Movie Theater Diving Into the Unknown
- Thread starter Jigstick
- Start date
I have not seen the movie and as a cave diver I am hesitant. The challenge with a movie about tech/cave diving is that in order to make it attractive to the general audience, you have to dumb it down to the point of being wrong and annoying to the geeks. Conversely, if you do the subject justice, you are going to loose 99% of the paying audience.
What we do not realize in normal life is how well our species is adapted to normal - i.e. near sea level - conditions on this planet. Once we go up in the atmosphere or down in the water column, the environment becomes progressively lethal to our biology without obvious warnings.
When flying above 12,000 feet for example, breathing additional Oxygen is a life saver. However, 100% Oxygen is going to kill us if breathed below 20ish feet of water column. You heard of antioxidants. Oxygen does not just corrode our car's metal it also oxidizes molecules that are important for our body, especially for the nervous system. So we have antioxidative mechanism built into our cells that work great at sea level but get overwhelmed when the product of pressure and concentration (partial pressure) of Oxygen gets too high. The result is similar to epileptic seizures (called crazy chicken dance), which is obviously not good when you are surrounded by water and need to suck your life-sustaining gas through a mouthpiece.
Regular air (21% Oxygen) will be toxic in the same way beyond 200ish feet of water. But before that happens, the 79% Nitrogen have already whacked you silly like a bottle of booze. See, Nitrogen is 'inert' at sea level but messes with your neuro-transmitters under higher partial pressure.
So, we decide to ignore nature telling us that we do not belong there and replace the Nitrogen with Helium and take some of the Oxygen out of the mix. Cool, we solved the problems of Oxygen toxicity and Nitrogen narcosis but now this gas is hypoxic at lesser depths and we need to switch gases on your way down and up or we will croak. We could dive a rebreather that mixes the breathing gas on the fly and scrubs the exhaled carbon dioxide like an anesthesia machine but when (not if) this thing fails, we are back on our premixed backup bottles. Fuck this up and you are done.
Meanwhile, any gases that are not metabolized like Nitrogen and Helium will dissolve in our blood under pressure and need to come out of solution slowly during a calculated and timed ascent. Otherwise, the bubbles forming in our bloodstream will put us in a grave, wheelchair, or diaper. Then, add the potential of getting lost or trapped in a cave or wreck and you begin to understand why life insurances frown upon these hobbies or professions.
So why are people doing this stuff? Because it gains you access to environments that are of mind-blowing beauty and mystery. Cave diving is a valid Space EVA substitute for us poors - possibly even more interesting in the long run due to the much more diverse environment. I would not be surprised if a ride in Bezos' rocket penis would be seriously lame in comparison.
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Too much trooth, let us beleeve we can dive deep with a oxygen tank and a vortex scope so we sink.
You got ALL THAT from a Simpson's episode?
Damn.....
(ok, I'll admit I'm an ass, but that was funny)
Seriously, that really was one-hell of a write-up, man. I have only dreamed of scuba-diving (as well as parachuting) for a lot of years, but due to certain infirmaties it is highly suggested I avoid such activities....
In other words, while I don't know from Shine-O-La, that sounds REAL, man. Very-lots-of-much!
typical first symptom of O2 toxicity at depth is seizures which obviously isn’t good and highly lethal. The accident didn’t involve that. Seemed more mechanical with their rebreather blenders. Actual footage from the dive is used in the film. It truly is an amazing movie. Very well done.
