2.5 Doors and Openings above the Weather Deck:

(1) All access openings in bulkheads at ends of enclosed superstructures shall be fitted with weathertight doors of steel or other equivalent material, permanently and strongly attached to the bulkhead, and framed, stiffened and fitted so that the whole structure is of equivalent strength to the un-pierced bulkhead; the means for securing these doors weathertight shall consist of gaskets and clamping devices or other equivalent means which shall be permanently attached to the bulkhead or to the doors themselves, and the doors shall be so arranged that they can be operated from both sides of the bulkhead.

(2) Unless otherwise permitted by the Administration, doors shall be hinged at the forward edge and open outwards to provide additional security against the impact of the sea; alternative closing arrangements will be considered providing it can be demonstrated that the efficiency of the closing arrangements and their ability to prevent the ingress of water will not impair the safety of the vessel.

(3) Except as otherwise provided in this Chapter, the height of sills of access openings in bulkheads at ends of enclosed superstructures shall be at least 380 millimetres above the deck.

(4) Portable sills shall generally be avoided provided that where the fitting of a sill in accordance with subsection (3) proves impracticable, portable sills may be fitted on the following conditions-

• (a) they shall be installed before the ship leaves port; and

• (b) they shall be gasketed and fastened by closely spaced through bolts or other equivalent arrangement.

(5) Where the requirements of section 2.2(2) are applicable further reductions in sill heights may be permitted provided that the Administration is satisfied that the safety of the ship is not impaired in any sea conditions and the safety of the ship will be assumed not to be impaired if the vessel can comply with the enhanced survivability standard as defined in section 4.30 with the space to which the door leads flooded.

(6) For the purpose of this section, two positions of hatchways, doorways and ventilators are defined as follows-

• (a) Position 1:

  • (i) upon exposed freeboard and raised quarterdecks, and upon exposed superstructure decks situated forward of a point located a quarter of the ship’s length from the forward perpendicular; and

• (b) Position 2:

  • (i) upon exposed superstructure decks situated abaft a quarter of the ship’s length from the forward perpendicular and located at least one standard height of superstructure above the freeboard deck; or

  • (ii) upon exposed superstructure decks situated forward of a point located a quarter of the ship’s length from the forward perpendicular and located at least two standard heights of superstructure above the freeboard deck.

(7) Machinery space openings in Position 1 or 2 shall be properly framed and efficiently enclosed by steel or equivalent casings of ample strength and where machinery casings are not protected by other structures, their strength and protection arrangements shall be specially considered.

(8) Access openings in the casings referred to in subsection (7)-

• (a) shall be fitted with doors complying with the requirements of subsection (1), the sills of which shall be at least 600 millimetres above the deck if in Position 1, and at least 380millimetres above the deck if in Position 2;

• (b) other openings in such casings shall be fitted with equivalent covers, permanently attached in their proper positions; and

• (c) where the provision of fixed sills as required in this section proves impracticable, consideration may be given to the provision of portable sills, subject to the requirements of subsection (4).

(9) Coamings of any fiddley, funnel or machinery space ventilator in an exposed position on the freeboard deck or superstructure deck shall be as high above the deck as reasonable and practicable provided that, subject to section 2.5(10), ventilators necessary to continuously supply the machinery space shall have coamings of sufficient height to comply with section 2.9(5), without having to fit weathertight closing appliances.

(10) Where due to size of vessel or nature of the design compliance with the coaming heights required by subsection (9) for ventilators necessary to continuously supply the machinery space proves impracticable, reduced coaming heights may be accepted subject to the following-

• (a) the ventilators are-

  • (i) fitted with louvres and other such devices to prevent water ingress; and

  • (ii) provided with permanently attached closing appliances.

• (b) the ventilators and supply system is so designed to ensure that an adequate uninterrupted supply of ventilation can be maintained with the weather side closed off.

• (c) the vessel can comply with the enhanced survivability standard as specified in section 4(30), with the machinery space flooded.

(11) Fiddley openings shall be fitted with strong covers of steel or other equivalent material permanently attached in their proper positions and capable of being secured weathertight.