Justin699:The way I see it, the shop is doing a service of putting the air in the tank, not selling the air (I would imagine that could get into all other sorts of issues since air is a natural resource) .
Im with Jonnythan on this one, Air is a resource, natural or not it doesnt matter. the dive store modifies this natural resource theus compressed air is a product. You walk out with a modified natural resource which by definition is a product because it was produced.
Unless of course you take your own uncompressed air to the dive shop in large to be compressed, then they are selling you the service of compressing your own air and therefore you should not be taxed. I suggest about four or five of those really big black garbage bags..
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