 100+ dives mostly in the cold waters of the North Sea.

Edited: added context


Absolutely, I am a somewhat experienced diver looking at certifications, but it's all too easy to forget things even if you have more than a vague recollection. Whenever I haven't dived for a couple years, I always ask an instructor to check on me while I prepare for the first dive, because I just don't trust myself.

A dive or two later I am okay with helping newly certified divers both on shore and on the boat, but on the first dive after some time you should never overestimate your memory.

Diving is safe if you know how to keep it safe.


> it's all too easy to forget things even if you have more than a vague recollection. Whenever I haven't dived for a couple years, I always ask an instructor to check on me while I prepare for the first dive, because I just don't trust myself.

Do you have a checklist?


If you mean something to go through physically (e.g. on paper) no, at least not for non-technical dives. There is a standard list of things to do, which I agree with the parent comment you should remember more than vaguely before diving.


Here is the recommended pre-dive checklist.

https://gue.com/blog/the-gue-pre-dive-sequence/


In Israel a short refresher course is mandatory if you haven't dived for six months. IMO any reputable company should require the same.


This should be mandatory for a lot of sports, honestly. Assisted climbing (lead, top-roping) comes to mind. Kinda crazy that in many gyms you can get on a wall with no verification that your belay knows what they're doing.


As far as I know they're mandatory everywhere, but pretty much noone checks this. If you don't sign up yourself, it's not happening.


Doesn't sound like the evidence backs this assertion, irrespective of your experience.


What evidence? Evidence that lots of diving places take safety shortcuts?

I myself got my first certifications with two amazing divers, they taught me very well and I had a lot of fun. However they also allowed people to take dives that they weren't certified for, because it was a small diving center they could only do two dives a day and they had to satisfy a wide range of divers.

They did that with people that they had taught and knew well, and never had issues (certainly not a 60m compressed air dive as in the article!) but it did indeed make diving somewhat less safe.


Well, presumably if OP statement were true, recreational diving would involve large numbers of casualties. Casualties in recreational diving are somewhat rare, however, at 2 per million dives.

Tourist dives are even safer since they do not perform advanced dives. Overall, the evidence does not support the view "If you really have only a vague recollection of basic safety checks you shouldn't be diving - seriously."

Most tourists diving have only that and they're not dying in droves.


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.


or using Tesla cars in autopilot mode as an equivalent to a self-driving car.


How many of those tourists will die as a result of this? The data seems to suggest it’s vanishingly small.


Exactly. Yes, cave diving is extremely dangerous. Deep diving also is dangerous. But there are dives, amazingly beautiful dives, that, while not devoid of risk, are very safe. Simple, shallow dives in the Caribbean, for example, where the benefit of the tank over snorkeling is just that you can stay down longer.

Diving is wonderful. Get certified (but you don't have to be for some dives).

I also sail. Also wonderful. Can be dangerous if you push the edge, but more likely embarrassing if you stay within your limits.


I don’t know the stats but from what I read a lot of accidents are not tourists but more serious divers who go below 20-30 meters. I haven’t heard about people getting injured while on regular tourist dives.

Same with motorcycle riding or paragliding: it gets dangerous once you are beyond the beginner stage.

I really don’t know what could go wrong on the typical tourist dive if the dive master keeps an eye on people and you don’t panic.


That tracks with what I've heard, anecdotally. Accidents happen when people plan their own dives, go alone, push too far out of their comfort zone, or dive in conditions they aren't prepared for. These things are risk and consequence multipliers.


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 dangerous dive site, but its popularity attracts the most cocksure types trying to prove something. The main attraction at the blue hole is the arch. It's a 40 meter archway who's apex is at 56 meters and leads from the cylindrical blue hole out into "the blue", where depths are insane and theres nothing but water anywhere you look. It's very beautiful, especially while the sun is rising, as it faces East. 56 meters is not particularly deep, but it's deep enough for any beginner and even most advanced divers to get seriously narced (drunk on nitrogen). It's also _just about_ deep enough for the partial pressure of oxygen to reach a critical point where oxygen becomes toxic. When it does, your muscles try to burn off the excess oxygen and you temporarily lose control of them, they shake, so your chin and cheeks start to twitch and you can easily drop your regulator. When the twitching is over, you involuntarily take a deep breath...

If you're an experienced diver, know your narcosis limits, know your oxygen toxicity limits, know your air consumption, havn't had a drink the night before, and are physically fit, maybe you can pull it off without trimix. Otherwise, it's an absolute beginner's dive with the right gas blend.


There's a short documentary about it on youtube where (IIRC) they claim most of the fatalities are people who try to swim through the arch on a single standard aluminum 80 tank.


A divemaster once told me that the best training he ever had for recreational diving was doing a technical diving course, because knowing your limits was no longer something optional.

The written test for open-water felt inadequate to me; I expect most reasonably smart people could pass it without any study, what with only needing 75% on multiple choice.


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.


That's mostly correct but your body doesn't metabolize oxygen based on the partial pressure. The actual rate of oxygen metabolism depends mostly on activity level regardless of depth or PPO2.

Your body can function pretty well at PPO2 levels less than 0.17 bar. People go to an altitude of 10000 ft / 3000 m all the time where PPO2 is only 0.14 bar.


0.17 is a rule of thumb we use in diving. There are many like it which allow a little leeway in case there's a slip-up. pp02 can surely go higher than 1.2 (I know personally) before causing problems in some people. That said, I bet if you're climbing at 0.14 bar that you've stashed a pony bottle of 100% oxygen somewhere in your kit, just in case, no ?


People live and work just fine at 0.14 bar PPO2, no supplemental oxygen required. Aerobic capacity will be reduced. 10000 ft is the usual limit for requiring supplemental oxygen in aviation.


Thank you for sharing your experience. It sounds like a fascinating subject.


Trimix is a different breathing gas mixture with added helium, to avoid the mentioned problems with too much nitrogen and too much oxygen.


Diving seems like one of the recreational activities where it is easy to end up doing something much riskier than you intended (another I'd say is alpine hiking):

1. Being able to easily sign up for a dive at an all-inclusive resort makes it seem more 'fine', you get a false sense of security that you will be taken care of.

2. Dive shops tend to be fairly relaxed with checking if someone is properly qualified to go on a particular dive. They barely check your papers or equipment, if at all.

3. You often don't really know what exactly you are getting into until you are in the middle of it. And then it can be too late to bail. Is it safer to abandon a group and attempt to go back and potentially get lost, or go into an environment that looks more dangerous than you expected?

I am a PADI open water diver, but only dive a few times a year, so not too experienced. One time I signed up for a shipwreck dive at an all-inclusive resort. I am usually quite careful, and naively thought it would be fine - we just dive down, go around the wreck and come back up. I rented all equipment, and had to pay extra for a wetsuit - the 'default' was to just go in my swimming trunks. Turned out, on the dive we ended up going inside the wreck through a very narrow passage under it, going through narrow dark corridors surrounded by rusted metal. Touch anything and you get scratched (which I did). Your cables or tank can easily get caught (which it briefly did for me - and since I was the last one in the group it was quite scary seeing the group getting away from me as I tried to catch up). The current around the wreck was quite strong.

Somehow the dive was planned such that there was very little allowance for extra air. I ended up using more air than I suppose was normal, and there would not have been enough to make a normal ascent. I ended up having to use the dive instructor's alt supply for some of the return swim and switch to my own for the safety stop, otherwise I would've run out. It is one thing to practice it, and another to actually have to do it on what was supposed to be a relaxing 'touristy' dive.

On another occasion, a dive instructor took me and my partner (who was on an introductory dive - she doesn't have a license) into a cave, which is also more dangerous than I would've preferred.

These experiences - combined with the general experience of wasting the whole day on a rocky boat breathing diesel fumes for an hour or so of diving - make me reluctant to dive again, unless the sight is particularly picturesque.


