I spent a long time looking at those empty plastic bottles, wondering if they could save me.
September 5, 2012 10:22 AM   Subscribe

If I was in a life threatening crisis, how much time would the oxygen in a soda bottle buy me.

Not that I was driving through the holland tunnel recently or anything, wondering about what I would do if it cracked and filled with a tidal wave of water, but if it did and I had two small sealable soda bottles with me, would the oxygen in them be enough to buy me time to swim out of the middle? How much time would it get me? What does that time translate to in swimming length? I understand that, hypothetically, the force of impact would probably kill me, but if I survived, would I be able to make it out?
posted by history is a weapon to Health & Fitness (13 answers total) 3 users marked this as a favorite
The average adult male lung capacity is 6 liters, according to wikipedia. Your soda bottles would be a small fraction of that and would be of almost no use to you.
posted by procrastination at 10:24 AM on September 5, 2012

The average volume of a human lung is 6 liters, but "tidal volume" is about 1.5 liters. Anyway, assuming you needed to take a deep breath in order to survive, two small bottles of air would not do the trick.
posted by KokuRyu at 10:25 AM on September 5, 2012

What the above 2 answers indicate is the right "book" answer, but the wrong answer to your question.

With shallow breathing, you will have several minutes of extended breathing. The difference is the way the human body cycles the oxygen, thereby giving you a longer usage than the actual volume.

In life and death situations, this can make all the difference. 1st hand experience if people surviving with this amount, or even less (avalanches, car under water).
posted by Kruger5 at 10:46 AM on September 5, 2012 [1 favorite]

Of course, if you could store the oxygen at greater than atmospheric pressure, it would last longer (see this recent askMe about the maximum pressure a plastic bottle can sustain).

The Spare Air Model 300 stores stores what is 85L of air when reduced to atmospheric pressure, in a metal cylinder 13.4" / 34 cm long and 2.25" / 5.71 cm in diameter, providing 57 surface breaths of 1.6L each. It's intended as a emergency device for use by divers, but similar products are sold to allow escape from a flooded helicopter (as a "Helicopter Emergency Egress Device").
posted by James Scott-Brown at 11:14 AM on September 5, 2012

Though the former suggestion would require attaching some kind of regulator to the plastic bottle to reduce the pressure, which is probably impracticable . . .
posted by James Scott-Brown at 11:16 AM on September 5, 2012 [1 favorite]

What the above 2 answers indicate is the right "book" answer, but the wrong answer to your question.

Well, it may be the book answer, but I suspect it is the right one. The OP is talking about swimming out of a flooded tunnel. It is going to be dark; the water is likely to be cold and full of oils and gasoline and whatever crap was on the road; there will be other people thrashing around and cars floating up towards the top of the tunnel for a while until all the air escapes from the compartments and they manage to sink, meaning that the ends of the tunnel near the air will be packed with whatever cars were in there. In short, it is going to be insane chaos, probably hard to even get out of the car and certainly hard to swim any distance, and not a place where you can practice tidal breathing into a bottle and hope for someone to come along.

Even if you could hang out calmly wait, it is going to be extremely difficult to even use the air in the bottles. When they are opened, they will have to be held upside down to keep the air from escaping. Water pressure will force the air to the top of the bottle, so in order to reach what is in there you will have to carefully squeeze the bottle to bring the air level down to the mouth of the bottle, then suck it into your lungs without getting water in that will make you sputter and cough.

I'd suggest to anyone that they try it in a swimming pool under calm conditions and see what it gets you. I played around with this as a kid, and it got me nothing (though I was using a small bucket and trying to tip the air up into my mouth). You would probably do better to try and swim from car to car and use the air pockets within to breath.
posted by procrastination at 11:47 AM on September 5, 2012 [1 favorite]

I assume you are asking about empty soda bottles that you happened to have on hand and not soda bottles that were filled with 100% oxygen. Rough, quick calculation is that you would get 72 ml of oxygen out of them or 360 ml of air. Their buoyancy might slow your swimming underwater.

So let's say you take a deep inhalation before the water comes. The vital capacity of the average adult male lung is about 4.6 liters. How far can you swim on that underwater? Add on about 8% for your additional soda pop air assuming you squeeze all of the air out of the bottle.
posted by dances_with_sneetches at 11:53 AM on September 5, 2012

Unless you're in the habit of driving with a weight belt on (and maybe not even then,) you're going to lose much more time fighting those bottles as you try to swim with them than you'll gain from their contents.
posted by contraption at 12:08 PM on September 5, 2012 [1 favorite]

if it did and I had two small sealable soda bottles with me, would the oxygen in them be enough to buy me time to swim out of the middle?

No. That'd be enough for maybe half a lungful, total. Which if you're really good will keep you going for about 60 seconds. The tunnel is well over 8,000 feet long, so if you were in the middle, you'd have about 4,000 feet to swim. That's the better part of a mile. Michael Phelps could swim about 100m in about a minute, so it'd take him at least twelve minutes to swim from the middle of the tunnel to the surface, under ideal conditions and not slowing down at all. Of course, that involves breathing every few seconds the entire time, as you'd be consuming a ferocious amount of oxygen.

Forget it. You'd need scuba gear.
posted by valkyryn at 12:22 PM on September 5, 2012

Your best bet would be to try to get on top of the water and stay there and kinda body board out on the pressure.
posted by Matt Oneiros at 1:09 PM on September 5, 2012

You are probably better off hyperventilating (if you still have air in the passenger compartment of your car) to build up the oxygen supply in your bloodstream and using the bottles to first help you figure out which way is up and second help pull your body to the surface.

Odds are you will be extremely disoriented and will need some guidance once you are in the water. Knowing which way is up will be extremely important, assuming that you can go up to get out - if you are in a tunnel that collapses and have to swim a good distance laterally you can still get to the roof of the tunnel use that to guide you.

Another thing to remember if you are surfacing from an extreme depth is to blow out as you ascend. The air in your lungs will expand and could rupture your lungs if you don't exhale a bit as you go.
posted by natteringnabob at 2:17 PM on September 5, 2012

would the oxygen in them be enough to buy me time to swim out of the middle?

The Holland Tunnel is 8,558 feet long. So, the midpoint is 4,279 feet, or a little over three-quarters of a mile, or 1304.24 meters.

The longest Olympic swimming event is the 1500 meter freestyle. That's 30 lengths of the pool. The current world record is 14:31.02, set at this summer's games by Sun Yang, who had the luxury of swimming on top of the water, not underwater, where he would be certainly slower.

The average human -- at rest -- takes in 12-20 breaths per minute. You will certainly be working hard doing this swimming, but even at 20 breaths per minute, that's 290 breaths in 14.5 minutes if you somehow magically manage to swim a world record time, underwater, to escape the Holland Tunnel.

You would need a scuba tank, and while bottom time is highly variable from person to person, I don't like your odds.
posted by Cool Papa Bell at 3:58 PM on September 5, 2012 [1 favorite]

Just as a point of reference, you may be interested in the Personal Rescue Enclosure^ -- known colloquially as the "beach ball" or "rescue ball" -- that was considered in the early days of the Space Shuttle program as a means of transferring astronauts -- who did not travel with pressure suits -- from a disabled shuttle to a rescue shuttle.

These were considered the "most minimal spacecraft possible", and came with an oxygen supply of about an hour.

You may also find interesting the account of the death of Dave Shaw, one of the world's most accomplished cave divers.
posted by dhartung at 4:11 PM on September 5, 2012 [2 favorites]

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