said by LazMan:
As for remote car starters, also by code, the garage must be sealed from the occupied portion of the house, and the seal must be gas proof, including caulking around all penetrations; the door must have a gasket, and an automatic closer...
In-law's place in Montreal has an attached garage. The door to the garage does not have an automatic closer. The living spaces above (8 units, I think) do not have carbon monoxide detectors.
I don't think people are stupid enough to run a car in a closed garage, but the cars can be started accidentally. Suppose a 3 year-old starts playing with the buttons on a keyfob.
I never heard of a requirement that residential gas ranges/ovens have an exhaust vent.