The ones that say 99% purity are fitted with a BS3 valve which apparently means they are non toxic??
Many are 'oxygen-free' but I suspect contain a high proportion of CO2 which will give suffocation effect.
Anyone found a reliable source?
The alternative I have found is 90% helium but I suspect this would have enough oxygen in it to make it difficult to suffocate.
Many are 'oxygen-free' but I suspect contain a high proportion of CO2 which will give suffocation effect.
Anyone found a reliable source?
The alternative I have found is 90% helium but I suspect this would have enough oxygen in it to make it difficult to suffocate.
