How does this prerequisite apply to a dormitory that has exterior motel-style walkways (no indoor conditioned corridors between rooms) where the residents are allowed to smoke in the individual units? Do these doors still need to be weather-stripped if they lead to the outdoors?

Also, if the individual living units are pre-fabricated off-site and "stacked" to form the building, does this suffice for minimizing ETS transfer?

What is considered a penetration in the walls, ceiling, and floors?