Helium prices ...

[helodriver87]

Are you guys not concerned about breathing "balloon grade" Helium specially at depth?

Depends on the supplier. Balloon grade can be anywhere from the upper 80% range to 99.98%. Oxygen is typically added for balloon applications. As long as you know what you have in the cylinder, you can blend appropriately.

 

[rjack321]

At least here on the left coast there's no such thing as balloon grade. Its either "industrial", "USP" or UHP

 

[CAPTAIN SINBAD]

So the only difference between breathable and balloon grade is that ballon grade is diluted with oxygen? That is a breathable impurity.

 

[RayfromTX]

It varies. In my area balloon grade(bottle says balloon grade) has always been the same as uhp as it all comes from the same big tank but I have some concern that with higher prices that we may see some dilution for cost savings while claiming it is for safety in case of kids breathing from balloons. Testing isn't hard especially for O2. Balloon grade with O2 added would make blending hypoxic mixes a challenge.

I seriously doubt they would add argon or anything else to save money. They do after all simply charge whatever they have to based on the cost to them. It is a niche product and there isn't really a big incentive to have a different supply chain for gas going to the florists et al.

I could be completely wrong. My experience is limited.

I don't supply gas outside my family.

I define family.

 

[taimen]

So the only difference between breathable and balloon grade is that ballon grade is diluted with oxygen? That is a breathable impurity.

No, not necessarily. It is what your gas supplier defines. I don't think "balloon grade" is an official purity class anywhere.
In my country, it is 99% Helium, but the provider does not guarantee by any means what the other impurities are or are not. It is not considered breathable here, mostly because there is a fear (real or not) that the impurity could possibly be something harmful, like acetylene, carbon dioxide etc.
They are not adding oxygen, or anything else to save money, but it can be recaptured helium that may or may not have impurities. They may also use re-use cylinders that may carry over some impurities to the product.

I have seen a product labeled "diving Helium" by Air Liquide in France, I think that was 99.5% Helium but obviously in such a product the impurity is safe to breath.

In Finland we are sold "N46" for diving, that means it is at least 99.996% pure helium. It is the lowest grade of "ultra pure".
In areas where specific diving gases are sold, the product is probably the same as something else, but the different labeling may be for tax reasons. Like our "diving oxygen" is medical oxygen, but is sold with higher value added tax as medical use has lower tax.

 

[Miyaru]

This is the designation of helium I'm familiar with:
Helium 4.6 -> 4 nines and a six -> purity 99.996%
Helium 5.6 -> 5 nines and a six -> purity 99.9996%
5.6 is almost twice as expensive as 4.6

Balloon-grade helium is usually anything up to 98%, I've been told it's reclaimed helium that was used in MRI scanners (although I can't explain it, since He doesn't bind to anything it stays clean and wouldn't need replacing. Does it?).
Anyway, the remaining two (or more) percent can be anything. Not necessarily oxygen. 2% CO or CO2 will switch your lights off (at any depth).

 

[Storker]

since He doesn't bind to anything it stays clean and wouldn't need replacing. Does it?

It doesn't bind, but it mixes.

What was in the system they recovered the He from? What was in the lines of the equipment they used to recover the He? What was in the tank they filled with the recovered He? You can't know, and nobody else can either unless the equipment and tanks are scrupulously cleaned and you have some way to guarantee that there wasn't some crap in the system where they filled the He before it was recovered.

It's knowing, not just believing which costs.

 

[Miyaru]

Good point @Storker, and I don't have the answers to your questions. I did ask my supplier about balloon helium, and he answered me that it was reclaimed helium. Good enough to make a balloon rise.
The cheaper tanks one can buy specifically for inflating balloons, usually have a helium percentage from 30% to 50%. Useless for diving.

 

[taimen]

I've been told it's reclaimed helium that was used in MRI scanners (although I can't explain it, since He doesn't bind to anything it stays clean and wouldn't need replacing. Does it?).

During normal operation current MRI scanners have quite minimal helium loss.
Quenching the magnetic field (occationally for maintenance and rarely for emergency) involves heat dissipation and boiling a lot of helium.
The helium in MRI has to be extremely pure. Gas captured from MRI machines would most probably be safe to breathe. Selling it as safe and taking responsibility is another story.

 

[RayfromTX]

Grades of helium: the differences and uses