426.1.2 Grinding rooms.
BC § 426.1.2
Every room or space occupied for grinding or other operations that produce combustible dusts in such a manner that the room or space is classified as a Group H-2 occupancy shall be enclosed with fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both. The fire-resistance rating of the enclosure shall be not less than 2 hours where the area is not more than 3,000 square feet (279 m 2 ), and not less than 4 hours where the area is greater than 3,000 square feet (279 m 2 ).