Am certain if you ask 100 beginner divers, 99 will have their own brush with death adventures!

Mine came in the form of a six foot barracuda getting a bit too close for comfort. I am sure if I hadn't played it cool. Had somehow attacked or acted aggressively to shush it away (when I was a guest in it's deep sea domain). It would have enjoyed a nice lunch of fresh human flesh.

The second was going below the hard deck at 300 feet whilst diving the continental shelf in the Caribbean. It's stunning. Floating weightlessly over the void that drops suddenly over a mile in depth. Feeling the rush of frigid current rise from the abyss. And seeing mysterious shapes as light filters down into darkness. But I too ran low on air. And had to come up fast.

I haven't been diving in decades. And would require re-certification. But I've always heard legendary tales of the Red Sea and Australia's Coral Reef. Definite bucket list items ;)

https://oceana.org/


I've done a few hundred dives (so, intermediate? with some additional certifications for deep/nitrox/rescue/divemaster) and the biggest problems I've had were 1) dropping a steel cylinder on my toe on a boat 2) getting sunburned on my scalp before I started wearing a hood even in warm water, due to an extended surface interval 3) dodgy food on a liveaboard.

I don't think most recreational divers push things close to the line at all.


Most definitely misremembering the depths! 300' begins to collapse lung & heart cavities ;)


The issue with depth is 1) you can't do a direct ascent to the surface past...18m or so?...with a high level of safety, for a large number of users, and from 30m or so (the recreational limit for most programs) it's even harder, plus that's the upper bound where nitrogen narcosis starts to set in. I've done down to 40m on air which is the next limit and the point where a lot of people have more serious nitrogen narcosis. Beyond that you really should be doing decompression diving and start to be looking at different gas mixes which makes it all a lot more complex. At depths beyond >50m oxygen toxicity on air would be bad too. The current normal limit is ~56m on air, previously people have done 60-65m pretty consistently on air, and the record is probably 155m (but that is insane and almost certainly caused harm, plus had high risk).

Ascent from depth without having cavities open to equalize pressure will be a really bad deal even from 18m (and really from comparatively shallow depths like 3-6m), but that really just means breathing out at slow rate during ascent. For that it'd be explode vs. implode though :)


Scuba diving is done at ambient pressure. Lung and heart cavities don't collapse.

(Lungs do compress during breath hold freediving.)


I'm no marine biologist but you can be certain that humans are not a regular diet of barracudas.

Once, a 5-meter tiger shark came to me out of the blue and got too close, but as humans aren't a regular diet of tiger sharks either, it swam away.


I've met literally dozens of people who talk about their close brush with a barracuda while diving.

They are a minimal threat but they look kind of scary so people always always think that they had a close call with one when the barracuda is just doing what they do which is checking out a human who might hand them a fish.

It always makes me chuckle because I hear people tell their barracudas stories and they always sound the exact same. At no point were they in any danger but they really think they were.


Just like masses being overscared with sharks because of Jaws, its probably because another but much less popular movie “The Depth [1977]” with Nick Noltie where in a final scene Noltie wins underwater battle because he knows where huge Murena lives and put a villain head in there. Then we see that Murena litterally sicking him into her hole with a force that break his mask and break him in half. Definitely one of the most memorable scenes of the movie and definitely what made me start my doving adventure (now cerified with CMAS and PAID up to deep dive / rescue diver). Definitiely movie worth rewatching.


Barracudas can freak you out because they seem to be curious. They just hang out and watch you. The only time I've heard of someone getting bitten was on a YouTube sailing channel where the group was making fun of one of the crew for being the only known human to actually be bit by a barracuda. IIRC he was messing with it.

Jelly fish, OTOH, suck.


Barracudas really aren't dangerous to divers. There are a few recorded cases of bites but I don't think anyone has been killed.


I've read they sometimes bite because of flashing jewelry which they mistake for shiny small fish.


When on a snorkel trip in the Florida Keys I was told not to point at the barracuda, because tourist often fed them hotdogs to get a close up look, and so they were trained to eat anything hotdog shaped... no idea if it was true.


If the Great Barrier Reef is on your bucket list then you really want to get on that asap. It's getting more and more bleached.


Yep. Sadly, I'd say that even now you might want to spend your travel dollars elsewhere.


I'm very curious what gas blend were you using at 300 ft - I'm fairly sure that would be fatal on air or even nitrox.

I'm also shocked that you could come up from that depth with any sort of urgency and not be seriously injured / killed by some form of DCS.

Maybe I misunderstood and you were not a beginner, because otherwise that tour operator has no business running a dive op.


Nitrox is 100% fatal at depths beyond prescribed limit. The whole point of Nitrox is to increases the oxygen content in the gas to minimize nitrogen absorption. A side effect of this is that you will get to hyperoxic poisoning thresholds earlier on a deeper dive profile. This is why Nitrox requires additional certifications, to help understand these limitations and learn how to calculate your max operating depth. (when using nitrox wihtin these thresholds I find I have more energy at the end of my dive).

To go deeper you need to blend in inert gasses and decrease o2 and n2 to keep partial pressures below fatal doses. This means most commonly mixing in Helium to cut down on over o2 and n2 in your gas mix. Human tissue I guess doesn't absorb helium the same way it does n2.

Source: Open Water Scuba Instructor with multiple agencies... I havent taught in about 5 years though so some of this information may have changed, especially in light that global helium shortages (or US stock piles?) may have driven the price of He up to high to be used for mixed gas diving.


We still use helium for mixed gas diving but it is more expensive now. Human tissue does absorb helium in much the same way as nitrogen (or any other inert gas). The rate of diffusion is a little different which can impact the decompression profile.


You can see the coral reef in Eilat (Israel) without really diving since it is in shallow water, not sure if it is as good as in Egypt but at least there is a decent hospital near by if something goes wrong.


Yeah, I'm a beginner diver (< 15 dives) too and I've been a bit horrified just how easy and loose some of the diving centers play with safety and capability checks. Just like you said, most of them don't even check if you passed the shipwreck advanced diving cert.

You're experience matches mine so I'm now extra careful to vet all the diving centers - especially looking for complaints of divemasters being too "hardass" on people and demanding good equipment / qualifications. A lot of other divers are still surprised that my inital diving instructor actually checked if I could do the required 200m swim by demanding that I do it in the pool before starting training.

I've also bought my own equipment because of that - who knows just how well the regulators, dive computers and BCDs are maintained in those places. It's scary enough that you need to trust them with air and tank quality.


I took the basic (open water?) license in Australia, and the group were sent into a pool to tread water for 20 minutes or something. Now, I can barely swim. Really poor buoyancy and bad technique I guess, so have never really learned.

If the instructor had looked away from the TV for a second he would've seen and flunked me, which would probably have been a good thing. I'm stupid. Went through with it and out on a couple of dives which I enjoyed greatly, but now ten years later still haven't dived again and won't until I can swim. Having kids does stuff to your sense of self-preservation.


top tip: most humans can float as long as their lungs are full


Being super lean and carrying mass in large muscles will ruin this, fwiw.

In my late 20s I was militantly fit and also very into rock climbing. I supplemented this with some lifting to balance things out; people who ONLY climb end up looking a little weird as the lats develop out of proportion with the rest of you.

Anyway, even with a lungful of air, my neutral buoyancy point was like 8-12" below the surface.

Alas, I am now 51.


Same here when I was younger (i.e., less fat). With a full breath of air in me, I'd float, but exhale a bit and I could sink to the bottom of a 12 ft pool without any effort on my part.


Only if they're not panicking and thrashing about.


true. it’s definitely easier said than done, but it’s a useful fact to have in your head


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 boat. It's obviously our fault for not being safe but we definitely didn't have the necessary fear in us for our skill level.

I think PADI should be emphasizing that your first 20 dives or so should be with a guide never exceeding 60ft. IIRC, a lot of the course material for Open Water is about shore diving with a buddy by yourselves.


