If that's the case, why can people breathe helium out of balloons and not immediately pass out? Is there oxygen mixed in?
Posts: 3546 | Registered: Jul 2002
| IP: Logged |
quote:If that's the case, why can people breathe helium out of balloons and not immediately pass out? Is there oxygen mixed in?
That's one of the notices that we got on a regular basis. Praxair is the only producer of helium in north america, so when someone dies from the use of our product we get an internal memo. But it's not widely publicized outside of the company.
Most of the people who die from breathing helium die from a related injury. They fall and hit their head or break their neck.
The reason many people successfully breathe and talk with helium is a question of ratios. You never fully empty your lungs when you exhale. And since you have to breath out of a balloon to get the helium, you only take a small breath. Oxygen is normally about 20.7-20.9% of air, but you can survive nicely down to about 19.5% oxygen in whatever gas you're breathing.
In order to get below 19.5%, you have to work at it. Most people will feel light headed after talking with helium for a little while, and stop doing it. But people that exhale very deeply and then take a long draw on a balloon are likely to pass out. And when it happens, it happens fast.
The MSDS for helium explains that helium is an asphyxiant, but since it isn't sold for internal use, there aren't big warnings all over the place explaining the danger. However, when someone uses the helium voice on TV, Praxair's lawyers are all over them. Federal express pulled an ad after they were contacted, for example.
I filed an idea memo with praxair the year before I left that they should sell "balloon gas" with 79% helium and 21% oxygen. Since helium is way more expensive than oxygen this would save them money. They might even be able to charge more for it. And it would eliminate the possibility of liability from asphyxiation. One of the responses that I got was that by doing so, it might be seen as a tacit acceptance that people would breathe a gas mixture that wasn't intended for internal use. I haven't heard anything about it since I left the company.
Posts: 3735 | Registered: Mar 2002
| IP: Logged |
OK. I put the pineapple can (half full), covered with a baggie, in the fridge way back in July. Now it is September -- and still no can etching action. There is some funky growth going on the surface of the pineapple, though.
I check it once a week. The can is intact.
Glenn -- maybe you were mistaken? Maybe it wasn't pineapple, but something more can-corroding?
I'll continue to watch and wait, but I'm getting a little bored and impatient already.
Posts: 10397 | Registered: Jun 2005
| IP: Logged |
posted
Another possibility: different brands of pineapple, and therefore both different pineapple (acidity, sugar level, even precise variety of fruit) and different cans. Some brands treat the insides of their cans with various anti-corrosion substances.
Of course, Glenn's could have been a mutant can.
Posts: 32919 | Registered: Mar 2003
| IP: Logged |
posted
Glen, it's been 6 months, and my pineapple can STILL hasn't etched itself in half. But the pineapple has metamorphed into something-that-used-to-be-but-is-now-no-longer-pineapple. A kind of brown sludge. Periodically, someone will happen across the can, with it's little baggy perched on top, peak in, and say "I'M TOSSING THIS!", but I have always stopped them, swearing that it is an Experiment In Progress.
But I'm giving up. You must have been dealing with a different kind of pineapple. Or a different kind of can.
Posts: 10397 | Registered: Jun 2005
| IP: Logged |
quote:Originally posted by Glenn Arnold: But I once left a half a can of pineapple out and when I came back the can had been etched in two at the liquid level. When I picked it up I had an empty (but extremely sharp) ring of metal in my hand, and the pineapple was still in the half can on the counter. (literally half a can)
quote:Originally posted by Glenn Arnold: Um, the can was in the refrigerator, and I honestly don't have the faintest idea how long it had been in there.
Hmm. He DOES change his story. At first it had been left out. Later in the thread, it's in the refrigerator.
In any event, mine is ziplocked into a biohazard bag in the trash can behind the house.
Posts: 10397 | Registered: Jun 2005
| IP: Logged |
Printer-friendly view of this topic
![[Big Grin]](biggrin.gif)
