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Author Topic: Why do helium balloons to lose lift after a few days?  (Read 24349 times)

Hadrian

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Why do helium balloons to lose lift after a few days?

and how can you stop it?

Heliotrope

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Re: Why do helium balloons to lose lift after a few days?
« Reply #1 on: 07/12/2006 22:29:35 »
The helium percolates through the skin of the balloon thus reducing the amount inside to provide lift.
It also escapes through the imperfectly sealed end of the balloon.
The ballons are usually made of mylar so the rate is low but helium is such a small atom that it's hard to keep it in anything for any length of time and especially in a 50 cent balloon.
If you blow up a normal rubber balloon with helium it only lasts for a few hours.

daveshorts

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Re: Why do helium balloons to lose lift after a few days?
« Reply #2 on: 07/12/2006 23:22:10 »
The mylar ones tend to be shiny because they have a thin layer of aluminium evaporated onto it. Alumninium has much smaller holes than rubber so it diffuses through this a lot slower. It also means that the pressure in the balloon is a lot lower (as the mylar isn't elastic) so the helium isn't being squeezed out.

NewBill

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Re: Why do helium balloons to lose lift after a few days?
« Reply #3 on: 08/12/2006 07:16:42 »
Is there a material that is better than mylar?

Heliotrope

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Re: Why do helium balloons to lose lift after a few days?
« Reply #4 on: 08/12/2006 18:39:37 »
There are lots of materials that are better than mylar.
Glass for instance. Or steel.
Most of them are much heavier than mylar so it doesn't matter how much helium you put inside them they still won't float.

neilep

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Re: Why do helium balloons to lose lift after a few days?
« Reply #5 on: 09/12/2006 17:51:24 »
What I want to know is why after a few days when the balloon may still have some helium left in it, does it no longer make the tone of your voice high !!....or is it just air that is left in the balloon ?

Hadrian

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Re: Why do helium balloons to lose lift after a few days?
« Reply #6 on: 09/12/2006 19:33:52 »
What I want to know is why after a few days when the balloon may still have some helium left in it, does it no longer make the tone of your voice high !!....or is it just air that is left in the balloon ?

helium is helium even after a few days

neilep

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Re: Why do helium balloons to lose lift after a few days?
« Reply #7 on: 09/12/2006 19:50:40 »
What I want to know is why after a few days when the balloon may still have some helium left in it, does it no longer make the tone of your voice high !!....or is it just air that is left in the balloon ?

helium is helium even after a few days

Are you sure ?...cos why does the tonal joy go when deeply inhaled from old helium balloons ?..cos me is wondering , like Heliotrope says, that the helium element escapes leaving just air ....maybe....perhaps.....me wonders !!

..whajafink ?

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Re: Why do helium balloons to lose lift after a few days?
« Reply #8 on: 09/12/2006 21:10:15 »
Perhaps the amount of helium is not sufficent to change the pitch anymore!
QUESTION!! I have always been curious as Quite a while back I read an article about helium and children! Can it really cause the lungs to explode? or some thing like that! They said it was extremely dangerous to allow them to fo as too much could basically rupture the lungs! Seeme odd. How would one suck in more then the lung could handle! Does Helium expand or become different? I don't get it if it is true!

neilep

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Re: Why do helium balloons to lose lift after a few days?
« Reply #9 on: 09/12/2006 21:28:50 »
Cripes !!..me wants an answer to this too as I always let my kids breathe in helium luff when we have it....Of course..it means having to pull them down from the ceiling afterwards but they enjoy it !!






*THIS SITE DOES NOT CONDONE THE INHALATION OF HELIUM BY CHILDREN UNTIL THIS MATTER IS RESOLVED*

Karen W.

