Section 9 Watertight doors
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Ships, July 2022 - Part 3 Ship Structures (General) - Chapter 11 Closing Arrangements for Shell, Deck and Bulkheads - Section 9 Watertight doors

Section 9 Watertight doors

Parent topic: Chapter 11 Closing Arrangements for Shell, Deck and Bulkheads

9.1 Openings in bulkheads

9.1.1 Certain openings below the freeboard deck are permitted, but these must be kept to a minimum and provided with means of closing to watertight standards. All such openings are to be to the satisfaction of the Surveyor.

9.2 Watertight doors below the freeboard/bulkhead deck

9.2.1 Watertight doors are to be of equivalent strength to the unpierced bulkhead, efficiently constructed and fitted, and are to be of an approved design.

9.2.2 The scantlings of the watertight doors are to comply with Pt 4, Ch 1, 9 Bulkheads using the actual stiffener spacing of the door.

9.2.3 The scantlings of the frames of the watertight doors are to satisfy the requirements of watertight bulkheads given in item 5 of Table 1.9.1 Watertight and deep tank bulkhead scantlings taking into account the arrangement of door stiffeners and securing arrangements.

9.2.4 Watertight doors are to be fitted in accordance with all requirements relating to their mode of operation, location, provision of controls, means of indication, etc. as given in Table 11.9.1 Watertight doors located below the freeboard/bulkhead deck.

9.2.5 All watertight doors, except those which are to be permanently closed at sea, are to be capable of being opened and closed locally from both sides of the door with the ship listed to either side.

9.2.6 For passenger ships, the angle of list at which the door is to be capable of being operated is 15 degrees.

9.2.7 For cargo ships, the angle of list at which the door is to be capable of being operated is 30 degrees.

9.2.8 Where indicated in Table 11.9.1 Watertight doors located below the freeboard/bulkhead deck, watertight doors are to be capable of being remotely closed by power from the bridge. For passenger ships, watertight doors are also to be capable of being remotely closed by hand from a position above the bulkhead deck.

9.2.9 For tankers, where there is a permanent access from a pipe tunnel to the main pump room, the watertight door shall be capable of being manually closed from outside the main pump room entrance in addition to the requirements given in Pt 3, Ch 11, 9.2 Watertight doors below the freeboard/bulkhead deck 9.2.8.

9.2.10 Where indicated in Table 11.9.1 Watertight doors located below the freeboard/bulkhead deck, means are to be provided on the navigating bridge to indicate whether the watertight doors are open or closed. Doors which are normally closed at sea but not provided with means of remote closure are to have notices fixed to both sides of the doors stating, 'To be kept closed at sea'. Doors which are to be permanently closed at sea are to have notices fixed to both sides stating, ‘Not to be opened at sea’.

9.2.11 All watertight doors are to be provided with an audible or visual alarm in accordance with the requirements of SOLAS - International Convention for the Safety of Life at Sea and applicable amendments, where indicated in Table 11.9.1 Watertight doors located below the freeboard/bulkhead deck.

9.2.12 Hinged watertight doors of approved pattern may be fitted in 'tween decks in approved positions. The hinges of these doors are to be fitted with gunmetal pins or gunmetal bushes.

9.2.13 The frames of vertical watertight doors shall have no groove at the bottom in which dirt might lodge and prevent the door closing properly.

9.2.14 Watertight doors are to be tested in accordance with the requirements of Pt 3, Ch 1, 9 Procedures for testing tanks and tight boundaries. The capability of the door to be opened/closed at the required angle of inclination is also to be confirmed, see Pt 3, Ch 11, 9.2 Watertight doors below the freeboard/bulkhead deck 9.2.6 and Pt 3, Ch 11, 9.2 Watertight doors below the freeboard/bulkhead deck 9.2.7.

9.2.15 For large doors intended for use in the watertight subdivision boundaries of cargo spaces, structural analysis can be accepted in lieu of structural testing. Where such doors utilise gasket seals, a prototype pressure test to confirm that the compression of the gasket material is capable of accommodating any deflection revealed by the structural analysis is to be carried out.

9.2.16 The following leakage criteria is to be complied with:

  • Doors with gaskets – no leakage;
  • Doors with metallic sealing – max leakage 1 l/min.
9.2.17 Limited leakage can be accepted for structural tests on large doors located in cargo spaces employing gasket seals or guillotine doors located in conveyor tunnels as follows:
where
P = perimeter of door opening in metres
h = test head of water in metres

Where h ≤ 6,10 metres, the leakage rate need not be taken greater than 0,375 l/min.

9.2.18 For doors on passenger ships which are normally open and used at sea or which become submerged at the equilibrium or intermediate waterline, see Pt 3, Ch 1, 6.10 Damage waterlines, a prototype test is to be conducted, on each side of the door, to check the satisfactory closing of the door against a force equivalent to water height of at least 1 metre above the sill on the centreline of the door.

