questions about SCUBA

[cfern]

Questions regarding a film that will be made Summer 2004

Is it possible for a scuba diver to pass out underwater from the inhalation of the (oxygen?) from the scuba tank?

Can a scuba diver pass out underwater (basically fall into deep sleep) and stay alive from the oxygen from the suba tank?...waking up some twenty to thirty minutes later...?

A character in the film is supposed to hide out underwater, wearing a suba suit w/tank to keep him breathing for twenty to thirty minutes. While he is hiding, he passes out from being overwhelmed w/fear.

Thanks!

 

[Bob3]

Just be sure to have the guy wearing a full face mask, that's about the only way to take a nap without ingesting large amounts of water.
It also wouledn't hurt to take a scuba course, the added familiarity with terminology would make the yarn much more respectable.
"... passes out from being overwhelmed w/fear" dunno about that one, how about just falling asleep from exhaustion?
I used to doze from time to time while diving with a helmet.

 

[AzAtty]

Question 1: Yes. Pure oxygen is toxic at depth, which leads to seizures and loss of consciousness. Now, if you're talking about AIR as the breathing gas (not pure oxygen), then usually loss of consciousness is the result of a substantial contaminant level in the breathing gas supply, such as carbon monoxide. If the breathing gas is contaminated with carbon monoxide, for instance, then it's kind of like breathing from a hose connected to your car's exhaust pipe.

The air we breathe here at the surface can also become toxic at depth, but that wouldn't happen until you go beyond recreational limits.

Question 2: If the diver is breathing the appropriate gas for his/her depth and just "passes out" for a reason unrelated to gas supply (say, s/he gets hit on the head by someone's weight belt) or some physiological problem; and assuming that the person has an adequate gas supply, and assuming the regulator stays in the person's mouth, and assuming s/he doesn't get eaten by a shark, then yes, it's possible that the person will regain consciousness. However, depending upon how deep and how long the person was underwater, the person may have a decompression obligation (meaning they'll likely get the "bends" if they ascend without following decompression protocols).

It sounds like the scene will be some desperate individual is trying to escape from somebody, stumbles across a fully assembled and equipped scuba rig, and hops in the water to escape. Overcome by fear (maybe this is where you need a shark...sharks are good for scuba movies), the person faints.

There are other practical issues to deal with when dealing with underwater work, but if your question is whether the event could possibly happen, yes, it could. I'm certain there are others here who have seen people pass out underwater. Bob3's idea about the full face mask is probably the best way to get past the problem of a regulator falling out of an unconscious diver's mouth.

 

[-=>Larry<=-]

cfern once bubbled...

Is it possible for a scuba diver to pass out underwater from the inhalation of the (oxygen?) from the scuba tank?

Best you should read the Medical sections, and track for a while - BUT - you generally breath pressurized air, and aside from CO, CO2 poisoning - theres no "reason" to pass out.
There is a version where Air is mixed with O2 - breathing that at too deep a depth can lead to seizures.

Can a scuba diver pass out underwater (basically fall into deep sleep) and stay alive from the oxygen from the suba tank?...waking up some twenty to thirty minutes later...?

Stay alive for 30 minutes - no problem - do it all the time. Pass out, fall into deep sleep - that's really not normal - although one could feasibly go to sleep [a full facemask would remove the danger of spitting the regulators out in your sleep]

A character in the film is supposed to hide out underwater, wearing a suba suit w/tank to keep him breathing for twenty to thirty minutes. While he is hiding, he passes out from being overwhelmed w/fear.

Thanks!

Does one pass out from being overwhelmed with fear in normal life?? - Otherwise, the first sentence is feasible.

 

[Diver0001]

cfern once bubbled...
Questions regarding a film that will be made Summer 2004

Is it possible for a scuba diver to pass out underwater from the inhalation of the (oxygen?) from the scuba tank?

Can a scuba diver pass out underwater (basically fall into deep sleep) and stay alive from the oxygen from the suba tank?...waking up some twenty to thirty minutes later...?

A character in the film is supposed to hide out underwater, wearing a suba suit w/tank to keep him breathing for twenty to thirty minutes. While he is hiding, he passes out from being overwhelmed w/fear.

Thanks!

If you think people will believe the overwhelmed by fear thing then you're already deep in "B" territory anyway so what does it matter if your scuba facts are straight? In fact it might work out better if they aren't.

R..

 

[cyklon_300]

Based on what you've outlined for us, the plotline sounds pretty laughable.

Maybe you could hire one of us to be your technical advisor...hint, hint.

If you blow up any compressed air cylinders, don't make the same goofy mistake seen in Jaws...you know, flames and black smoke and all...

 

[cfern]

thanks a lot for answering my questions, I really appreciate it.

just to clear up some confusion...
this is a student film production.
this is the situation in the first scene:

a young man is taking a night time scuba class in an indoor pool facility. after he puts on his scuba suit and gear, he notices some classmates in the distance falling to the floor choking. then someone far away yells about the air being contaminated. the man and his classmates all start to panic. the only way out of the facility is in the direction of the three people that are unconscious (where the air is "contaminated")...so basically there is no way out. more classmates, this time closer to the man, start feeling faint, and collapse to the floor. in a confused panic, he jumps into the pool besides him, and remains underwater. he's so shocked by what he's seen that he passes out while underwater. twenty minutes later he awakens and rises to the surface, not remembering yet, what had happened earlier.

and just for the record, I'm obviously not the script writer (by the looks of my writing)...I'm just doing research for the film.

is this situation at all believable? are there scuba class sessions that are held at pool facilities? any feedback? we need scuba expert advice...

thanks again!

 

[Diver0001]

cfern once bubbled...
thanks a lot for answering my questions, I really appreciate it.

<snip>

and just for the record, I'm obviously not the script writer (by the looks of my writing)...I'm just doing research for the film.

Good for you. Take distance while you still can....

is this situation at all believable? are there scuba class sessions that are held at pool facilities? any feedback? we need scuba expert advice...

thanks again!

More believable is that he stays underwater as long as he can and then surfaces because his tank is empty.......

Alternatively he could take the tank under his arm and breathe on it on his way to the emergency exit. He runs out of the building and ..... uhh ..... gets abducted by water breathing aliens and then passes out from the shock ..... I suppose this is why I don't write scripts.

R..

 

[cfern]

Diver0001 once bubbled...

Good for you. Take distance while you still can....


More believable is that he stays underwater as long as he can and then surfaces because his tank is empty.......

Very true. BUT...this would make the opening "dream sequence" confusing and out of place.

Alternatively he could take the tank under his arm and breathe on it on his way to the emergency exit. He runs out of the building and ..... uhh ..... gets abducted by water breathing aliens and then passes out from the shock ..... I suppose this is why I don't write scripts.

R..

This is where "in a confused panic, he jumps into the pool..." comes into place.

Diver0001 - thanks, I'm saving your suggestions.

 

[AzAtty]

Reality check: if the air in a building is "contaminated", and I have a perfectly good diving rig set up beside me, why would I jump in the pool? I'd simply sling the rig onto my shoulder, pop the regulator in my mouth, and walk out the door breathing my nice clean gas from the cylinder.

I suppose if the student saw peoples' skin melting, or a shark in the door or something he might jump into the pool instead of walking through the door.

I suppose it could happen the way you suggest, but I don't think it will score many points for being realistic.