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Re: Why do helium balloons to lose lift after a few days?
« Reply #10 on: 09/12/2006 22:19:50 »
Dang, I thought you might know!! LOL Geesh! Does anyone else know?

ukmicky

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Re: Why do helium balloons to lose lift after a few days?
« Reply #11 on: 09/12/2006 22:22:13 »
Quote

QUESTION!! I have always been curious as Quite a while back I read an article about helium and children! Can it really cause the lungs to explode? or some thing like that! They said it was extremely dangerous to allow them to fo as too much could basically rupture the lungs! Seeme odd. How would one suck in more then the lung could handle! Does Helium expand or become different? I don't get it if it is true!

Helium atoms are less tightly pack together than air arnt they,i thought thats why the pitch of your voice goes up as sound travels faster through a denser gas.

If so wouldnt an increase of temperature caused by being inside your lungs cause a lung full of helium to expand much more than a lung full of air.

Of course i'm probably totally wrong about all the above, and am just trying to act a lot more brainy than i really am. :)
« Last Edit: 09/01/2007 04:02:49 by ukmicky »

Karen W.

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Re: Why do helium balloons to lose lift after a few days?
« Reply #12 on: 09/12/2006 22:33:04 »
That makes perfect sense to me Michael me friend! I have to say I must rely on all of your brains around here as sometimes mine slips away and I find it hard to bring it back and make it work properly again!! LOL

Karen W.

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Re: Why do helium balloons to lose lift after a few days?
« Reply #13 on: 09/12/2006 22:46:43 »
Here is a discussion of this from a site I found, nothing conclusive as far as I can see, but some of the information was interesting none the less! Sorry its so long!

"From: "Chris Jackson" <duncan@frii.com>
To: "Jack Finch" <pezzo4balloons@earthlink.net>
Subject: Re: Helium Question????
Date: Tue, 26 Jun 2001 10:08:23 -0600

Greetings, All.

Jack Finch wrote:

> When I make helium balloons at the mall I warn the kids against trying to
> breath the helium in an effort to sound like Donald Duck. When they ask
why
> I tell them that is is not good for them but I am not sury whe. What are
the
> hazards of breathing helium?

The responses that were posted to this list (that is: the ones that I
recieved with my latest BHQ digest update) were *all* either misinformed
(i.e. "urban legend") or else downright *WRONG* in their conclusions! I've
no doubt that many if not most of the folks on this list understand the true
(and scientifically sound!) dangers about inhaling helium,... this posting
is intended to "tell the truth, the whole truth, and *nothing* but the
truth!" about inflating helium!

Re: Dave Barry's article...

From this post, I must conclude that the child in question was breathing
"in" nothing but industrial grade helium, with no pauses to allow oxygen to
reach his system. This child was "drowning" in helium.  The human body needs
a certain amount of oxygen to continue to function. (i.e. LIVE!) The sole
*major* danger of inhaling helium is: Doing so without breathing oxygen for
too long!


Terry, "Gitsy" Basco wrote:

>I explain to them that helium can kill them.  First... it, as the article
that was just posted, has no oxygen.. do it enough times in a row.. and that
is not as many as you would think, and you can literally be suffocating
yourself and not know it. It is like someone holding a bag over your head..

BINGO!  Too much is *not* a good thing.  Breathing in nothing but helium
will kill you as easily as if you were breathing in nothing but CO2.  Pure
helium is O.K., *BUT* only if you breathe in some oxygen in between each
'hit' of pure helium.

One breath will *NOT* cause harm, several breaths in a row will have an
effect that is similar to smoke inhalation.  No Oxygen means that your brain
is being starved.

>Also, if you get hold of helium straight from the tank instead of a balloon
there is
a potential of exploding your lungs.

A "Potential", yes.  A remote possibility.  Inhaling straight from the tank
is a *major* danger. (see below)  Inhaling from the regulator (the device
that *seriously* lowers the output pressure) lowers this danger, but the
danger is still there.  Inhaling from an inflated latex balloon makes this
"exploding your lungs" story nothing but an "Urban Myth"! (i.e. a bald-faced
LIE!)

 >There is something like 2000 lbs of
pressure (don't quote me on the exact amount) in a helium tank.