> As a PADI Open Water Diver, you'll be trained to a maximum depth of 18 metres/60 feet, and are qualified to dive in conditions as good as, or better than, those in which you trained

ref: https://www.padi.com/courses/open-water-diver

PADI does emphasize that with an open water cert you must absolutely always remain above 60ft.

That’s what’s shocking to me the most about the article and some of the conversation here—many folks are talking about diving to crazy depths as if that’s normal.

I don’t know why that is, but I will agree with your general point as a result. Folks need to understand this is a dangerous sport and one that can easily kill you (though not by barracuda).


I'm just learning that I don't actually know PADI Open Water guidelines despite > 100 dives. I guess that syncs with my experience that Open Water cert doesn't necessarily actually train you.

I'm like genuinely confused at this point. I've had so many guides, even in places like Hawaii, not follow their own guidelines. It would be trivial for PADI to see Open Water divers are diving the thresher sharks at Malapascua, for example, and that would necessitate they go past 60ft.


The thing is, it's actually extremely easy to get an Advanced Open Water cert. I did it in a few days in Dahab, on the Sinai. We actually dove the Blue Hole as our last dive.


Yeah, that's crazy too. Maybe I have rose colored lenses because I did my advanced open water through my university and we did tons of dives to the same spot with I guess more academically focused exams and whatnot.

Still, that was circa 1997 so, um, I forgot pretty much all the detail :).


It's obviously our fault for not being safe but we definitely didn't have the necessary fear in us for our skill level.

I think fear is what has kept me safe this long. I've got at least 100 dives under my belt but I was quite careful to slowly ramp up the difficulty, and even now, I'm very cautious of really strong currents.

I must have done over 20 easy shore dives just getting navigation experience (and I'm still not super confident with it) before jumping on a boat to go deeper. And even then there were a couple of potentially close calls. I must have had over 40 dives before I even went on a dive holiday, and many of the scenic places are not super difficult to dive.


> I was quite careful to slowly ramp up the difficulty, and even now, I'm very cautious of really strong currents.

This is most definitely how it should go.

It seems like an inevitability you will eventually have something go wrong (maybe you lose your group, your mask is a problem, you burn through air too quickly, etc). In this scenario the most important skill is to not panic and control your breathing but I think that mostly comes with experience.

While you develop experience, diving conservatively hedges against some of the worst case scenarios. Something as simple as a mask coming off can lead to panic which leads to hyperventilating. Someone hyperventilating will feel like they just can't get enough air and the immediate reaction will be to exit as quickly as possible.

Guides, as OP points out, should be far more sensitive to the experience a person has.


I was sixteen when I first started diving. It was only after I first (briefly) lost track of the dive group, at night, that I realized I had absolutely no plan for what to do if I was disconnected from the guide. (At night.) This possibility hadn’t been discussed, at all.


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, and I'm worried I will make a mistake...


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.


The two biggest things with alpine hiking are probably weather and not turning around when you should. (I could probably add just being grossly ill-prepared like lacking map and compass and perhaps depending too much on electronic gizmos.)

Over the holidays I was reading a book about a winter fatality on Mount Washington a few years back. The person was actually very well-prepared and fit. And even had some big mountain experience--but always with guides. And simply went out on a day she should never have been out on.


Trails in the Alps in Germany or Austria can be tricky precisely because they are fairly well marked and signposted. A red route can be a 'walk in the park', nicely trodden path with a steep gradient in places, or include bits that are quite exposed with a danger of falling. As a complete amateur, it is easy to end up on a riskier route than you expected, as it would not even look remotely risky until you are half-way through. And then you encounter some dodgy bit, it can be hard to decide - do you turn back, or do you attempt it? Will it get worse or better after this?

One should be vigilant not to get lulled into a false sense of security and prepare well for any hike. I have been irresponsible in the past at times but now I know better - I wish I did back then too.


Yep, this literally just happened to me here in Switzerland. An "easy" route at around 2300m which was great - a nice wide, cleaned road around snowy areas. And then suddenly a steep descent with 30+ cm of frozen iced snow. Without proper equipment, that would be extremely dangerous and even with equipment is was far outside the comfort zone.


Ice can be particularly tricky. One of the nice things about modern traction gear is that it's easy and light to toss in a pack "just in case." That said, with harder ice and steeper terrain, it's not a replacement for more specialized gear.

I tried to do one hike this winter that wasn't even particularly hard but it was really icy and cold and the steep parts were steep enough. I ended up turning around given that I wasn't wearing my full crampons.


I turned around at Bright Angel in the Grand Canyon this Winter. Despite being real bummed about it, I headed down Hermit's Rest which gets more sun and was no longer icy.

"Oh well, I'll settle today" I thought. Midway down Hermit's Rest I cross a much more experienced hiker -- she had lived in and around the Grand Canyon full-time for a year. She was only coming back to the Rim to move her car due to the incoming on-season (yeah, just a "casual" river to rim and back, lol). She told me she had just been around Bright Angel the day prior and had seen a girl be air-lifted away with a broken leg. Even though she had microspikes and months of winter experience in that park specifically, she bailed.

Suddenly, I didn't feel like I settled anymore... turning back can save lives and limbs. The majority of the time, nature (and the trail) will still be there when you return. It will certainly outlast you, if anything.


For those who don't know, there are signs around the "presidential" peaks in the White Mountains that say:

> The area ahead has the worst weather in America. Many have died of exposure even in the summer. Turn back _now_ if the weather is bad.

https://www.reddit.com/r/ScarySigns/comments/ekx3rw/found_wh...

They are NOT kidding. Things can go from beautiful to ugly very quickly. 5,000 feet might seem like a joke to somebody from out west, but it's not all smooth trails (practically the same as pavement) with plenty of switchbacks like you're used to. When you're on steep nasty almost-technical terrain and its wet and hella windy, safety can suddenly be a long way away.

I know those mountains very well, I'm a strong hiker even by local standards, and I still make sure to exercise plenty of caution every time. Those rocks are not to be trifled with.


Based on the comment about the electronics, GP is likely referring to Kate Matrosova, who perished in positively appalling conditions, even by the very low standards of winter in the Whites.

She died just off the Star Lake Trail, having ascended to the ridge via the Valley Way, which hits the ridge line at Madison Hut (4800', or much lower than the summit of Washington at 6288'). My partner and I have bailed off pretty much exactly her route in the summer when the winds were too high for our experience and fitness levels when we popped up out of the lee side of the ridge line on Adams.

Anybody who wants a really well researched case study should read Ty Gagne's book on her trip and the subsequent rescue attempt.

Incidentally, my partner and I climbed Washington on a guided trip the weekend after she died. The weather was so good the guides had their cameras out to take pictures. The extremes in the Presidentials are no joke, as stated, but can also result in some beautiful days.


Yeah, that's the case and the book I was talking about.

The actual accident, while obviously very tragic, wasn't especially interesting. Basically don't try to do a Presidential Traverse during the worst weather in about 20 years. It was actually a different situation from the more common cascading failures mode of accidents.

She made a grave error by deciding to drive up to NH that weekend and a fatal one by continuing above treeline. Even Rick Wilcox (owns local climbing gear/guide store and has summitted Everest) basically says in the book that she was well enough prepared but shouldn't have been out that day.

That said there were definitely lessons around just because you have a lot of experience, don't assume you understand the local situation when you have little to no experience there.

But the search and rescue account was morbidly fascinating. Also demonstrates that locator beacons won't always save you. (She admittedly didn't use it properly but I doubt it would have made a difference given the weather.)


I think the big takeaways for my partner and I were a little more nuanced. With all respect to Kate Matrosova and acknowledging that we don't have any knowledge of her thoughts that day:

0) Her mileage to the top of Madison was off by about a mile on her written plan. Not a good place to start for an ambitious day.

