Cities and towns; buildings; single-stairway apartment; effective date.

HB 3913 allows Oklahoma municipalities to permit apartment buildings with a single stairway, provided they meet strict fire safety requirements. It directly affects apartment developers and city building departments by setting conditions like maximum height (six stories), unit limits (four per floor), fire-resistant stair enclosures (two-hour rating), automatic sprinklers, and specific exit pathways. Key provisions require sprinklers in all stairways, doors that swing correctly for exits, corridors with one-hour fire protection, and smoke detection systems in common areas. The bill takes effect November 1, 2026, and does not override existing building codes but gives cities authority to adopt this exception.