Sidescuttles, windows and skylights ( Regulation 23 ) (IACS interpretation LL.62)
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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 - Unified Interpretations of the Provisions of the International Convention on Load Lines, 1966 - Sidescuttles, windows and skylights (Regulation 23) (IACS interpretation LL.62)

Sidescuttles, windows and skylights ( Regulation 23 ) (IACS interpretation LL.62)

 Sidescuttles and windows together with their glasses, deadlightsfootnote and storm coversfootnote, if fitted, should be of approved design and substantial construction in accordance with, or equivalent to, recognized national or international standards. Non-metallic frames should not be acceptable.

 Sidescuttles 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 should be treated as windows.

 Windows are defined as being rectangular openings generally, having a radius at each corner relative to the window size in accordance with recognized national or international standards, and round or oval openings with an area exceeding 0.16 m2.

 Sidescuttles to the following spaces should be fitted with efficient hinged inside deadlights:

  • .1 spaces below freeboard deck;

  • .2 spaces within the first tier of enclosed superstructures; and

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

The deadlights should be capable of being effectively closed and secured watertight, if fitted below freeboard deck, and weathertight, if fitted above.

 Sidescuttles should 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).

 Sidescuttles should be of the non-opening type in ships subject to damage stability regulations, if calculations indicate that they would become immersed by any intermediate stage of flooding or the final equilibrium waterplane in any required damage case.

 Windows should not be fitted below the freeboard deck, in the first tier end bulkheads or sides of enclosed superstructures and in first tier deckhouses considered buoyant in the stability calculations or protecting openings leading below.

 Sidescuttles and windows at the side shell in the second tier, protecting direct access below or considered buoyant in the stability calculations, should be provided with efficient hinged inside deadlights capable of being effectively closed and secured weathertight.

 Sidescuttles and windows set inboard from the side shell in the second tier, protecting direct access below to spaces listed in paragraph 3.4 above, should be provided with either efficient hinged inside deadlights or, where they are accessible, permanently attached external storm covers of approved design and of substantial construction and capable of being effectively closed and secured weathertight.

 Cabin bulkheads and doors in the second tier separating sidescuttles and windows from a direct access leading below may be accepted in place of deadlights or storm covers fitted to the sidescuttles and windows.

 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 provision of deadlights is concerned, provided the height of the raised quarter-deck or superstructure is equal to, or greater than, the standard quarter-deck height.

 Fixed or opening skylights should have glass thickness appropriate to their size and position as required for sidescuttles and windows. Skylights glasses in any position should be protected from mechanical damage and, where fitted in position 1 or 2, should be provided with robust deadlights or storm covers permanently attached.


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