The door in a 2-hour fire-barrier is required to have a rating of:

A door that is part of a 2-hour fire barrier must be rated to ensure it can effectively contribute to the overall fire resistance of the barrier. The purpose of fire-rated doors is to help prevent the spread of fire and smoke between compartments, providing enough time for occupants to escape and for firefighters to control the situation.

For a door in a 2-hour fire barrier, the appropriate rating for the door is typically set at 1 1/2 hour (or 90 minutes). This is because, according to fire safety codes, fire doors should have ratings that are at least equal to or less than the rating of the wall or barrier they are installed in. Therefore, while the wall is constructed for a 2-hour rating, the door is permitted to be rated at 1 1/2 hours to maintain effectiveness without necessitating it to match the full duration of the wall.

This rating ensures that the door can withstand fire conditions long enough to provide protection, acknowledging that the wall may contain fire longer but still allowing for some compromise in the door's structural integrity for practical reasons, such as availability and functionality. Consequently, needing a door to achieve a full 2-hour rating, as incorrectly indicated by one of the distractions in