Fire Doors? Whats the big deal?

Why are the doors that the code requires so important? Does it really matter if the door is operational (closes fully, self-closing, etc.)?

The National Fire Protection Association has designated the following minimum fire protection ratings for walls and openings:

8.3 Fire Barriers.

8.3.1 General. Fire barriers used to provide enclosure, subdivision, or protection under this Code shall be classified in accordance with one of the following fire resistance ratings:

(1) 3-hour fire resistance rating

(2) 2-hour fire resistance rating

(3) 1-hour fire resistance rating

(4)* 1/2-hour fire resistance rating

8.3.3 Fire Doors and Windows. Openings required to have a fire protection rating by Table shall be protected by approved, listed, labeled fire door assemblies and fire window assemblies and their accompanying hardware, including all frames, closing devices, anchorage, and sills in accordance with the requirements of NFPA 80, Standard for Fire Doors and Other Opening Protectives. Unless otherwise specified, fire doors shall be self-closing or automatic-closing.

Here is the life saving benefits of a properly installed, working, fire door: