46 CFR § 32.56-45
Draft stops—T/ALL
April 15, 2021
(a) Where ceilings or linings are fitted in accommodation, service, or control spaces, “B” Class bulkheads, except those that form passageways, may stop at the ceiling or lining if draft stops of “B” Class construction are fitted between the ceiling or lining and the deck or shell at intervals of 14 meters (45 feet) or less.
(b) Spaces behind the linings of stairways and other trunks must have draft stops at each deck.