You’d think if we stopped wasting it in balloons we could probably double that.
[quote=“Dr.Strangelove, post:37, topic:923423, full:true”]
… Oh, and I suppose it is over 4 orders of magnitude more potent than CO2 as a greenhouse gas, so keep it indoors.
[/quote]Anything gaseous indoors eventually ends up outdoors, in the atmosphere. (Very few of us live in absolutely air-tight buildings.)
I have worked with Hydrogen (and helium for that matter) for last 20 years or so in Industrial settings, There is a lot of paranoia around Hydrogen primarily from the Hindenburg but a lot of it is misplaced. So the Axis used hydrogen because helium was cut off, well so what; Axis also used Hydrogen to make synthetic fuels (Fisher Tropsh) to power all the war machinery. Their oil supply was cut off too - all that hydrogen didn’t cause disasters.
When fuel cells came out about 20 years back, the biggest concern for hydrogen cars was explosions. But all of the Hydrogen cars crash tested came out with flying colors . Hydrogen Archives - Green Car Future
The thing which is often overlooked is that Hydrogen is the smallest molecule around and the molecule moves around incredibly fast. If you have a hydrogen leak, say in a warehouse - it will escape very quickly and the concentration will be same everywhere in the warehouse - very quickly. Hydrogen doesn’t pool at all.
Sure Hydrogen is flammable, but we understand with a high confidence level as to how to mitigate the risks. The controls are mature.
The gas that really scares me is oxygen. None of the shuttle or other rocket disasters are from hydrogen but many many are from oxygen. We have had incidents where liquid oxygen was spilled on an asphalt road and the road exploded. A worker working by an oxygen vent , went outside the plant for a smoke and got burnt to death. His clothes had absorbed oxygen. Even stainless steel pipe carrying oxygen will burn merrily if there is a sharp bend installed. The pipe itself burns with firework quality displays of iron, chromium and nickel burning with full color display.
Easy solution; just empty your swimming pool and fill it with SF6. It’s so dense it’ll stay in there for a long time. Just make sure everyone’s wearing SCUBA gear. Definitely don’t want to end up with a couple dozen dead children at the end of the birthday party. Small price to pay for floaty balloons, though.
As an aside:
It is fun to read Derek Lowe’s Things I Won’t Work With articles (he’s a chemist). One is about chlorine trifluoride. He relates an accident spill which burned through a foot of concrete and then a meter of sand below that.
From the link above:
It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.
But despite that, there were two explosions at hydrogen fuel facilities in June of last year: one in California at a hydrogen production plant and one in Norway at a hydrogen fueling station. Wikipedia lists 9 incidents (including those two) involving hydrogen since the beginning of 2018. While all those were probably not with hydrogen intended for the retail market, it still seems like a rather high rate of incidents for a market still in its infancy. I suspect that market is not going to survive.
forgot to give the link to Wikipedia in the post above: Hydrogen safety
That quote is in fact from John D. Clark (it says so on the web page).
The oxygen safety video is here.
Much of the Wiki Links are for Oil & Gas / Chemicals manufacturing industry. If you look at the accidents, the impacts to human life are minimal. My guess is that Natural Gas related incidents or airplane related incidents would be in the same or higher severity over the same time period.
Since Haber made the first Ammonia plant , hydrogen consumption has only been increasing. Hydrogen is used to make Ammonia - which is the predominant way crops receive nitrogen. Unless humans stop eating, the market for Hydrogen will always be there.
Sorry…the whole article which I linked to was written by Derek Lowe and he included that quote from John D. Clark in his article.
My apologies for not making that clear.
I meant the retail market selling hydrogen to motorists who have fuel cell vehicles.
Yes, if you listen carefully you can hear it whooshing over your head on its way out 
.
Does that mean that the helium that accumulates in underground cavities consists of alpha particles that were emitted as a result of radioactive alpha decay and then captured two electrons somewhere along the way?
Though I certainly don’t recommend filling your house with it, it is true that sulfur hexafluoride is non-toxic, so dense that it’ll stay in an open container, float an air-filled balloon (or even foil boat!), and make your voice super deep.
It’ll also suffocate you if you if you happen to be in a low, enclosed place and it collects there, so… maaaybe not suitable for kids.
Yes. The emitting atom has two extra electrons of course; the alpha particle will likely pick up its electrons from somewhere else, but eventually the electrons redistribute so that the charge is balanced out. The electric force is powerful and it usually doesn’t take long for the charges to move around and everything to become electrically neutral again.
Thanks - to be clear, I wasn’t doubting any of that, my reference to whooshing was specifically the part where you said it would be best to keep it indoors to avoid it becoming a greenhouse gas. Clearly, where you choose to keep it isn’t going to affect things much in this regard.
Yes. Upthread I pointed out that most helium in the universe comes from the Big Bang and secondarily from stellar fusion, but none of the helium on Earth comes from those two sources. The reason is that helium doesn’t form compounds, so it will always be a gas, including in the early solar system. And the Earth’s gravity isn’t strong enough to hold onto helium.
Note that the source of all the inert gases on Earth are from radioactive decay for basically the same reason. None of them naturally form compounds, so they’ll be gases and thus wouldn’t be present except in trace amounts in the planitesimals that made up the planets. All the argon in the atmosphere, for example, comes from radioactive potassium-40. You’ve probably heard of potassium-argon dating. That’s works because of that particular form of nuclear decay.
Yup. If we were a more sensible species this would be the obvious first step for dealing with the problem: stop wasting the stuff.
Yay! I think the older blog posts were completely off the internet for a while, but I see now they’re not only online, but there are new ones. Still, the one you linked to, “Sand Won’t Save You This Time” is the best one.
as mentioned above, when divers go very deep in the ocean they breathe helium and oxygen because nitrogen can cause problems. And yes, they sound funny when they talk.