Egress Capacity and an Accessible Ramp in a Community Hall
A 2,500-square-foot Group A-3 community hall is being renovated. The occupant load is calculated at 15 square feet per occupant, giving 167 occupants. The room has a 36-inch front door and a 32-inch rear door. The rear exit route runs through a 36-inch-wide corridor for 40 feet and then down a ramp with a slope of 1:10 and a 6-foot landing at the bottom. The owner wants to add 30 folding chairs along the side wall, bringing the occupant load to 197, and asks whether the existing exits and ramp can remain.
1. Calculate the required number of exits and the minimum egress width for 167 occupants, and evaluate the two doors and corridor.
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At 15 square feet per occupant, 2,500 square feet gives 167 occupants. For an A-3 occupancy at that occupant load, two exits are required.
Using the level-component egress capacity factor of 0.2 inch per occupant:
- Required width = 167 × 0.2 = 33.4 inches.
- The 36-inch corridor provides 36 inches, so it is adequate for 167 occupants.
- The 36-inch front door is adequate.
- The 32-inch rear door meets the minimum clear-width threshold for a door, but its capacity is only 32 ÷ 0.2 = 160 occupants. If the rear exit is assigned more than 160 occupants, it is undersized even though the total width of both exits exceeds 33.4 inches.
The doors and corridor are therefore close to the limit, and the distribution of occupants between the two exits must be checked.
2. Evaluate the ramp under accessibility and egress requirements.
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The 1:10 ramp is not compliant. An accessible route ramp may not be steeper than 1:12, and egress ramps are also limited to that slope. A 1:10 ramp is too steep for wheelchair users and for many ambulatory users with disabilities, and it would not satisfy the accessible-route requirements even if it is part of the egress path.
The ramp must be reconstructed at 1:12 or flatter, with compliant landings at the top and bottom, edge protection, and handrails where required. The 6-foot landing is also too short for a typical ramp landing; landings must be at least as long as the required width and must provide maneuvering space. The official should not approve the ramp as an accessible route or as a compliant egress component.
3. If the 30 chairs are added, does the egress comply?
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No. At 197 occupants, the required level-component width becomes 197 × 0.2 = 39.4 inches. The 36-inch corridor now provides less than the required width, so the rear route is undersized regardless of the door widths.
The doors also become marginal: the 36-inch door has a capacity of 180 occupants, and the 32-inch door has a capacity of 160. Their combined capacity exceeds 197, but the 36-inch corridor and the distribution between exits still govern. The owner must either:
- Widen the corridor to at least 40 inches and verify the doors and exit distribution, or
- Add or reconfigure exits so that the occupant load is served within the capacity of each exit and the common path limits.
The existing arrangement cannot remain unchanged with the added chairs.