I've dealt with several different companies, with different descriptions of
what
constitutes a "full" helium tank, and their products range from 1800 PSI to
2400 PSI. HOWEVER, the only way to expose oneself to this kind of pressure
is to stick your mouth directly on the valve at the top of the tank and open
it.  (i.e. no regulator.)  This kind of pressure *is* dangerous, and
difficult to control. If you tried inflating a balloon directly from the
tank, you would most likely either burst it or underinflate it.  That's why
engineers designed and built the pressure regulators that are used today.

> Enough so that if it was dropped without the protective cap on and the
valve was
broken off it would shoot literally like a torpedo. Hard enough to go thru a
wall.  I have heard some great stories of things like this happening in the
place they sell the helium.

Hmmm... I can see this happening, *very* rarely!  It would take a
combination of extrordinary circumstances and a total disregard of common
sense safety procedures.  In other words, it would be hard to do this
deliberately, much less accidentally!

>Helium is also used in welding.

Sometimes, occasionally, yes.  It is used when a non-chemically reactive
environment is needed. (very rare, and only for specific, unusual jobs.)
the vast majority (99%+) of welding jobs don't require such extremes.  An
Oxygen/Acetelene mix in an open-air environment is usually sufficient.

>If you are going to have a helium tank in your home.. I rent one for a
minimal fee to have it here whenever I need it...  you are supposed to
either chain it to a wall, or purchase a safety cart, that it can be
strapped to, so it can't accidentally tip.

This is one of the common-sense safety procedures mentioned above.  You've
got a long, skinny, *heavy* object balanced on one of the narrow ends.  Of
course you should take precautions to prevent it from tipping.  This rule
also applies to things like bookcases and home entertainment units.  You are
much more likely to be injured when this 60lb+ chunk of steel falls over and
lands on your foot.

Ian Lloyd wrote:

>Helium is taken up by the body faster than, and in
place of . oxygen.

Um,... er,... ah.... NO!  Sorry to be so blunt, but the above statement is
just plain untrue!  Check your high school chemistry book and you will find
that Helium is *not*, in any way shape or form, chemically reactive.  Your
body does *not* absorb it in place of oxygen, it cannot!  That is a physical
impossibility.  Read on.

> If the practice is not continuously repeated there isn't
a great deal of danger BUT why would anyone in their right mind encourage
(or not discourage) children from putting chemicals into their bodies,
particularly by inhaling?

A good point.  Personally, however, if a child is going to inhale something
for pleasure, then I would rather it be helium, or preferably a 80/20 mix of
helium and oxygen.  Helium is non-toxic, non-carcinogenic, non-addictive,...
in fact that helium/oxy mix is actually safer to breathe than the
smog-filled air that blankets most major cities. (Denver, LA, New York,
etc...)

The biggest danger appears when someone breathes pure helium.  This could
lead to suffocation due to lack of oxygen.  Its not a question of the helium
"displacing" or "replacing" the oxygen in your bloodstream, if there is no
oxygen there to begin with, then *there* is your problem. The same problem
would occurr if you inhaled pure nitrogen, pure neon, or any other pure gas
that dosen't contain oxygen.

You want to avoid the suffocation danger?  Teach the kids to take a deep
breath of fresh air in between each breath of helium. That's all it takes to
avoid the suffocation danger.  Period.

>There is a danger in taking the use of something in one situation and
extrapolating that into its safe use in an entirely different situation. If
divers use helium or nitrox at depth I beleive the same mix would be lethal
at the surface ( I may be wrong, it's happened before, once)

Yes, you are incorrect on this.  (sorry, my friend.)  Right now, sitting in
front of your computer, reading this message, you are breathing a (roughly)
80/20 nitrox mix.  80% nitrogen, 20% oxygen. (roughly...) Its more commonly
known as "air".  There are some impurities, CO2, trace gasses, smog
particulates, even <gasp!> a bit of helium!  That's your standard atmosphere
here on good old Earth.  Not at all lethal at the surface.

