46 C.F.R. § 108.133 Hull superstructure, structural bulkheads, decks, and deckhouses.
Title 46 - Shipping
Each hull superstructure, structural bulkhead, deck, and deckhouse must be made of steel or an equivalent material.
Title 46: Shipping
PART 108—DESIGN AND EQUIPMENT
Subpart B—Construction and Arrangement
Structural Fire Protection
§ 108.133 Hull superstructure, structural bulkheads, decks, and deckhouses.