Vacu-sealing People

[cmonidareya]

This question involves the safety/hazards associated with putting someone in a giant vacu-seal bag and then turning on the machine to suck out all the air. This supposes that the person being vacu-sealed would have a straw/air tube punctured through the plastic and then taped so that the only air from the outside would reach the person's lungs and not the inside of the bag. Does anyone here know of any possible hazards or dangers associated with this activity? Would the eardrums be affected or any possibilities of embolisms or would the person basically just get all sweaty and hot? And upon opening the bag again, would there be a possibility of the bends? Has anyone tried to vacu-seal a live person before? (I am assuming vacu-sealing a dead person would be a moot point).
Any help or information on this would be appreciated.

[Q.E.D.]

Since it's a very flexible thin plastic bag, the pressure exerted on the person's body wouldn't change. The partial vacuum in the bag would allow the air pressure outside to force the bag to conform to the person's shape and thus maintain a constant pressure. No bends, no embolisms, no ruptured eardrums.

[scr4]

Originally posted by cmonidareya
(I am assuming vacu-sealing a dead person would be a moot point).
And vacu-sealing a live person is not?

Anyway, I think the main danger is the force on your chest. Most likely you will suffocate because the plastic bag will make it impossible to expand your chest and inhale air. You might get away with it if you inhale and hold your breath during the sealing process, and exhale later to create some room (slack).

At least that's my opinion based on logic, not experimental evidence of any kind.

[Joey P]

I've seen it done to a live person. It was between two sheets of latex. I saw this on an HBO special called Real Sex.

[captainQwark]

In an issue of Bizarre magazine I saw a picture of a live woman vacuum sealed in a bag. It was photographed at some kind of alternative circus.

[Rusalka]

This sounds very creepy, I worry why you would want to do something like this? Sealing someone in a bag like this would definitely KILL them, even with an "air straw".

The reason is that we sweat for a very good reason - to cool us off. Sealing someone in a bag would be very dangerous even for a short period because they would overheat quickly. Look up "heat stroke" and other ramifications of overheating. I would not recommend doing such a thing for any reason. (and I'm still worried why you're asking this question)

[Philster]

Yes, what Rusalka has mentioned. It is more dangerous than it appears to have the skin sealed up like that. And searching on some sites that I'm not aloowed to post here reveals a number of warnings about it.

Search on cocooning latex rubber plastic. Some sites have warnings about wrapping the body because of health risks and death from overheating and not perspiring.

[Mangetout]

I saw an article about the guy who was sandwiched between two sheets of latex - IIRC he said that he started to experience some of the effects of sensory deprivation (it was so close fitting that he couldn't move at all).

[CookingWithGas]

Notwithstanding the posts that say this has actually been done, I am still wondering about the air pressure issue. If you have a straw to breath through, it seems that the low pressure on the outside of the eardrum due to air evacuation combined with the higher pressure on the inside of the eardrum due to air coming in from the straw into the eustachian tubes would cause at a minimum notable ear popping, similar to ascending quickly in an airplane. The vacuum would basically suck your eardrums outwards. The effect could go from uncomfortable to dangerous, depending on the pressure differential.

As a Food Sealer owner who has done vacuum sealing on a variety of (non-living) objects, scr4's concern
Anyway, I think the main danger is the force on your chest. Most likely you will suffocate because the plastic bag will make it impossible to expand your chest and inhale air. is nothing to worry about. The bag is perfectly flexible, it's not pressing on your chest, it's clinging to your chest. It's not pushing on the contents, it simply has the air sucked out of it. (The concern might be valid if you were talking about shrink-wrap, a whole different story.) As long as your have a straw to breath through you can breath fine.

And now I'm getting kind of creeped out.

[scr4]

Originally posted by CookingWithGas
...scr4's concern
is nothing to worry about. The bag is perfectly flexible, it's not pressing on your chest, it's clinging to your chest.
Yeah, I started wondering about that after I posted. Ther air is pumped out from the gap between the body and the bag, but I guess it doesn't exert any force on the body. Thanks for the correction.

[Mangetout]

... as long as there is enough stretch or pucker in the bag material to allow your chest to expand.

[Chowmein]

What would happen if you did vacu-seal a dead person? How would that affect the rate of decomposition. Also, would there be any possible way for the scent to escape the vacu-sealed bag? (Would a corpse-finding dog be able to locate the body if it were burried in the woods?) Since all the air is out of the body, would it float in water? (If I throw it in a river, will it stay at the bottom?)

Note: I don't have any dead bodies that I need to dispose of. . . yet.

[cmonidareya]

For those of you curious as to why I asked this question (and thanks for your input): My brother-in-law (who is 20 btw) has a girlfriend who has one of those machines to store pillows and comforters in a third of the space or whatever by vacu-sealing them. They asked me (for I am a font of knowledge to them) what would happen if a person was put in it (I believe they are planning a party and wanted to do this as a goofball stunt). I did not have an adequate answer, but I figured the SDMB would be a good place to find out what other people have to say about the dangers. If they actually go through with it, I will let you know what happens for the definitive answer.

