Means of Egress and Accessibility
The Egress Concept
Means of egress is a continuous path in three parts: exit access, the exit, and exit discharge. Every point must lead to a public way without passing through a higher-hazard area. Candidates must be able to calculate occupant load from floor area factors or fixed seating, apply the correct egress width factor per component, and verify travel distance and common path limits.
Components and Arrangement
Know requirements for number of exits based on occupant load, remoteness of exits, interior exit stairways and ramps, exit passageways, and horizontal exits. Door requirements are a rich source of questions: swing direction, clear width, hardware, panic hardware where required, and the treatment of revolving and power-operated doors.
Accessibility Integration
Accessible routes, accessible means of egress, areas of refuge, and accessible signage must be coordinated with the egress design. Understand when an area of refuge or an accessible route to an elevator lobby is required, and how two-way communication provisions apply.
Worked Example
A business floor of 20,000 sq ft has an occupant load factor of 100 sq ft per person, giving 200 occupants. With a sprinklered building and two exits, the egress width rule of thumb is to apply the width factor per occupant and per component, then confirm the clear width of each door and stair exceeds the calculated value. Also confirm the exits are remote enough from one another.
Traps to Watch
Questions frequently confuse gross versus net floor area, forget that occupant load can be increased by concentrated use, or assume a single exit is acceptable above the occupant threshold.