[loungitude]

Here’s my understanding:
Nitrous oxide “nitrous” sold for automotive use has a tiny bit of ‘teargas’ or similar irritant in it. The idea is to keep people from getting high from inhaling it.
The food-grade stuff, and the medical stuff that the dentist administers, does not have the noxious additive.
I’d guess that the car guys have figured out how to remove the irritant. I would bet that a charcoal filter would do that.

[nascarnation]

Thanks for the info, did not know that.
Makes perfect sense.