Means of Egress and Exit Requirements
The Egress System
The means of egress has three parts: exit access (the path from the occupied space to the exit), the exit (the protected way out, such as an enclosed stair or exit door), and exit discharge (the path from the exit to the public way). Candidates must understand capacity, number of exits, travel distance, common path, dead ends, and the dimensions of egress components.
Capacity and Number of Exits
Egress capacity is calculated from occupant load multiplied by a capacity factor that depends on the egress component (stairs, corridors, doors). The number of exits depends on occupant load and occupancy group. Traps include forgetting that the occupant load must be calculated from the use and floor area before capacity, or assuming a single exit is acceptable in a large space. Another trap: confusing travel distance (to the exit) with common path (the distance before two separate paths exist).
Worked Example / Rule of Thumb
Rule of thumb: calculate in this order - (1) occupant load from area and use factor, (2) required egress width from load × capacity factor, (3) number of exits from load and occupancy. If a stem gives a floor area and a use, the first move is always to compute occupant load; many distractors are built on a wrong occupant load.
Exam Strategy
Check the units and the order of operations. Most egress errors come from skipping the occupant-load step or mixing travel distance with common path.