Hilariously enough it can even vary within states. EG: AFAIK, only two counties in Washington state require emissions testing on a semi-regular basis, and nowhere requires safety inspections.

I got burned by this by moving to one of the two counties with an otherwise innocuous check engine light that would have failed the emissions test so I had to get it fixed.

The federal EPA requires states to run emissions inspections in urban counties but leaves it up to the state for rural counties.

There's no federal requirement for safety inspections so that varies state to state.

Good to know! I'll have to go look up what the threshold for an 'urban county' is now, thanks.

And as others have mentioned, even if the state does not, sometimes the county does which means inspection standard vary wildly.