Divers carry a nitrox mix with them for a reason... Too *much* Oxygen in the
bloodstream can be dangerous.  That's right, too *much* is bad for you.  If
your body overloads on Oxygen, you get a sensation similar to drunkeness.
You get very relaxed and euphoric.  In a situation where you only have a
limited amount of time before you must surface this can be a real danger.

When doing long deep dives, it is preferable to use a 80/20 Helium/Oxy mix.
This is safer due to the dangers of Nitrogen Narcosis.  For more info, click
here: http://www.britannica.com/seo/n/nitrogen-narcosis/

Bottom line,... breathing helium is *not* dangerous, unless you fail to use
common sense.  Common sense rules: 1) Don't put your mouth on a 2000psi gas
source, vent the gas into something safer, like a balloon. 2) Don't breathe
pure helium for more than a few seconds, take a breath of fresh air
inbetween each breath of helium.

I challenge any and all to show me a case of someone who followed these
common sense rules and still came to harm.

Don't blindly accept the horror stories, get the truth, the *WHOLE* truth,
and nothing but the truth.  The whole truth will usually unravel the "urban
myths".

Chris Jackson
Ft. Collins, CO."

How much of these facts are correct and how much garbage?


Soul Surfer

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Re: Why do helium balloons to lose lift after a few days?
« Reply #14 on: 09/12/2006 23:18:36 »
Helium is OK but hydrogen isn't.  Many years ago when life was simple and asbestos was something we used to put things on to braze them in the lab or use to fix screws in walls and  when we were mixing up various witches brews using a fume cupboard was for wimps and almost everyone smoked everywhere, Hydrogen was cheap and used for all sorts if things and helium was very expensive. We sometimes amused ourselves by breathing in hydrogen and going all squeaky it has just the same effect a helium  but this is incredibly dangerous because one tiny spark will result in a really nasty death of fried and exploded lungs.
« Last Edit: 09/12/2006 23:22:09 by Soul Surfer »

Karen W.

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Re: Why do helium balloons to lose lift after a few days?
« Reply #15 on: 09/12/2006 23:21:59 »
Pardon me, you mean the Helium or the hydrogen?

rosy

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Re: Why do helium balloons to lose lift after a few days?
« Reply #16 on: 09/12/2006 23:23:11 »
No, really, be very careful breathing helium.. it's not in itself toxic (as far as I know...) but the received wisdom amongst health and safety types in the scientific community is that one full breath at less than 10% oxygen (half the normal level in air) will probably kill you.. essentially the "drowning" argument above.
This means that if you managed to breathe in 50% helium 50% air you'd quite likely be in trouble (as that would take the concentration of air down to 10%. It would probably be fairly difficult to achieve this breathing from a balloon, but I wouldn't be keen to take the risk myself and certainly wouldn't encourage a child to do so. The point above that high oxygen concentrations are bad is entirely valid but misplaced. Just because too much of a thing is bad don't mean you can live without it entirely.

Basically, don't breathe pure helium under *any* circumstances. You would be very lucky not to die.

Incidentally, someone in the thread above suggested that helium atoms packed closer together than other air molecules... not so. Atoms/molecules in gases are, to a good approximation, spaced the same (at the same temperature and pressure) regardless of whether the gas is oxygen, nitrogen, CO2 or helium.
Since one helium atom weighs a lost less than a molecule of more or less anything else (except hydrogen gas), helium gas is the lightest non-explosive gas you can get. Hence why helium filled balloons float.

Soul Surfer

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Re: Why do helium balloons to lose lift after a few days?
« Reply #17 on: 09/12/2006 23:28:03 »
Helium is inert and safe but almost all mixtures of hydrogen and air are violently explosive.

OK neither of them are any good for breathing and you need oxygen evenually but the body will usually sort this out   itself by telling you that you need to breathe.  that's eher carbon monoxide (re recent deaths)is so insidious because it acts like an anaesthetic and you dont relise you are dying unril it is too late

Karen W.

