|TIERED SEATING ELEMENT||LOAD TYPE||LOAD|
|Seats (vertical)||L||120 pounds per linear foot.|
|Treads||L||Stair treads and aisle stair treads shall be designed to resist a minimum concentrated load of 300|
pounds on an area of 4 square inches.
|Handrails and guards, |
|Rr||Handrail assemblies and guards shall be designed to resist a load of 50 pounds per linear foot|
(pound per foot) applied in any direction at the top. The supporting elements shall transfer this
load to the structure.
|Handrails and guards, |
|Rr||Handrail assemblies and guards shall be able to resist a single concentrated load of 200 pounds,|
applied in any direction at any direction along the top. Attachment devices and supporting elements
shall transfer this load to the structure.
|Guards, infill components||Rr||Intermediate rails (all those except the handrail), balusters, and panel fillers (including flexible|
infill components) shall be designed to withstand a horizontally applied normal load of 50 pounds
on an area equal to 1 square foot, including openings and space between rails. Application of the
loads shall not allow guard openings greater than that permitted by Sections 408.2 and 503.2.
|For SI: 1 square inch = 645.46 mm2, 1 square foot = 0.0929 m2, 1 pound = 4.448 N, 1 pound per linear foot = 14.594 N/m.|
|1.2D + 1.0L + 1.6Z||(Equation 3-1)|
|1.2D + 1.2Rr||(Equation 3-2)|
|D + 0.75L + 0.75Z||(Equation 3-3)|
|D + 0.75Rr||(Equation 3-4)|
|D||=||dead load as defined by the building code|
|L||=||live load as defined by Section 303.2|
|Z||=||horizontal sway loads as defined by Section 303.4.2 and Section 303.4.3|
|Rr||=||guard or handrail loads as defined in Table 303.2|
1. An emergency voice/alarm system is not required for outdoor bleacher-type seating provided all of the following are met:
1.1. The bleacher-type seating has an occupant load of less than 15,000.
1.2. A public address system with standby power is provided.
1.3. Enclosed spaces attached or immediately adjacent to the bleacher-type seating comprise, in the aggregate, 10% or less of the overall area of the bleacher-type seating or 1,000 square feet (92.9 square meters), whichever is less.
1.4. Spaces under the bleacher-type seating shall be separated from the bleacher-type seating in accordance with Section 1028.1.1.1 of the International Building Code.
1.5. All means of egress from the bleacher-type seating are open to the outside.
3. An emergency voice/alarm system is not required for temporary outdoor bleacher-type seating providing all of the following are met:
3.1. There are no enclosed spaces under or attached to the bleacher-type seating;
3.2. The bleacher-type seating is erected for a period of less than 180 days;
3.3. Evacuation of the bleacher-type seating is included in an approved fire safety plan.