1) Most of her prior experience was guided where somebody else was responsible for making the decisions. I am fully prepared to believe that she had the physical experience, but would suspect that she lacked the decision-making experience that would have saved her.

2) She died heartbreakingly close to Madison Hut. If she'd turned around 30 to 60 minutes earlier, she might have made it to the relative shelter of the hut with enough energy left to warm up and get back below treeline on the Valley Way, which is quite close to the hut. Speculation, I know, but I can't help but wonder.

We talked a lot about the decision-making because we could both see ourselves having a go in the same circumstances owing to our inexperience (we independently thru-hiked the AT, but we aren't mountaineers). Reading it was a really useful case study for us and helped think through identifying when we're about to cross the line from adventure to peril.

If you didn't know, he's got a second book out, btw. Gonna crack it open next :-)


I know he has another book out which wasn’t available when I bought this one. I’m actually involved with a winter hiking program which is how I found out about this one because I’m usually involved with leading winter trips in New England.

To your point, I agree and think I touch on most of them upthread. Weather is definitely an an important consideration. She hadn't mostly been involved in making tough calls.

And, yeah, she had opportunities to bail after driving up from NY. But clearly she wasn't going to do that prior to seriously going for Adams at which point it was too late given the weather.


BTW, when I said "you" before I didn't mean you @ghaff. I know you know these things; that was for the majority of HN folks whose experience is likely to be with taller but still less dangerous peaks. I apologize for the lack of clarity.


> And even had some big mountain experience

One problem is that that experience lull you into a false sense of security. I'm not talking arrogance or so. Merely that you can do something everyday that's unsafe and get away with it, training you on bad data to think it's safe.

Like avalanches. Certain conditions are met. You go out. Everything is fine. Same the other times. You learn that it's safe. Suddenly an avalanche happen with those exact conditions. It was just arbitrary it didn't happen the other times.


Avalanches are probably one of those things that you can reduce the danger of in various ways but probably can't avoid entirely other than avoiding mountains that can potentially have an avalanche entirely.

For all the mitigation work they do on a regular basis, there are periodic avalanches at ski areas in the Alps and in the US West. Many of these are out of bounds, but not all. [1]

[1] https://www.powder.com/stories/skier-killed-in-avalanche-at-...


Yeah. Like when in a group having to traverse something almost horizontally on skis, we go with a long distance between each other. So that the risk of triggering something is smaller, and if something is triggered as few as possible is involved and others can do the rescue. I also have beacon, back pack with airbag etc. So minimized the risk as much as I can.

But sometimes I think. If I have to do aaall those things to mitigate the risk, is it really safe and worth it? So far, the answer is yes. Maybe it changes if I ever see an accident.


As a native of a very well known mountainous state I can say it's more than that. If you're summitting on a mountain you need to be prepared to bivouac at least one if not two nights and survive adverse weather. Even experienced hikers can find themselves trapped far from the trailhead by either weather or fire. That's not even talking about the usual bears, mountain lions (don't hike alone), or ticks (Lyme Disease is real).


Landslides & avalanches would be the other big worry and not just from them coming down on you from above. It's not unusual for trails some places to cross a couple hundred feet up scree slopes that are right at the angle of repose. A bad slide can start just from standing still too long. I've been in groups that had to run across them and afterward we questioned whether we'd been stupid to even try.


Not a diver myself but my best friend is (he is also an instructor as well as cave/shipwreck diver and he has also worked for a dive center with a lot of tourists). I remember him telling me that diving in shipwrecks(or caves) requires additional certification, so I assume that those who have only the first/second star were not allowed to join (especially in a trip by an all-inclusive resort).

What you describe sounds like a terrible and irresponsible trip to me.


> What you describe sounds like a terrible and irresponsible trip to me.

That is typical of tours and resorts. These are not in the US where the law might investigate. Just some divers who will show anyone around. Many will teach you to dive, a two hour course is enough for a simple dive (ie.something you could snorkel to), then they take you on a first dive that needs far more training.


In the US there typically won't be a legal investigation unless someone suffers a serious injury or death. And even then it will typically be handled as just a civil issue (wrongful death lawsuit and insurance claim).


Probably, I'm not into diving so I can just report what I've observed from my friends who are. Though insurance in the US tends to be stricter about what they allow.


Both caves and shipwrecks are allowed with Open Water as long as you are within a certain distance from an opening and natural light.


Any place with Hard Ceiling (something between you and the surface except water) necessitates specialty training in most dive certification organizations.

The issue that many take with PADI is that their values are mostly aligned with making profits.


my dad always called it Put Another Dollar In


It's commonly known as Pay And Dive In here in the UK.


I’m from the UK too. Clearly a common theme


Absolutely not:

> You need to be PADI Advanced Open Water Diver who is at least 18 years old to enroll in the Cavern Diver course.

https://www.padi.com/courses/cavern-diver


Edit: I was wrong with the above statement.

After doing some research around this. Cenotes are an exception to the rule and even though Open Water Divers often do enter inner rooms in wreck dives and caverns what matters is maintaining a direct line of ascent.

---- Original ----

Open Water can do caverns. Dos Ojos is incredibly popular and has hard ceiling.

Edit: Also Cavern Diver is just a specialty cert and doesn't confer any extra penetration. Those certs are mostly designed for skill mastery. IANTD's Cavern cert is required to get Full Cave, but I don't know if PADI's would count towards it.

https://blog.padi.com/2019/04/29/must-dive-cenotes-for-open-...


Did you read your own link?

> certified Open Water Divers can take a cavern tour guided by professionals qualified by some of the cave diver training organizations to lead such tours. This is a highly controlled, limited tour along a line into the cavern zone, which is defined as within the natural light zone and within 130 to 200 ft (39-60m) (some minor variations here) of the surface.


Yes, I read my own link. OP was talking about a guided tour.


The case in point is what you said: "Both caves and shipwrecks are allowed with Open Water".

As a rule, they absolutely aren't.

In this specific place, PADI allows some of them to make a supervised dive at a certain site following a specially installed line. This doesn't change the rule, which is "Open Water Diver certification does not qualify you to dive on shipwrecks, nor caves".

At some other place, there may be an option for a person with Open Water certificate to drive a semi-trailer truck, while under supervision from a trained professional, and over a course specifically crafted to minimize any possible collision. This doesn't change the rule, which is "Open Water Diver certification does not qualify you to drive semi-trailer trucks."


After looking into this, I'm wrong and I'm going to edit my original comment. My apologies.

Where I'm confused is the difference between a direct line of ascent (even when there is an overhead directly above) versus penetrating beyond that. This is a differentiator that makes swim-throughs OK but most caverns not OK.

Edit: Turns out I can't edit a comment that old.


If the dive is appropriate for your cert, responsibility falls down to yourself and your buddy if he has a higher cert. If the dive is not within your cert. level, responsibility goes to the instructor (if he went with you) or the sailor that drove you. When in doubt, check local law. That's for negligence. Then it's up to your insurance to fight / cover for damages.

Always dive within your limits, and if interested find a local club. To me, dive turism is something that can only be truly enjoyed after reaching a certain dive level. It's no fun to see turtles or sharks if your whole focus is still on being neutral buoyant or checking your air supply.

As you say, diving is like hiking. I love hiking, but I know my limits and will not attempt a K7 or travel with a specific hike in mind. I like walking a trail, seeing birds and views and nature. Same applies underwater! The red sea is amazing, but so can be your nearest dive site.

If truly afraid / curious about things that go awry, "Diver down" is a nice intro


Yes we do. I have some 30-40 dives done with Advanced open water diving license, but since I only dive in exotic places 1-2 we visit times a year, I always need a full refresh as first dive on every vacation. Not having any scuba equipment at home, the things life all safety and equipment checks, even though easy, just fade from my memory.

