Hatch

A hatch is an opening in a ship’s deck giving access to a cargo hold, store, or compartment, closed by a hatch cover that must be weathertight under the International Convention on Load Lines 1966, Regulations 13 to 16. The coaming is the raised frame around the opening; on Position 1 weather decks the coaming height is generally 600 mm. Modern bulk carriers use steel folding or side-rolling covers tested by hose or ultrasonic methods. The hatchway is the opening itself; loss of cover weathertightness is a major down-flooding and cargo-damage risk.