Means of Egress and Interior Finish Requirements
The egress chain
Means of egress is the most heavily tested domain. It has three parts: exit access (path to the exit), exit (the protected way out, e.g., enclosed stair), and exit discharge (path to public way). Every egress question can be solved by asking which component is at issue. Key concepts: number of exits (two required for most occupancies above a threshold occupant load), travel distance, common path, dead-end corridors, exit width (based on occupant load and inches per occupant), and door swing (swinging in the direction of egress travel for high-occupancy rooms).
Interior finish
Interior finish is classified by flame-spread and smoke-developed index, with stricter limits in exits and corridors. The trap: people forget that finish limits tighten as you move into the exit access and exit.
Worked rule of thumb
For a door question, check three things: does it swing in the direction of travel (required for rooms with high occupant load), is it side-hinged, and does it have the required clear width? For travel distance, compare the actual path to the code's maximum for the occupancy - if exceeded, a second exit or sprinkler trade-off may be required.
Traps
Don't count an exit as valid if it passes through a room that can be locked. Don't confuse travel distance (to the exit) with common path (shared route before paths diverge). And remember: an exit access corridor blocked by storage is a violation even if the exit itself is perfect.