Trapped in a Sunken Tug Boat

[Ben]

Holy crap, this would have been an ordeal. Crew cook trapped for three days in a sunken boat 100' underwater. I'm surprised the air stayed breathable that long. It must have been a pretty big air pocket.


http://www.foxnews.com/world/2013/06/12/nigerian-cook-trapped-for-3-days-in-sunken-ship-tells-incredible-story-survival/?test=latestnews

[geronimotwo]

holy cow, that's amazing! 

[Sergeant Bob]

That really is truly incredible! He's a very lucky man.

[Pharmacology]

That's freakin nuts.

I would've lost my *expletive deleted*it after about 5 hours.

[zahc]

I often wondered, if you had a large bubble underwater, with some way to prevent it from floating upward due to buoyancy, what would be the steady-state composition of the atmosphere in that bubble?

Obviously humidity would be 100%. There is some dissolved oxygen in water--that's how fish live. Eventually, the vapor pressure of oxygen and CO2 in the bubble would come to equilibrium with the dissolved oxygen and CO2 in the water. For a large enough bubble, the presence of a human in the bubble wouldn't perturb the atmosphere as the whole water/air surface is exchange surface. Under what depth/temperature conditions could a human live in a "large" bubble? Are there any?

[never_retreat]

As a scuba diver. What that article was missing is how did they get the guy to the surface? A 5 day dive to 100'? the guy would be bent like a pretzel when they brought him up.

[Ben]

As a scuba diver. What that article was missing is how did they get the guy to the surface? A 5 day dive to 100'? the guy would be bent like a pretzel when they brought him up.

In a non-third world country, he would have just been stuck right into a chamber for a few days as soon as he hit the surface. Don't know what happened here, though apparently the tug was somehow related to Chevron from follow up articles I read, so they may have had on the ball medics and equipment available to take care of him.

[makattak]

As a scuba diver. What that article was missing is how did they get the guy to the surface? A 5 day dive to 100'? the guy would be bent like a pretzel when they brought him up.

I followed the link to a more detailed story to find:

A safety rope and oxygen mask were later deployed. But before he could be brought out, his body pressure had to be kept at a safe level. So, a vial of warm water was also sent down for a quick bath after which he and the diver got into the decompression chamber (DCC) for the journey back to ‘life’.

[CNYCacher]

As a scuba diver. What that article was missing is how did they get the guy to the surface? A 5 day dive to 100'? the guy would be bent like a pretzel when they brought him up.

As a non-scuba-diver who has a layman's understanding of the concepts involved, I think my reaction would be to blow as much oxygen into the space as possible, fetch or send for a few gallons of fresh water, and then figure out how to get him out of there.

Assuming you could hook him up with another SCUBA, how long would the decompression ascent take?  Or would he just need to go to the surface and right into a pressure chamber?

[Ben]

It sounds from Mak's article like they brought a portable chamber down and swam him into it. Otherwise it would be getting him up and into a chamber right away. Three days at 3 atmospheres, he'd be hanging off till his next birthday doing deco stops. :)

[makattak]

Now I'm no diver and am also a few years out of chemistry (by a few, I mean almost half my life)...

But wouldn't the pressure at that depth also help explain how he survived for so long? The "air pocket" would have been under immense pressure, meaning there was a lot more air (and therefore, oxygen) in it than the same volume at sea level.

[CNYCacher]

Now I'm no diver and am also a few years out of chemistry (by a few, I mean almost half my life)...

But wouldn't the pressure at that depth also help explain how he survived for so long? The "air pocket" would have been under immense pressure, meaning there was a lot more air (and therefore, oxygen) in it than the same volume at sea level.

100 feet is roughly 4 atmospheres, so the air would be 1/4 the volume it normally would be.

That's why freedivers, even with a huge lungful of air, can coast down after reaching a certain depth, the pressure crushes their lungs until they are non-buoyant

[Pharmacology]

Now I'm no diver and am also a few years out of chemistry (by a few, I mean almost half my life)...

But wouldn't the pressure at that depth also help explain how he survived for so long? The "air pocket" would have been under immense pressure, meaning there was a lot more air (and therefore, oxygen) in it than the same volume at sea level.

Thanks man. I think I just popped a few fuses trying to remember how vapor pressure works.  LOL

[Ben]

100 feet is roughly 4 atmospheres, so the air would be 1/4 the volume it normally would be.

Actually three. ~130' is four.

[CNYCacher]

Actually three. ~130' is four.

How many atmospheres at the surface?

[Ben]

How many atmospheres at the surface?

One, which gets you down to 33'.

[CNYCacher]

One, which gets you down to 33'.

So if I took a balloon from surface to 33' depth, would the balloon be 1/1 volume of 1/2 volume when i got there?
At 66', would it be 1/2 or 1/3?
At 99', 1/3 or 1/4?

Am I mistaken in my terminology or my physics?

[Ben]

http://www.doalasvegas.com/html/scuba_formulas.html