Welcome to ScubaBoard, an online scuba diving forum community where you can join over 100,000 divers from around the world discussing all things related to Scuba Diving. To gain full access to ScubaBoard you must register for a free account.
As a registered member you will be able to:
Participate in over 500 dive topic forums and browse from over 3,000,000 posts.
Communicate privately with other divers from around the world.
Post your own photos or view from 80,000 user submitted images.
Gain access to our free classifieds marketplace to buy, sell and trade gear, travel and services.
Use the calendar to organize your events and enroll in other members' events.
All this and much more is available to you absolutely free when you register for an account, so sign up today!
If you have any problems with the registration process or your account login, please contact the ScubaBoard Support Team.
Technical Diving SpecialtiesAdvanced and focused aspects of scuba diving with a technical training edge, ranging from caverns and caves, public safety diving, wreck penetrations to decompression diving and everything in between.
Got a question for all of the stateside folks there who are able to stay in the loop. Does anyone there have a LDS using balloon grade helium for their mixes. Obviously this has not created a large problem here since I am here writing this post and all my trimix buddies are still around also. What are the legal aspects and should the LDS disclose what they are using?
Got a question for all of the stateside folks there who are able to stay in the loop. Does anyone there have a LDS using balloon grade helium for their mixes. Obviously this has not created a large problem here since I am here writing this post and all my trimix buddies are still around also. What are the legal aspects and should the LDS disclose what they are using?
nothing about balloon grade helium is guaranteed or tested.. The risks go up the deeper you go.. just a little co or co2 can cause problems..
whats worse the cylinders are not vacuumed so anything can be in them..
I use grade 5.0 for all my mixing.. Its expensive about $219 per T in NY.. But I know exactly what is in it..
I would never use balloon grade ever, its too risky... too many unknowns.. The minimum I''d use is industrial, which is usually sucked to vacuum at leat once by any reputable gas supplier..
In many places all the grades come from the same source, but depending on the grade, what is done to the cylinders and if any additional filtering is done determines the purity..
I would never use balloon grade ever, its too risky... too many unknowns.. The minimum I''d use is industrial, which is usually sucked to vacuum at leat once by any reputable gas supplier..
i asked the same question. this pretty much sums it up.
It's worse than that. Some suppliers will add 20% O2 for liability reasons recognizing that some people at parties will use it for the donald duck effect when they talk. Balloons still float with a 20% 02, but party attenders won't pass out. Of course these same suppliers have no doubt realized that adding 20% O2 is also cheaper than straight helium. So if you are using balloon grade helium, what you may be getting may not be helium at all but rather some imprecise and undetermined mixture of heliox.
Industrial helium is normally refined by the same method and in the same equipment as more expensive grades of helium. So theoretically it is just as pure, but there is not the same quality control to ensure it stays that way. So quality will largely on the gas supplier. Having non-inert contaminants in their gas is not considered cool by many industrial users, so most (good) suppliers are pretty careful.
__________________
Life is not measured by the number of breaths you take, but rather by the number of moments that take your breath away.
Just to clarify something that was said earlier. When a tank is "vacuumed", (another way to put that is "a vacuum is pulled"), the majority of the gas which remains in the tank is removed from the tank via a vacuum pump. Vacuum pumps are capable of pulling deep vacuums and therefore leaving little or no undesired gas in the tank prior to filling filling with the desired gas.
This is what is done for the higher grade Heliums. The higher the grade, the deeper the vacuum that was pulled on the tank, the less residual gas was left in the tank prior to filling.
In our neck of the woods, Industrial Grade and Ballon Grade are the same thing. They say they don't add O2 to the ballon grade but who knows?
They don't pull the tank into vacuum for those grades, just bleed the tank to atmospheric pressure and fill. That means whatever gas was left in the tank at atmospheric, remains mixed with the Helium. Generally not a big deal in such small quantities.
But the only way to be sure is to get the higher grade Heliums. Considering the liability issues everyone is dealing with today, i wouldn't trust anything but the higher grades. Its not worth the money you save IMO.
Got a question for all of the stateside folks there who are able to stay in the loop. Does anyone there have a LDS using balloon grade helium for their mixes. Obviously this has not created a large problem here since I am here writing this post and all my trimix buddies are still around also. What are the legal aspects and should the LDS disclose what they are using?
Do not use "balloon grade" helium in diving mixes!
There is a chance that "balloon grade" is safe, but the only rule for it is "it will float a balloon." Period. While y'all are getting away with it for the time being, sooner or later it will bite you square in the tail.
Don't do it.
Rick
__________________
"You can have peace, or you can have Freedom. Don't ever count on having both at once." (Heinlein)
"... they saw the deeds of the LORD, his wondrous works in the deep." (Ps107:24)
Last edited by Rick Murchison; December 9th, 2005 at 12:18 PM..
Thanks for the answers so far. I understand that each and every dive using a questionable gas is playing russian roulette. I have never would have worried too much about the 02 content of balloon grade helium had I known I was diving it. I analyze gas at too many points. What concerns me is the trace gasses (contaminants) that may be present. Does anyone know of any specific requirement for the LDS to disclose information on the gases they are providing? I know that I am reaching here, but we are in the dark ages out here. By the way, what led to this discovery was a bottle of argon in the helium rack. I haskeled down bottles one and two in the rack and was shifting to bottle three when checking the lable revealed that it was argon in the same color bottle. What an accident report that would have made.
While y'all are getting away with it for the time being, sooner or later it will bite you square in the tail.
Rick I know what you mean. Normally I blend my own brew, but having just retired from the navy and moved off base my banks are not back up yet. We have one dive shop on this island who provides helium and one gas supplier. I buy industrial grade gas for (dont laugh shipping to the south pacific) 90 cents a cubic foot. Our one dive shop moving helium is selling balloon grade at 1.25.... Maybe I should bring in a nuvair compressor and start my own gas station.
Some suppliers will add 20% O2 for liability reasons recognizing that some people at parties will use it for the donald duck effect when they talk. Balloons still float with a 20% 02, but party attenders won't pass out.
If any oxygen is added at all, it would have to be quite a bit less than 20% for a balloon to float.
.8 cubic feet of helium would weigh about 0.008 pounds.
.2 cubic feet of oxygen would weigh about 0.0166 pounds.
At a pressure of 1.1 ATA, this mixture would occupy about .91 cubic feet.
The .91 cubic feet of air being displaced would weigh about .068 pounds.
That leaves .04 pounds of force to hold up the balloon itself plus anything attached to it. That is quite a bit less than an ounce and any other contaminants in the gas would reduce it further.
Linear Mode
