Your examiner asks: "What would you consider before opening a Type D watertight door while on passage?"

A. Confirm there is an operational and safety justification for opening it (e.g. essential access, with no safe alternative route), that it will be reclosed immediately after the necessary passage, that the bridge/responsible officer is aware and the door's open status is indicated/monitored throughout, and that sea conditions and the vessel's loaded/damage condition do not make the brief opening an unacceptable risk — door types intended to remain closed at sea are not opened routinely or for convenience.

B. Type D doors may be left open indefinitely at sea provided a crew member is nominated to "keep an eye on it" rather than reclosing it immediately.

C. No assessment is required — any watertight door may be opened at any time at the discretion of any crew member without reference to the bridge.

D. Watertight door type has no bearing on whether it is safe to open at sea; the only relevant factor is current sea state.

A. SOLAS classifies watertight doors by type based on how/when they may be operated: broadly, hinged doors normally kept closed at sea, sliding doors that may be power-operated and remotely controlled from the bridge, and doors with progressively stricter operating restrictions the closer they are to the waterline/the more safety-critical the bulkhead — the key distinction tested is which types may be open while the vessel is at sea versus which must remain closed underway except for brief, authorised passage with immediate reclosure.

B. All watertight doors on a RoRo vessel are functionally identical; there is no SOLAS distinction in type or permitted operating mode.

C. Watertight door types relate only to fire rating (A-class/B-class), not to watertight integrity or permitted operating mode at sea.

D. Door type only matters for new-build vessels; vessels built before 2009 have no door-type distinctions to know.