>As a piece of folk lore, I also remember that the shop used to slowly fill
>the cylinders on the day prior to use, (something that was quickly and
>easily accomplished when there were only a few people in the country
>certified in Nitrox, and when there was still strong opposition to its use
>on the grounds that we would all die horribly and painfully!!<bwg>), and
>then regularly roll the cylinders to ensure proper mixing of the gas! :-)

This is of course totally valid and many people have 'natural' mechanisms
to mix the nitrogen & oxygen in air;
for instance, my wife never stops talking & the action of her tongue
ensures a smooth mix is breathed.
Personally, I favour the 'external influence' method of mixing my air,
simply accomplished by waving around
any suitable object near to my mouth, a glass of beer or bottle works fine
for me.
Cheers.............

Andy Johnson
Senior Product Support Specialist
UK HSC DASD
Basingstoke AL1C
Tel: 01256 34 1490 (Hunting Group)
Tel: 01256 34 1264 (Direct)
Mobile:07703 59 8282   Mobex:277 321
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