I recall, when doing my first real dive (not training in 4m), in Croatia, the instructor took us to 33m. I was showing him this on depth meter, he just signaled OK with fingers. The feeling of being so deep that we didn't see surface anymore, on a first dive was a bit unnerving.

I also have similar experience to yours with shipwreck, although with some 30 dives it wasn't so scary. But we were swimming through narrow passages of very old shipwreck from WWII on Bali, and I felt how tubes are touching the walls. It wasn't a big wreck, but I wouldn't go to this kind of inspection on my own, just followed instructor.

One thing I noticed - a minority of folks are so arrogant they barely follow instructor and do what they want, ie not following the group, swimming lower than instructor etc. Can't comprehend this, I mean you are literally reminded by all senses how you are in very unfamiliar environment, yet some can't show any respect for it, even though they don't have much experience themselves.

Anyway, a very cool sport, although its one way to realize how messed up our environment is, when you see more and more corals dying literally just over few years.


I had a similar experience at a tourist destination island in Australia. We went on a dive with just a couple of meters of visibility, with a big group holding on to a anchor chain. I couldn't see the dive instructor and I couldn't equalise my ears. Everyone kept going and I basically just stopped at about 10 meters down. It just wasn't worth it, especially given the ear pain I had for weeks afterwards.

As a counterpoint, I did another "introductory" dive at another Australian island a few years later, and it was beyond amazing. Prettier than any wildlife documentary I had ever seen. Incredibly attentive, patient, and professional staff, etc...


Would you care to share where the good and bad experiences in AU were?


Bad was Great Keppel Island. Basically it was a bunch of drunk 20-something-year-olds doing "activities" like diving, getting plastered with overpriced drinks, and unsuccessfully hitting on each other. The coral was half dead from bleaching, and the other half was torn up by boat anchors.

Good was Lord Howe Island, which is the last true paradise on Earth. It's on the southernmost tip of the Great Barrier Reef, so it has coral, but none has bleached. The waters are pristine and protected. It's a place more civilised than Japan. You can leave a camera bag with $10K of gear in it on the beach and go on a hike, because it will be there when you get back. There's a beach with a shack next to it where you can stuff a $20 bill into a jar to rent snorkelling equipment. The jar had about $500 in it. Nobody is going to take that either. This place is what most places should be like, but aren't.

The dive at Lord Howe Island was just... unspeakably beautiful. To set the scene: the missus had done a dive before (supposedly), and this was an introductory dive anyway to a depth no greater than about 12m, but she had a panic attack. While the instructor was patiently helping her relax, I snorkelled around the boat. Above were thousands of wheeling seabirds coming in to roost to a cliff about 100m high. That view alone was spectacular. Below were layers of coral and shoals of fish like underwater highways of colour. Had I paid the fee just to see this I would have considered it money well spent.

Then the younger instructor leading the team of kids doing their PADI certification offered to take me on a one-on-one dive since a boy in his group used his air too quick and we had spare time now. I got to see shellfish bigger than I had ever seen, a huge octopus squirt ink in the instructor's face, then we dove through a tunnel under coral, there were fish bigger than me, and generally it was just awesome.

I highly, highly recommend this place to everyone who's willing to listen and has the budget. My tip is: skimp on the accommodation, splurge on the restaurants. Go there to turn your phone off and relax.


Thanks for the in-depth response, much appreciated! Turns out Lord Howe Island was actually on my partner's bucket list. I definitely bumped it up a bit more now.


For any beginning divers reading this, dive your limits.

I am an instructor and it always makes me sad to hear about people questioning the hobby because of shady dive centers.

Do not let a guide or instructor talk you into exceeding your certification limits.

Also, if anyone encounters a situation like what is described above please report it to PADI asap. PADI takes cases like this very seriously and will initiate an investigation immediately.

You might save someones life.


> Dive shops tend to be fairly relaxed with checking if someone is properly qualified to go on a particular dive. They barely check your papers or equipment, if at all.

I find this is very destination dependent.

I did some Cenotes dives in Mexico that I was seriously underqualified for, and some deeper wreck dives in the Carribean too.

OTOH in Australia everything was very much by the book. The new book, even (when I qualified for PADI Open Water in the early 90s we did deep-diving as part of the training, and were qualified up to 30m, but sometime in the 00s AFAICT things changed and O/W people are these days confined to 18m or less.)

Which reminds me, I must get my 'advanced' at some point soon. I did a deep-dive specialty a while back so that I could do some more interesting reef dives at the great barrier reef, and an enriched air qualification as well, but not the advanced O/W.

One day, after many years, I may even have the qualifications to do those dives I did many years ago... Thankfully I was young and stupid enough to just go with it and enjoy it at the time.


I'm on a similar level of experience as you. I've dived a bit below the depth I'm officially cleared for, and through short tunnels. Both felt fine and responsible. But going into a rusty wreck with insufficient air and strong current is insane. I hope you wrote a review to warn others.


I dived the Blue Hole in Belize and was shocked by the slack attitude of most of the other divers on the boat. I'd just completed my Advanced Open Water (with a deep dive) so was very conscious of the regular air checks, however despite a detailed dive briefing with emphasis on the pressure cut offs at each depth, about half the party ended up having to be given supplemental air at the final safety stop. Although I'm sure that there are many irresponsible dive operators out there, there are clearly also divers (many of whom were at least experienced enough to bring their own equipment) who don't take responsibility for their own safety. I don't know if that's a training issue, or just a human stupidity issue.


I am risk averse, first time I dived it was exactly because how nonchalant way it was advertised. It was an intro to diving course, so it didn’t require any class work. We went straight in the boat, instructor gave basic instructions as we were boating to dive site. Because how it was presented I also didn’t realize how dangerous it is. Only thing they emphasized was to not fly for next 24 hours. Had I knew the real dangers when diving, I probably would have skipped it.

Not saying that it is the right way but dive shops would have a lot fewer customers if they really emphasized the dangers.

Also diving is one of the best the best experiences of my life. It really feels like being in another world. It is extremely peaceful and meditative. You should try at least once.


>Diving seems like one of the recreational activities where it is easy to end up doing something much riskier than you intended (another I'd say is alpine hiking)

You are absolutely correct, in mountaineering risk-management you have two risks an objective an subjective.

If you do hiking, the objective risk is low (hey i am just wandering), but the subjective is often much higher then one thinks (falling rocks, rapid weather change, out of water, break you angle, no way to call emergency, aggressive mother-cows etc.).

If you plan to climb a Wall the objective risk is obvious (you can fall down, rocks break out and hit you etc), and because of that you are already aware of those risks, the chance that you calculated the subjective risks in too, is much bigger.


> These experiences - combined with the general experience of wasting the whole day on a rocky boat breathing diesel fumes for an hour or so of diving - make me reluctant to dive again, unless the sight is particularly picturesque.

In my other comment, I recommended that everyone try Scuba diving at least once, cannot edit it now but there is another option, free diving. Most of the reefs and fishes are around 30-40 feet depth. With free diving, you can experience beauty of seas without carrying heavy equipment, worrying about equipment failure, ascending too fast, etc.

I have also because of similar reasons, moved my focus on free diving. There is less overall risk in my opinion, as long as you are not pushing your limits.


"Everybody has a plan until they get punched in the face." - Mike Tyson


Not meant as pedantry, because I think it makes the quote more urgent, but it's "punched in the mouth."


Going to the red sea I had a similar experience with the guide ending up going inside a wreck with a group where many just had the continuation course after open water, through no out-of-gas situation.

It is a common discussion topic I hear among divers, and almost everyone who been diving for a while has had a similar experience. Dive guides get basically all of their income from tip, and it creates a strong incentive for them to bring guests into areas which the guest might not be qualified to be in. Same for instructors at popular resorts.

To me the whole experience was a major incentive to get better training and gear so that next time I won't be under qualified to do the dive, and the more training and equipment I get the more I realize how dangerous diving can be and how little redundancy recreational diving have. The basic premise for open water dive is that you should be able to rocket to the surface at any point, and that there is a second diver next to you at all time. Being the last person inside a wreck is neither of that.