[CookingWithGas]

Originally posted by Chowmein
What would happen if you did vacu-seal a dead person? How would that affect the rate of decomposition. It slows, but will not stop, the decomposition because of the lack of air. However, there is such a thing as anaerobic bacteria. Plus, you can't evacuate all the air, since there are some body cavities that will not completely collapse, and there is oxygen in all the tissues anyway.
Also, would there be any possible way for the scent to escape the vacu-sealed bag? (Would a corpse-finding dog be able to locate the body if it were burried in the woods?) Since all the air is out of the body, would it float in water? (If I throw it in a river, will it stay at the bottom?)

Note: I don't have any dead bodies that I need to dispose of. . . yet. [/B] This is an attribute of the bag material rather than the fact that it has been evacuated of air. I don't think the bag exists that would be absolutely impermeable to odors, especially to a trained dog.

[Padeye]

The latex vacuum bag bit is nothing close to a proper vacuum even as cool and fetishy as it looks. There is only enough pressure difference to get the membrane to cling to the body. A pressure difference of as little as 1psi would put a load of several hundred pounds on a person's abdomen making it impossible to breathe.

There is another way to try this experiment that several foolhardy people do; they try to breathe with a garden hose while at the bottom of a swimming pool and find it impossible to doe so due to water pressuer at even a shallow depth. FWIW water pressure increases by one atmosphere for appriximately ever 32 feet depth.

Vacuum bagging is common in woodworking and composite building because it's a cheap way to get incredibly high clamping pressures on large objects. Say you want to glue a veneer to a 24"x48" table top. Slip it into a plastic bag, pump all the air out and you have the same pressure as if you had pure more than 16 tons of sandbags on top. As Tennesee Ernie Ford says, "bless my soul."

[Incubus]

hey I did that 'trying to breathe underwater with a long tube trick' once!

I took the metal tube used to scrub the pool and used it as a very long snorkel. However I discovered much to my surpise that it was nearly impossible to breathe even a mere nine feet under water.

[aeropl]

I seriously doubt it would be dangerous if you made sure they had air and could communicate. The pressure of a bag deflated by a vaccum cleaner is not going to crush anybody. If you deflated the bag and let them out after they started to sweat you should be fine.

[Shalmanese]

Let us know how it goes

bookmarks Darwin Awards

[Mangetout]

Originally posted by Padeye
Vacuum bagging is common in woodworking and composite building because it's a cheap way to get incredibly high clamping pressures on large objects. Say you want to glue a veneer to a 24"x48" table top. Slip it into a plastic bag, pump all the air out and you have the same pressure as if you had pure more than 16 tons of sandbags on top. As Tennesee Ernie Ford says, "bless my soul." Are you sure that this effect isn't at least partly due to the porous nature of the wood - properly dried wood contains air between the fibres, this can be evacuated, causing a much greater pressure differential.

for example, I'm certain that you could vacuum-pack an inflated balloon and it would not shrink because you are not pumping out the air from inside it, however, if you were to take a sphere made of thin (but rigid) plastic and drill some holes in it, it would become possible to evacuate the gaseous contents of the sphere and vacuum-packing it would crush it.

[CookingWithGas]

Originally posted by Padeye
[B]A pressure difference of as little as 1psi would put a load of several hundred pounds on a person's abdomen making it impossible to breathe. I think you are overlooking the point in the OP that the person would have a channel to outside air into their lungs, causing the internal pressure of the person's body to be equal to the ambient air pressure. Although I'm not sure--I'm open to hearing further reasoning on this issue.[/quote]

There is another way to try this experiment that several foolhardy people do; they try to breathe with a garden hose while at the bottom of a swimming pool and find it impossible to doe so due to water pressuer at even a shallow depth I bbelieve the claim but not sure I understand why this is so. Is it bbecause the water pressure at that depth overwhelms the air ppressure in the hose, and your lungs can't push out against the water pressure sufficiently to draw in the air?

And lastly--for the purposes of the physics of it, is being in an evacuated bag with a straw in your mouth really the equivalent of being subjected to the pressure of, for example, being deep underwater? (I think not, note my earlier post, but I welcome corrections.)

[CookingWithGas]

Originally posted by Padeye
A pressure difference of as little as 1psi would put a load of several hundred pounds on a person's abdomen making it impossible to breathe. I think you are overlooking the point in the OP that the person would have a channel to outside air into their lungs, causing the internal pressure of the person's body to be equal to the ambient air pressure. Although I'm not sure--I'm open to hearing further reasoning on this.

