Regulation 23 - Side scuttles, windows and skylights
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Conventions - Load Lines, 1966/1988 - International Convention on Load Lines, 1966, as Amended by the Protocol of 1988 - Annex I - Regulations for Determining Load Lines - Chapter II - Conditions of Assignment of Freeboard - Regulation 23 - Side scuttles, windows and skylights

Regulation 23 - Side scuttles, windows and skylights

  (1) Side scuttles and windows, together with their glasses, deadlights and storm coversfootnote, if fitted, shall be of an approved design and substantial construction. Non-metallic frames are not acceptable.

  (2) Side scuttles are defined as being round or oval openings with an area not exceeding 0.16 m2. Round or oval openings having areas exceeding 0.16 m2 shall be treated as windows.

  (3) Windows are defined as being rectangular openings generally, having a radius at each corner relative to the window size and round or oval openings with an area exceeding 0.16 m2.

  (4) Side scuttles to the following spaces shall be fitted with hinged inside deadlights:

  • (a) spaces below freeboard deck;

  • (b) spaces within the first tier of enclosed superstructures; and

  • (c) first tier deckhouses on the freeboard deck protecting openings leading below or considered buoyant in stability calculations.

 Deadlights shall be capable of being closed and secured watertight if fitted below the freeboard deck and weathertight if fitted above.

  (5) Side scuttles shall not be fitted in such a position that their sills are below a line drawn parallel to the freeboard deck at side and having its lowest point 2.5% of the breadth (B), or 500 mm, whichever is the greatest distance, above the Summer Load Line (or Timber Summer Load Line if assigned).

  (6) If the required damage stability calculations indicate that the side scuttles would become immersed at any intermediate stage of flooding or the final equilibrium waterline, they shall be of the non-opening type.

  (7) Windows shall not be fitted in the following locations:

  • (a) below the freeboard deck;

  • (b) in the first tier end bulkheads or sides of enclosed superstructures; or

  • (c) in first tier deckhouses that are considered buoyant in the stability calculations.

  (8) Side scuttles and windows at the side shell in the second tier shall be provided with hinged inside deadlights capable of being closed and secured weathertight if the superstructure protects direct access to an opening leading below or is considered buoyant in the stability calculations.

  (9) Side scuttles and windows in side bulkheads set inboard from the side shell in the second tier which protect direct access below to spaces listed in paragraph (4) shall be provided with either hinged inside deadlights or, where they are accessible, permanently attached external storm covers which are capable of being closed and secured weathertight.

  (10) Cabin bulkheads and doors in the second tier and above separating side scuttles and windows from a direct access leading below or the second tier considered buoyant in the stability calculations may be accepted in place of deadlights or storm covers fitted to the side scuttles and windows.

  (11) Deckhouses situated on a raised quarter deck or on the deck of a superstructure of less than standard height may be regarded as being in the second tier as far as the requirements for deadlights are concerned, provided that the height of the raised quarter deck or superstructure is equal to or greater than the standard quarter deck height.

  (12) Fixed or opening skylights shall have a glass thickness appropriate to their size and position as required for side scuttles and windows. Skylight glasses in any position shall be protected from mechanical damage and, where fitted in position 1 or 2, shall be provided with permanently attached deadlights or storm covers.


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