But I will end this comment by saying that one should not let guides ruin ones enjoyment of diving. There is a lot of great diving to be done within the limits of recreational diving.


At least at my local NAUI dive shop, PADI is generally considered to play too fast and loose with the rules. Especially with new and untrained divers. The joke is PADI stands for “Put Another Dollar In”

Not that I’ll never go with a PADI dive, especially if it’s the only game in town where I’m visiting. But I generally bias towards NAUI, and would highly suggest anyone new go with a NAUI cert.


In Europe it's a very similar story, CMAS vs PADI.


Edit: I think I wasn't clear. I wasn't try to claim alpine hiking is totally safe. Just that there is less of an issue with guides taking inexperienced people beyond their competency. Clearly alpine hiking isn't totally safe as many people sadly perish doing it.

I'm not sure I agree about alpine hiking. Most of the failure states I've seen can be avoided by having at least one competent person (out too late, lost, continue in bad weather, etc.) There is still the issue of approving people who aren't fit enough, but you've got a much slower start than diving and you'll probably notice that sort of thing before you're too far in to turn back.

Edit: Possibly you meant more mountaineering-y sorts of trips instead. If you're talking about the sort of thing where you might use protection then I agree with you.


I was debating disagreeing with the equivalence with alpine hiking. As I said in another comment, it's mostly about judgment when it comes to alpine hiking. Although perhaps that’s the case with diving as well. Of course, get more into mountaineering and there are a ton of factors like avalanches you can't fully protect against. (And there's of course some overlap with winter hiking in the mountains.)

ADDED: re: fitness. I've definitely had to take people down when I've been leading a trip and even had to turn a group around. But so long as you don't push on past where it's safe, it mostly just means people don't get up the mountain. (Of course, it can be a problem with canyons.)


"Most of the failure states I've seen can be avoided by having at least one competent person"

Thats why "guides" exist. And if course it is very safe with a competent guide.

But alpine hiking can be indeed very dangerous, without.

Because Alpine hiking has climbing elements in it.

Add to that a storm and wind and fog - and you have tourists with sandals on slippery rock about to fall very deep. Happens allmost every year.


One of my (very experienced) alpine hiking instructors died after a long day summiting Rainer. His team made a rookie mistake, but it’s surprisingly easy to do when you’re exhausted and you feel as if you’re nearly done with the worst of it.


I was told, most of the climbing accidents happens in easy terrain. When also experienced people get careless.

My experience matches that.


Not sure if you are still focusing on alpine hiking or climbing.

While climbing most deadly accidents (30+% of them [1]) happen because people rappel through the end of the rope (or ropes if using half/twin ropes). Stopper knots are a 10s precaution that is often overlooked.

However, it is true that on easier climbing routes it is easier to hurt yourself because you might hit a ledge on your way down. If that happens it's most likely the belayer's fault because he/she should keep "a tight leash" on the sections just above said ledges. If you let an unexperienced person belay you I assume you evaluated the risk and are ok with that.

[1] https://www.ukclimbing.com/articles/skills/8_common_climbing...


Another point is you get much more injuries when the wall is not steep (you slide along, instead of falling in free-air), another are stones if the wall is not steep they roll along the wall. That's a perfect example off misjudge objective and subjective dangers. An overhanging wall is much less dangerous then anything else, but your brain tells something else.


I'd generally trade more little injuries sliding down a shallow wall for one big injury from a free fall.


For that you have a rope, that's the objective part...you would not climb (i hope) an overhanging wall.

>little injuries sliding down a shallow wall

Those are often not "little" the rocks rip you apart, and when you stop you look not human anymore (a bag of flesh)...happens often at glaciers too.


Oh, but in the alps there are ways with a metal ladder, where you indeed "walk" a overhanging way, without rope.

Not for everyone obviously.


You have steelropes or hooks there too and a via ferrata set with a shock-absorber and a helmet:

https://en.wikipedia.org/wiki/Via_ferrata

And if without securing...even a bigger objective danger for you to decide if you can do it, that's the point.


I'm sorry to hear that. I wasn't try to claim alpine hiking is totally safe. Just that there is less of an issue with guides taking inexperienced people beyond their competency.


I just got anxiety reading your story. Then diving it's a no for me for the rest of my life :D


I've found diving to be the least demanding "action sport" activities that I've tried, and I've done a fair bit of climbing, diving and flying gliders. Careful and well trained open water diving leaves you with plenty of safety margins in all directions. There's (well, almost) no single thing you can really screw up that would be deadly.

But of course, if the whole idea of something going wrong will leave you lying awake the night before, it's probably not worth it :)


Sorry if it put you off! For balance, diving can also be a very magical and surprisingly calm/zen-like experience. The best diving experiences I have had were in fairly shallow warm water (10-12m?) with great visibility. It is amazing seeing see-turtles, schools of fish, corals. It is like visiting a completely different world!

Basically, as long as you dive in much better conditions than what you trained/qualified for, you will have a great time. Well worth doing.

I just wish more dive shops were on the more conservative side. And that they had better boats with less fumes and less waiting around!


I totally believe you, that diving in shallow water must be amazing and not that dangerous, but now I am scared that some teacher may start there and then "obligate" you to go deeper! "Just a few more meters, everything will be fine" :)

Thanks anyway for worrying about me, ha!


Every dive is briefed on the boat. These days they will also have a website explaining the dives, the required certifications and maximum depth reached.

"A few meters more" is not dangerous per se unless you go below 24 meters (80 ft), but I agree it would be very bad to do that without the divemaster telling you before and also without him/her being a certified instructor.


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 in any direction besides the crater wall. At about 25m down, I looked up and realized we were too deep to reach the surface quickly.

That triggered my panic reaction. I started hyperventilating into my regulator, and had the urge to spit it out. But knowing that would be literal suicide, I managed to override it.

I felt like given a few minutes, there was a strong chance of getting my panic under control, but I thought, "why take the chance?" Also, the dive plan was to continue to go deeper, and if part of my panic was due to nitrogen narcosis, it was only going to get worse. It wasn't worth it for a recreational dive.

So I gestured the "up" signal to one of the instructors, and she immediately worked with me to do a controlled ascent. I spent the rest of the time doing a shallow dive along the crater wall, which was much more relaxing.


Part of your panic and narcosis was likely due to CO2 accumulation. As you go deeper and the work of breathing increases it becomes harder to clear the CO2. CO2 has a higher narcotic potential than N2.


Interesting! I don't remember learning about CO2 intoxication


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.


"A notable death was that of Yuri Lipski, a 22-year-old Russian-Israeli diving instructor on 28 April 2000 at a depth of 115 metres after an uncontrolled descent.

Lipski's body was recovered the following day by Tarek Omar, one of the world's foremost deep-water divers, at the request of Lipski's mother.

Omar says: Two days after we recovered his remains and gave [his mother] his belongings and equipment, she came to me asking that I help her disassemble them so she can pack them. The camera should have been damaged or even broken altogether because I had found it at a depth of 115 metres, and it is only designed to sustain 75 metres; but, to my surprise, the camera was still working. We played it and his mother was there. I regret that his mother will have this forever... If I had known the footage existed I’d have flooded it. I think the thing that really upset and saddened me about it was that his mom has it now – she has the footage of her own son drowning."

https://en.wikipedia.org/wiki/Blue_Hole_(Red_Sea)


Summary: The Blue hole is a natural sinkhole off the coast of Egypt. It is very accessible, there are many beginners, and there are many unscrupulous dive guides which lead to diver depths.

