Commercial plumbing how many fixtures to air vent can there be and is there a chart somewhere on the web I can use?

Not an easy answer here bjsmico...

Each area/state has it's own codes and each code differs in terms of distance requirements, size of vents and whether you need to individually vent each fixture or you can combine vents to make wet vents.

I would refer you to your local library and see if they have an up to date plumbing code book...

Otherwise, find out what code prevails in your area by calling the local plumbing inspector and then pop back with that information and more about what you are trying to accomplish, specifically.

We need number of fixtures, distances, and some idea of basic layout of things... see what we can come up with once we know what this is for.

Back to you...

MARK