There is another way to try this experiment that several foolhardy people do; they try to breathe with a garden hose while at the bottom of a swimming pool and find it impossible to doe so due to water pressuer at even a shallow depth I believe the claim but not sure I understand why this is so. Is it because the water pressure at that depth overwhelms the air pressure in the hose, and your lungs can't push out against the water pressure sufficiently to draw in the air? I have seen photos of "mermaid shows" where swimmers underwater breath from hoses, but I presume that the air is delivered under pressure.

And lastly--for the purposes of the physics of it, is being in an evacuated bag with a straw in your mouth really the equivalent of being subjected to the pressure of, for example, being deep underwater? (I think not, note my earlier post, but I welcome corrections.)

[Mangetout]

I don't think it is equivalent; normally, air pressure (~14psi) is balanced by an equal pressure from inside the body, when you dive underwater, but breathe through a (non-pumped) hose to the surface, your body is subjected to ~14psi plus the weight of the water above you, but the air you are breathing isn't.

Evacuating the spare air in the space between an effectively non-porous object and the plastic bag in which it resides cannot create any new pressure on the body (aside from the elasticity of the plastic) - it just enables the natural air pressure to push the plastic snugly against the skin; the balance of pressure is maintained.

[Q.E.D.]

Exactly, which is what I said at the outset. Divers have absolutely no problem breathing underwater with scuba equipment because the gas mixture they're breathing is higher than the water perssure exerted on them.

[Padeye]

I stand corrected on the vacuum packed Gimp being able to breathe. After some thought I realize the error in my logic. I still think it may not be easy to breathe if there is significant vacuum but this may be more to trying to stretch the membrane holding him down. Someone needs to do some research on this.

Originally posted by Mangetout
Are you sure that this effect isn't at least partly due to the porous nature of the wood - properly dried wood contains air between the fibres, this can be evacuated, causing a much greater pressure differential.

for example, I'm certain that you could vacuum-pack an inflated balloon and it would not shrink because you are not pumping out the air from inside it, however, if you were to take a sphere made of thin (but rigid) plastic and drill some holes in it, it would become possible to evacuate the gaseous contents of the sphere and vacuum-packing it would crush it.

It may seem like a paradox but I don't think the porosity of wood has anything to do with it. I think the perception comes from how we're used to atmopheric pressure. Try this on for size. Take three slabs of non-pourus rigid material. Leave one bare, cover one with a sealing coat of polyurethane and put one in a vaccum bag and evacuate all the air. All three have 1 atmophere of pressure exerted on the surface. What's the difference between the painted on coating and the vacuum bag? None really aside from the fact that the polyurethane probably has a molecule level bond to the slab.

[Mangetout]

Certainly it does seem a stretch that the air from within the structure of the wood could be easily vented, but I suppose over time it would; this wouldn't make the outdie pressure any greater, but the bag would try to 'push' into the minute cracks in the surface, which in itself would mean that the bag is 'tighter'.

I am certain though that if you took (say) two metal cans with airtight lids, drilled holes in one of them and vacuum-packed them both (individually), the one with holes in would be crushed, the one without would not.

[msmith537]

Originally posted by Rusalka
I worry why you would want to do something like this? Sealing someone in a bag like this would definitely KILL them, even with an "air straw".


I assumed it was for freshness.

[scr4]

I don't know about wood for composite construction, vacuum bagging is done to squeeze the epoxy from the cloth. You apply layers of carbon or fiberglass cloth soaked in epoxy onto a mold, and cover the whole thing with a plastic bag. When you connect a vacuum pump (you need a real pump, not a vacuum cleaner) the lowered air pressure pulls the epoxy out of the cloth. It isn't the plastic sheet pushing on the mold - there is no force acting on the mold itself.

With wood, I think Mangetout is correct in saying that it's the porous nature that makes it work.

[scr4]

Er, that should have been "I don't know about wood, but for compsite..."

Also I should clarify that the goal is not to remove all the epoxy, but to remove the excess and leave just enough to keep the fiber together.

[Mangetout]

Originally posted by scr4
When you connect a vacuum pump (you need a real pump, not a vacuum cleaner) the lowered air pressure pulls the epoxy out of the cloth. It isn't the plastic sheet pushing on the mold - there is no force acting on the mold itself.I don't think that is correct; there is no such thing as 'suck'* - what is happening is that the lowered air pressure inside the system allows the normal atmospheric pressure outside to press down on it and squeeze it - the plastic sheet really is pushing, because the atmosphere is pushing it.

Someone will link to Cecil's spaghetti article now, I'm sure.

[Padeye]

A difficult concept to grasp. Vacuum is not a thing but lack of a thing. Vacuum can no more exert a force than can "dark" or "cold." Dark should be pretty obvious. No one believes the old gag of a flashlight (torch for UK dopers) works by sucking up dark. "Cold" doesn't do anything but heat going from a hot place to a colder place can. This is why the second law of thermodynamics is far harder to understand than it appears.