Some basic diving rules which when broken lead to deaths:

- Not diving with a partner

- Diving below the depth you should be

- Diving after partying the night before

- Rising back up too quickly


I think one big part of it is that tunnnel that leads out of the hole to the open ocean. Tunnels and arches to dive through magically attract divers, also for taking picures. The tunnel's ceiling is at 52-56 meters, which is exactly the depth that compressed air divers think they can risk diving to. The bottom of the tunnel however is at around 100 m, and nitrogen narcosis sometimes causes inexperienced divers to reach it...


> nitrogen narcosis sometimes causes inexperienced divers to reach it

For those of us who (don't) remember the 60's, experience can take many forms. I remember reaching a depth of 100' in scuba training, and being asked to do arithmetic at a whiteboard.

"Um, ask me how I wrote my thesis..."


Yeah exactly - any diving is dangerous if a diver behaves in the ways described in this article, it's not the site that's the problem per se. Just the depth that makes it easy for things to get worse when they go wrong I guess.


We have something like that, off the coast of Long Island. It’s the wreck of the San Diego; a WWI battleship that sank at the close of the war.

It’s upside-down, with a hole in the hull, and rests in about 40 meters of water (120 feet or so).

What makes it dangerous, is that it’s filled with silt, and it only takes an errant kick of the flipper to fill a room with zero-visibility mud.

People panic, and panic at 120 feet means the oxygen goes fast.

They nickname it “The wreck that eats divers.”

https://www.history.navy.mil/research/underwater-archaeology...


Entering a wreck at 40m without a guide line is asking to die.

I have over 10k dives and the closest I came to death was when I was guiding on the liberty wreck in bali when a small earthquake shook the wreck, I was barely 3 meter into the wreck that I had dived hundreds of times and couldn't find my way out. Fortunately my buddy was outside the wreck at the time and used his banger to guide me out.

Point is, shit happens, so you better plan for it.


> 10k

Gulp... That puts it in perspective. It's exceptional to dive a hundred times on a wreck in Bali and write about it on HN - and do both in the same live. Respect!


Thanks :)

You do about 1k dives per year if you are working in diving.

I have loads of respect for some of the recreational divers I have met with hundreds of dives, that is a lot of money and time to invest in a hobby.


Mad respect. I don't dive, anymore, but I think I only had about 30 or so in my log book.

What compounds it, is that we have an environment of "Macho Knuckleheads" around here. They will do things like dive the SD alone, and skip the decomp.


Have they installed ropes in the wreck or anything like that?


I don't know. The last time I dove it, was over 20 years ago, and they didn't have them, then.


Narcosis is nothing to trifle with. After a particularly bad experience at 150ft on air, I understand why some agencies advocate for a maximum equivalent narcotic depth* of 100ft.

*For the non-divers out there, it’s possible substitute a less narcotic gas - typically helium but not always - for a portion of the narcotic gas in a mixture. Equivalent narcotic depth (END) is a way to equate a mixture’s narcotic effect to that of air at a given depth.


Military and commercial divers have done some experiments with hydrogen to reduce narcosis without using helium. But the fire risk makes it way too dangerous for civilian sport diving.

Neon might also reduce narcosis but it's more expensive and the work of breathing is higher.


** 150 ft ~= 45 m; 100 ft ~= 30 m (for the other non-Imperials out here ;) )


Once you start getting to technical depths you operate under the assumption that you are alone, even when diving with a buddy.

I know some french federation divers who will tape their hands to their hand power inflator to avoid confusion when experience narcosis at depth.

At first I thought it was a goofy idea, but after experiencing debilitating narcosis at 60m I had second thoughts about it.


No you really don't. I do a lot of technical diving and depend on my buddies for safety. The key is to select reliable buddies who have been properly trained.

And taping your hand to your power inflator is just too stupid for words. Put some helium in the mix.


https://www.youtube.com/watch?v=hYuMN206Jzo

Interview with Tarek Omar (the diver rescuer in the article) and location shot. Much better than reading the article.


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


You might also like this one about a dive in Norway: The cave divers who went back for their friends[0]

[0] https://www.bbc.com/news/magazine-36097300


Thanks for sharing, it's a long read but very well written and worth the time.


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


Thanks for the link, but I much prefer the article to those American style documentaries, with the scary sound effects and endless repetition to build "suspense". Interview is at the 8:50 mark for those curious.


The article was fantastic. It brought everything to life in a way video essays can't.

Video crushes your imagination. It's factual, and leaves little mystery. Well-written narratives are full sensory waking dreams that you populate with sights and sounds, something you can inhabit.


How did you read it? It asked me for a subscription or an account or something. Instaclose.

Subject seemed interesting enough that I came to the comments to get alternative links, which have been provided, thank you posters.


It just asked to choose between adsupported and subscription model. You can switch off js if you dont want to see it.


I don't try to bypass walls. If they don't want my eyeballs I won't bother them.

Ofc, I suppose Germans who actually read it for the local info could be a lot more interested than me.


Also this -- professional diver discussing the video recorded by someone who dove there unprepared and died https://www.youtube.com/watch?v=Yv4aK2O1X_M


Go to 30:00 and just look at it. It's literally luring people in.


Thanks, very helpful.


The interview section is quite short; much shorter than that in the article. The documentary is fascinating regardless however.


Wow, just watching it gives me anxiety. Makes perfect sense what is happening and why divers can easily die there.

Thanks for the link.


I've dived the Blue Hole, recreational depths. I felt an evil presence there and had nightmares about the Hole 2 nights after, with some kind of blue energy trying to consume me.

I am not a superstitious person, and have dived multiple deep technical dives with bad visibility, below 0 Celsius sea water (poor dive computer) on sites with munitions, chemical contamination and war graves with body remains. This is the only time I felt that there was a large predatory presence watching me and all around me. Was offered to do the Arch, have the needed experience and clearances. Did not do, will not do ever.

The memorials and history of the place did not affect me in any way, I've worked rescue, dealt with dead bodies and attended many a funeral. I've participated in autopsies as part of my training. The blue hole was a strange enough experience that it stands out of all of my many dives.


Dread is quite the feeling. Almost quite impossible to describe.


I did my first dives in Dahab, Egypt including at the Blue Hole. This location was my first experience with narcosis; but, it was planned. Myself, my father, and our instructor dove down to 45m and he handed me a whiteboard to write on. He asked me very basic questions like how to spell your name and I remember really having to think hard to answer.

In general, if you are diving to see fish, it's rare to go past 20-30m (the minimum depth to exp. narcosis). The visibility is worse the deeper you go and typically if there is a reef at 30m there is also one at 15m where your oxygen will last longer, less cold, etc...

I don't think diving needs to be dangerous to be enjoyed. It's about seeing an entirely new world and the moving in the medium of water. The people who've perished at the Blue Hole are taking an extraordinary amount of risk - diving solo, descending to 150m - for 'achievement' purposes and I understand Omar's frustration.


This site is notorious in the professional diving community.

There is nothing particularly dangerous about it except the huge numbers of greedy dive centers who take inexperienced divers there.

To all novice divers reading this, dive within your limits and you have nothing to worry about. Do not listen to dive guides/instructors who encourage you to dive deeper than you are certified or in wrecks / caves without the proper training.

Diving is a calculated risk like most extreme "sports", and when you ignore those risks you endanger yourself and anyone else diving with you.

Don't expect your guide to care more about your life than you do.


In truth, diving done right is procedures, procedures, procedures. That's why many novices and professionals suck at it. It needs boring personalities, or these that can handle boredom. I don't have to remember about the danger, I don't even have to respect the danger: if I actually go through all the steps and all the procedures, the risk is minimal.

"If there was zero adrenaline, it was a dive done properly."

I've once taken an intro flight on a light aircraft. After I observed my instructor doing all his pre-flight procedures, I reflected "umm, you know, it's actually much less than I do for a simple dive." He thought for a moment, but found an interesting reply: "I'm not an expert, but I think, if we take a number of dives or flights, we have more diving-related deaths than light-aircraft-related." (He was talking about Poland though - i.e. cold water dives.)


