It's very much a selective thing. Humans vs meat machines.
I'm a meat machine. The factory I work in regularly gets over 90°F in the summer and being on long Island its also humid as fuck like 75%+.
I checked the NY state laws on factory conditions and wouldn't you know it, the fucking laws are vague as shit to allow essentially anything... "All factories must maintain a reasonable temperature and humidity." That's the fucking law. "Reasonable" is not defined anywhere in that law... I contacted my business cuck "R"epresentative about what that law means or how we determine what is reasonable, and yet again wouldn't you know, he never responded...
Been there done that too when I was a toolmaker. Old buildings with no air flow, (except in the winter on sub-zero F days). But hey, sometimes on the really bad days we would get an extra 5 minutes at break. And maybe on very rare occasions, a Popsicle.
For ambulances, if the air conditioning is broken in the patient compartment it's considered a critical fault and the vehicle needs to be out of service. In the cab it's a minor. Maybe it's in case a judge needs to be transported.