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IBC Section 1003 — General Occupancy Calculations

Updated Apr 3, 2026
Establishes methodology for determining occupant load and posting requirements.

Section 1003 requires occupant load calculations based on occupancy type and floor area. Signs must be posted at exits displaying maximum occupancy. Occupancy determination affects egress capacity, number of exits, and emergency equipment sizing. Building officials may adjust occupancy limits based on actual usage patterns or safety concerns. Changes in use trigger new occupancy calculations and potential code upgrades.

TAGS
ibcoccupancyload-calculations
DETAILS
section
1003
category
Occupancy
code body
IBC
code year
2021
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