What the Examiner Is Testing
This topic catches candidates who conflate watertight and weathertight, confuse the operational status of different door types, or cannot explain what testing and maintenance actually consists of in service. The Master carries personal responsibility for these fittings — not the engineer, not the Chief Officer.
Watertight Doors
Types and location matter:
- Hydraulically or mechanically operated sliding watertight doors in watertight bulkheads are the primary concern. They must be operable from both sides locally AND from a remote position above the bulkhead deck.
- Hinged or quick-acting watertight doors are generally permitted only where a sliding door is impracticable; they must be kept closed at sea unless in active use, and must be capable of being closed in ≤30 seconds from the open position.
Operational regime (command-level responsibility):
- The Master decides which watertight doors may be held open during sea passage and must ensure this is recorded and justified — typically doors required for operational access, closed immediately on any flooding alarm.
- All watertight doors must be capable of being closed with the vessel listed.
- Indicators on the navigation bridge must show open/closed status for all remotely operated doors.
Testing and maintenance:
- Watertight doors and their mechanisms must be tested weekly during a voyage (this is the operational test — open and close under power and locally).
- Seals, drainage channels, and operating gear must be inspected as part of the SMS maintenance schedule.
- Records of tests are kept in the Official Log Book or SMS.
Side Scuttles (Portlights)
Distinction: Side scuttles below the margin line or in positions defined by the Load Line Rules must be fitted with deadlights (internal storm covers). Those in lower positions may be non-opening (fixed lights) or opening with a positive means of closure.
Operational rule: Opening side scuttles below a defined height above the waterline must be kept closed and secured at sea. The Master must issue standing orders to this effect and verify compliance before departure.
Maintenance: Hinges, fasteners, rubber seals, and deadlight mechanisms must be maintained operational. A corroded or seized deadlight that cannot be closed is a deficiency reportable to the flag state.
Scuppers
Distinction: Scuppers are deck drainage fittings — not hull openings for access, but potential flooding paths when the vessel is heeled or in heavy weather.
- Scuppers in enclosed spaces or leading from spaces below the freeboard deck must be fitted with non-return valves or equivalent positive means of closure.
- Open deck scuppers that are simply freeboard-deck drains may not require valves, but the Master must understand which scuppers have valves and verify they function.
- At sea in heavy weather, scupper valves should be closed to prevent ingress; this must be in standing orders.
Maintenance: Non-return valve flaps must be free-moving and seating correctly — a common survey deficiency. Operationally test by manual closure and inspection of seating.
The Command Angle
An examiner expects the Master to own this: know where every watertight door is, its operational status regime, who is responsible for closing it, and how you confirm it is closed before departure and in an emergency. The same ownership applies to side scuttles and scupper valves — these are not maintenance-only items; they are part of the vessel's damage-stability baseline.