2.3 “A” Class Doors
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Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.754(18) – Recommendation on Fire Resistance Tests for “A”, “B” and “F” Class Divisions – (Adopted on 4 November 1993) - Annex - Recommendation on Fire Resistance Tests for “A”, “B” and “F” Class Divisions1 - 2 Nature of Test Specimens - 2.3 “A” Class Doors

2.3 “A” Class Doors

Parent topic: 2 Nature of Test Specimens

2.3.1 Dimensions

 The test specimen should incorporate the maximum size (in terms of both the width and the height) of door leaf or leaves for which approval is to be sought. The maximum size of a door which can be tested will be determined by the requirement to retain certain dimensions of the structural core (see 2.3.2.2).

2.3.2 Design

  2.3.2.1 The door leaf and frame should be constructed of steel or other equivalent material and insulated as necessary to achieve the desired standard of insulation.

 Door furniture such as hinges, locks, latches, shoot bolts, handles, etc. should be constructed of materials having melting points of not less than 950°C.

  2.3.2.2 The door leaf and frame should be mounted into a structural core constructed in accordance with 2.1.1.

 An opening to accommodate the door assembly should be provided in the structural core; the maximum dimensions of the opening will be determined by a requirement to retain a minimum width of the structural core of 300 mm to each vertical side of the opening and a minimum distance of 100 mm from the top edge of the structural core.

 No additional stiffening should be provided to the structural core unless provided as part of the door frame.

 The method of fixing the door frame into the opening in the structural core should be as used in practice.

  2.3.2.3 The structural core should be mounted such that the stiffeners are on that side which is intended to face away from the heating conditions of the test (i.e. the unexposed face), whilst the insulating system should be on the side intended to be exposed to the heating conditions of the test (i.e. the exposed face).

  2.3.2.4 The insulation system should be approved by the Administration to at least the same standard as that which the door is intended to achieve. If the insulation performance of the door is unknown the structural core should be insulated to A-60 standard. The insulation of the structural core should not be extended beyond the outer web of the door frame.

  2.3.2.5 The door should be mounted into the structural core such that the side expected to give the inferior performance will be exposed to the heating conditions of the test.

 A hinged door should be tested with the door leaf opening away from the heating conditions unless the Administration deems otherwise.

 For sliding doors it is not possible to state generally from which side the door should be tested to give the inferior performance. It will, therefore, be necessary to conduct two separate tests, one with the door mounted to the exposed face and one with the door mounted to the unexposed face of the bulkhead. If, for practical reasons, a sliding door cannot be fixed to the stiffened face of the structural core, then, subject to the agreement of the Administration, the stiffeners may be positioned on the exposed face.

2.3.3 Description

 The applicant should provide full constructional details of the test specimen in the form of drawings (including a detailed schedule of components) and method of assembly, such that the laboratory is able to confirm agreement between the actual specimen and the drawings and specifications prior to the test. The drawings should include dimensions and details of the following:

  • the bulkhead;
  • the door leaf and frame construction, including the clearances between the door leaf and the frame;
  • the connection of the door frame to the bulkhead;
  • the method of securing insulation and details of components used for this purpose (e.g. the type and rate of application of any adhesive);
  • fittings such as hinges, shoot bolts, latches, locks, etc.
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