Table 11.9.1 Watertight doors located below the freeboard/bulkhead deck

Usage at sea Type Remote closure Remote indication Alarm Notice Comments
Doors in internal watertight bulkheads
Passenger ships
Normally closed Power operated, sliding Yes Yes Yes (local) No Certain doors can be left open, see SOLAS II-1/22.2 and IMO MSC.1/Circular.1564 – Revised Guidance for Watertight Doors on Passenger Ships Which may be Opened During Navigation – (16 July 2017)
Permanently closed Sliding, hinged No No No Yes See Notes 2 and 3
Cargo ships
Used Power operated, sliding Yes Yes Yes (local) No
Normally closed Sliding, hinged No Yes No Yes See Note 1
Permanently closed Sliding, hinged No No No Yes See Note 2
Doors in external watertight boundaries below equilibrium or intermediate waterline
Passenger ships
Permanently closed Sliding, hinged No No No Yes See Note 3
Cargo ships
Permanently closed Sliding, hinged No Yes No Yes See Note 3
Notes
Note 1. If hinged, this door is to be of a quick acting or single action type.
Note 2. Doors are to be fitted with a device which prevents unauthorised opening.
Note 3. Passenger ships which have to comply with SOLAS II-1/14.2 require an indicator on the navigation bridge to show automatically when each door is closed, and all door fastenings are secured.
Note 4. Normally closed means doors are kept closed at sea but can be used if authorised and are to be closed again after use.
Note 5. Used means that the door is in regular use and can be kept open provided that it is ready to be immediately closed.

9.3 Watertight doors at or above the freeboard/bulkhead deck

9.3.1 Watertight doors located above the freeboard/bulkhead deck are to be in accordance with Pt 3, Ch 11, 9.2 Watertight doors below the freeboard/bulkhead deck except as amended by this Section.

9.3.2 Watertight doors are to be fitted in accordance with all requirements relating to their mode of operation, location, provision of controls, means of indication, etc. as given in Table 11.9.2 Watertight doors located at or above the freeboard/bulkhead deck.

9.3.3 For passenger ships, where it is required for a door to be watertight in order to meet damage stability requirements and such doors are located above the worst final and worst intermediate waterline, but where the door is fully or partly below the intermittent waterline, see Pt 3, Ch 1, 6.10 Damage waterlines such doors are to be power operated and remotely controlled sliding semi-watertight doors complying with the requirements of Pt 3, Ch 11, 9.2 Watertight doors below the freeboard/bulkhead deck except that the scantlings and sealing requirements are to be based on the maximum head of water corresponding to the intermittent waterline, see Pt 3, Ch 3, 5.5 Flooded loads.

Table 11.9.2 Watertight doors located at or above the freeboard/bulkhead deck

Usage at sea Type Remote closure Remote indication Alarm Notice Comments
Doors in internal watertight bulkheads
Passenger ships
Normally closed

Power operated, sliding

Power operated, hinged

 Yes Yes Yes (local) No See Note 5
Sliding, hinged No Yes No Yes See Note 1
Sliding, hinged No Yes Yes (remote) Yes Doors giving access to below Ro-Ro deck
Permanently closed Sliding, hinged No Yes Yes (remote) Yes See Notes 1 and 3
Cargo ships
Used Power operated, sliding Yes Yes Yes (local) No See Notes 3 and 4
Normally closed Sliding, hinged No Yes No Yes See Note 1
Permanently closed Sliding, hinged No No No Yes See Note 2
Doors in external watertight boundaries below equilibrium or intermediate waterline
Passenger ships
Normally closed Sliding hinged No Yes No Yes See Note 1
Sliding, hinged No Yes Yes (remote) Yes Doors giving access to below Ro-Ro deck
Permanently closed Sliding, hinged No No No Yes See Note 2
Cargo ships
Normally closed Sliding, hinged No Yes No Yes See Note 1
Permanently closed Sliding, hinged No Yes No Yes See Note 2
Notes
Note 1. If hinged, this door is to be of a quick acting or single action type.
Note 2. Doors are to be fitted with a device which prevents unauthorised opening.
Note 3.Under ICLL 66, doors separating a main machinery space from a steering gear compartment can be a hinged quick acting type provided that the lower sill of such doors is above the summer load line and the doors remain closed at sea whilst not in use.
Note 4. Under MARPOL, hinged watertight doors can be accepted in watertight bulkheads in superstructure.
Note Note 5. For sliding semi-watertight doors, see Pt 3, Ch 11, 9.3 Watertight doors at or above the freeboard/bulkhead deck 9.3.3.
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