From the above posts it sounds as if thats gonna vary from company to company. Swims pretty sure that theres more different gasses then colors of the rainbow, so going by color doesnt sound too smart. Unless theres a governing authority/body at the regional or state level. Swiy could check into that. Best bet would probably bee to talk to someone who makes a living off of welding first.
Are the tanks grouped by color? If so, what are the reasons/characteristics of each color etc... Actually it does make sense that thered bee some governing rule regarding this, although the adapters differ for different gasses (or thats the way swim understands it), it would make sense as a cautionary measure to have different colored tanks especially for welders when they are mixing gasses. Swiy can ask a local mart employee who handles blowing balloons where they get their tanks, and if they are always the same color for helium 'cause you saw one that was a different color etc... Build up as much info as you can, and then ask yourself "what is a reason why someone in that company would explain their coloring system (or labeling system) to someone?" And then work up from there.
Dunno...?..
Another possability would bee to watch/find out where an employee (preferably one who directly handles the tanks in some fashion) after work, likes to drink (the idea is to ask the question when and how it wont seem suspicious). Friendly conversation->where do you work->me and my brother had an argument about how those tanks are colored etc...
Kinda far-fetched maybee, but its an idear.
"I £ my dog"
-Buddha