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Re: Why do helium balloons to lose lift after a few days?
« Reply #18 on: 09/12/2006 23:42:23 »
Holy  crud that is very scary!!! Neil Be careful with those kiddies! ( I know you are!)

Yikes isn't that a horrible thought!

chris

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Re: Why do helium balloons to lose lift after a few days?
« Reply #19 on: 10/12/2006 12:35:36 »
Carbon monoxide (CO) is dangerous for a different reason than the threat from asphyxiation caused by filling the lungs with non-respirable gases.

Unlike helium, nitrogen or even hydrogen, when CO meets haemoglobin it forms a tight complex called carboxyhaemoglobin.

Under normal circumstances, haemoglobin links up with molecules of oxygen to form a substance called oxyhaemoglobin. In the tissues, where the local oxygen concentration is low (because cells are picking it up and using it), the oxygen molecules separate from the haemoglobin and are used by cells to produce energy. This regenerates the haemoglobin, which returns, via veins, to the lungs for re-oxygenation.

But unlike oxyhaemoglobin, the carboxyhaemoglobin formed by the interaction of carbon monoxide and haemoglobin is very stable and only infrequently do the two molecules separate again. In this state it also cannot carry oxygen.

So someone breathing carbon monoxide will progressively turn their haemoglobin into carboxyhaemoglobin, reducing the amount of functional haemoglobin capable of carrying oxygen to the brain and tissues. It's analogous to replacing someone's blood with water - although there are cells being pumped round they cannot carry any oxygen.

As a result people become unconscious. It's rather like flying in an aeroplane at great altitude and the cabin depressurising. Those oxygen masks drop down because without it there would be too little oxygen available to supply the brain's needs, and you'd black out.

Can you remedy it? Thankfully yes. If a person with carbon monoxide poisoning is given pure oxygen to breathe you can slowly dilute off the carbon monoxide and at the same time increase the supply of oxygen reaching the brain and tissues by forcing more oxygen to dissolve in the blood plasma.

Chris

ROBERT

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Why do helium balloons to lose lift after a few days?
« Reply #20 on: 08/01/2007 15:38:42 »
Basically, don't breathe pure helium under *any* circumstances. You would be very lucky not to die.


The 2006 Darwin Award winners should have taken your advice Rosy

Quote
And the 2006 DARWIN AWARD Winner is...

HIGH ON LIFE: "Take a deep breath..."

(3 June 2006, Florida) Two more candidates have thrown themselves
into the running for a Darwin Award. The feet of Jason and Sara,
both 21, were found protruding from a deflated, huge helium
advertising balloon. Jason was a college student, and Sara
attended community college, but apparently their education had
glossed over the importance of oxygen.

When one breathes helium, the lack of oxygen in the bloodstream
causes a rapid loss of consciousness.  Some euthanasia experts
advocate the use of helium to painlessly end one's life.

The pair pulled down the 8' balloon, and climbed inside. Their
last words consisted of high-pitched, incoherent giggling as they
slowly passed out and passed into the hereafter.

Sheriff's deputies said the two were not victims of foul play. No
drugs or alcohol were found. The medical examiner reported that
helium inhalation was a significant factor in their deaths. A
family member said "Sara was mischievous, to be honest. She liked
fun and it cost her."

http://www.darwinawards.com/newsletter/200701.txt

 

ukmicky

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Why do helium balloons to lose lift after a few days?
« Reply #21 on: 09/01/2007 03:59:17 »
Incidentally, someone in the thread above suggested that helium atoms packed closer together than other air molecules... not so. Atoms/molecules in gases are, to a good approximation, spaced the same (at the same temperature and pressure) regardless of whether the gas is oxygen, nitrogen, CO2 or helium.
Since one helium atom weighs a lost less than a molecule of more or less anything else (except hydrogen gas), helium gas is the lightest non-explosive gas you can get. Hence why helium filled balloons float.
sorry i should have said helium is less denser
« Last Edit: 09/01/2007 04:01:51 by ukmicky »

 

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