As long as you're not flying an experimental aircraft, general aviation is naturally safer than diving. Since GA planes are aerodynamically stable and can glide, pilots (usually) have a lot more time to calm down and think through their options before the situation becomes really dangerous. Most emergencies can be resolved by identifying a flat field or calling an emergency at the nearest airport (which the FAA is encouraging pilots to do more often). Not to mention, getting a pilots license is about 10 hours of "how to fly a plane" and 30+ hours of "how to deal with emergencies" including the instructor cutting off engine power mid flight. There's a procedure for just about every situation and the most important ones are practically muscle memory by the time one receives a pilots license.


Here's a good look of the famous arch crossed by a freediver: https://www.youtube.com/watch?v=hrXQbucZUDA

A real shame that this diving site is known for all of these avoidable deaths.



Here's some good diagrams that show the shape of the hole: https://web.archive.org/web/20080321024116/http://www.blueho...


Those diagrams are very helpful, thanks. This drawing also helped me understand it:

http://maltatechnicaldiving.blogspot.com/2009/07/dive-site-o...


The article was very well-written but it would have been significantly improved by diagrams like that.


Sigh...the wikipedia article has a picture of various memorials family members of deceased divers built at the Blue Hole. The most prominent one reads "Don't let fear stand in the way of your dreams"...isn't that exactly the wrong message? The guy whose quote that is died when he was 23 years old.

https://upload.wikimedia.org/wikipedia/commons/0/03/Blue_hol...


A dive instructor I meet in Thailand in told me about this location. According to him it was common to be too narced (nitrogen narcosis) to make rational decisions when going under the arch at 52m, leading to fatal mistakes (like going even deeper).


I have been to that site twice , first time about 20 years ago as part of the diving course. I remember one of the exercises was to go to higher depth and do math exercises to prove that our thinking was not impaired due to the depth.

For sure that site was not branded as deadliest in the world, but already back then dive masters told us about people who lost their lives there.


The website has an interesting line of code:

> return console.log("Messaging without detection successfully executed.")


For predictable irony points that's coming from a component provided by SourcePoint who claim to be a "privacy compliance platform for digital marketing, with the tools to protect consumer privacy, manage compliance, and optimize revenue."


That was a sad read. Essentially the hole in the earth version of mount Everest.



What a great story teller! I can’t put my finger on it, but the cadence and length was just spot on.


Perhaps worth adding (2012) to the title. It is evergreen, still relevant, but worth noting that it is almost 10 years old.


Idle speculation, perhaps a diver could answer - could it be that the reef forms a kind of natural solar pond, leading to an unusual osmotic (and therefore density) gradient? Thus resulting in divers suddenly dropping like a stone when they hit a certain depth? The Red Sea is one of the saltiest bodies of water in the world.


All your buoyancy comes from non rigid devices (vest, suit). As you go deeper those devices compress and you lose buoyancy causing a feedback loop. Compounded with loss of vertical references, you can quickly sink to the depth where the air you breathe will become toxic. At that point you don’t have the mental capacity to save yourself.


More likely that the target depth is down near 50m, which is well into the narcosis range for surface gas mixes. Particularly for inexperienced divers it is very easy to not realize what is happening and become too stupid to save yourself.

Higher salinity may exacerbate that but not by too much.


> 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.


As a diver descends, they have to add air to their BCD (Buoyancy Control Device) to maintain neutral buoyancy (and release air when they ascend).

Without that compensation step, as a diver descends their buoyancy becomes increasingly negative.

Add a level of narcosis for descending below 40m, mix in some excitement/stress, and some equipment configuration issues (e.g. too much weight), and the task-loading can cause some people to forget/skip routine techniques such as adding air to maintain neutral buoyancy.


I like skydiving and scuba diving. And in both cases I always prepare like a madman. The activity itself comes with plenty of risks, and I'm just there to enjoy it by reducing the risks best I can.

That means the blue hole can go screw itself. I'll stick to a maximum depth of 25 meters or so and my goal is to see shipwrecks (from a distance) and pretty fishies.

As for skydiving, I want a good view, no wind, a maximum of one tiny cloud, and a dropzone with good packers and craft beer.

There are plenty of people out there BASE jumping or deep-sea diving. There are plenty of them recording their own deaths. I plan to not be part of those people.


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.


It turns out almost all the organizations follow the same training standards set out by the WRSTC (World Recreational Scuba Training Council). The big exception is CMAS which past level 2 no longer is comparable to the WRSTC program tracks since it allows for decompression diving on air down to 40m (level 2) and 56m (level 3).

This means even with an advanced or master diver certificate from PADI, (NAUI, SDI, SSI, etc...) the tables you learn to use do not go beyond decompression limits (requiring mandated decompression stops on your ascent) since they stop at 30m. It used to be 40m but I believe the standard has become more conservative since I was last teaching. NAUI does have supplemental training that goes beyond WRSTC standards but a lot of that has to do with the science and ecology of the underwater world more generally.

All open water level certs (usually the most basic level cert) expects students to be fully autonomous (with their buddies) by the end of the course. If you sign up for an open water dive in southern. California for example, it is rarely a guided experience and most people form groups of 2-3 on the boat and go and enjoy the water, coming back within an 1-1.5 hours. Almost everywhere else I have worked, it is expected (by the guests...) that all dives in open water are lead by a certified dive master and not self lead in small groups. I personally think this is a result of the way the standards and incentives work for dive operators to encourage that dependency on their outfit and keep the money flowing in.

Generally recreational diving is very safe but even working as an instructor for a few years at a few different outfits, there is always a handful of fatalities. I really like the comparison to Skydiving someone else made, except its a much more subtle danger since you dont actually need to be in top physical shape to do this activity (even though it is required by the certification agencies).

The only other thing I find interesting is all the certification agencies are for the INSTRUCTORS (hence the I in PADI, NAUI, SSI...). These orgs are outfits that enable recreational scuba operators to have a standardized set of empirically derived safety limits to protect the instructor and shop liability (not the student's). More often than not, especially in far flung, remote diving destinations, caution is thrown to the wind and people do not always follow the prescribed standards.

Source: OWSI (Open water scuba instructor) with multiple agencies as well as CMAS level 3 diver


Lots of things are dangerous. Motorcyclists I know each have a row of busted helmets in a closet. Ski long enough and you'll break something. Bicyclists die on the road every day (in America) and few give it a second thought.

I wonder how diving compares to other off-track sporting activities. Does it have a worse record?


I don't know stats, but checking out the passings section of scuba board does indicate it's a fair number of people. The thing that is different about diving from bicycling or skiing is you really don't need to be physically fit to dive. It's relaxing and easy, people dive into their 70s and 80s so there are a lot of heart attacks of older people that get chocked up to diving and may just be natural causes.


What a noble soul.. "He brings up the bodies because he wants to help, says Omar. "It isn't about money for me. I don't ask for anything. I just charge the cost of the gas."


This documentary investigates specifically why the people are dying there. Very well made.

https://youtu.be/hYuMN206Jzo


I found this terrifying, but incredibly captivating!


Site blocks Brave.


(2012)

argh


Can’t read without clicking the “I agree to tracking” full page pop up.


Crazy!


I remember several years ago I watched the video on YouTube where Yuri sank to the bottom of the Blue Hole and drowned in a drunken narcotic state. Pretty much confirmed I never want to bother with scuba diving. ROVs seem cooler anyway and can go way deeper.


This type of dive is extremely atypical in terms of risk, and also reward. It appeals to a certain kind of person interested in technical diving and/or bragging rights. As far as seeing pretty fish or coral, there is no point in going this deep since it's dark. 99% of divers are staying above 30m, where things are a lot safer and more interesting.


Indeed; nitrogen narcosis is almost non-existent within the 18m standard open water limit, and even down to 30m is unusual. Just find a reputable dive company taking you around a reef and it's really very safe.




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