StacksVerified U.S. regulatory reference

46 CFR §45.151

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
Each opening other than hatchways, machinery space openings, manholes, or flush scuttles—
  1. (a)In freeboard decks, must be protected by an enclosed superstructure or by a deckhouse or companionway that is equal in strength and weathertightness to an enclosed superstructure; or
  2. (b)In exposed superstructure decks or in the top of a deckhouse on freeboard decks that gives access to a space below the freeboard deck or a space within an enclosed superstructure, must be protected by a deckhouse or companionway.