Paging all chemistry experts: how can I tell if it's N2 or Air?

[Will Collier]

space-time wrote:
I could force one of my less friendly co-workers breathe this stuff and see if they pass out. But I am looking into some non arson, non violent methods.

any ideas?

Thanks

Spoilsport. I was going to suggest, "Breathe it and see if you turn blue."