(a) A door, other than a watertight door, must meet the requirements of this section.(b) A door in a fire control boundary must meet the following requirements:(1) A door in an accommodation space, stairway, stairtower, or corridor must be oriented vertically;(2) A door must be capable of operation from either side by one person;(3) With the exception of staterooms, a door in an accommodation space, stairway, stairtower, passageway, or control space must open in the direction of escape, where practicable;(4) Combustible veneers may be used on doors subject to the same restrictions as the fire control boundary in which the doors are fitted;(5) Door frames must be of rigid construction and provide at least a 12.7 millimeter (0.5 inch) overlap at the sides and top, except:(i) Double doors capable of independent operation and latching may have a clearance between the doors of not more than 3.2 millimeters (0.125 inches). However, if one door must always be closed first, means shall be provided to ensure that the doors close in the proper order; and(ii) A double swing door, may have a clearance of not more than 3.2 millimeters (0.125 inches) at the top and sides;(6) The maximum width of an individual door must not exceed 1200 millimeters (48 inches); and(7) Hose ports, if fitted, must be in the lower corner of the door opposite the hinge so a hose may pass through the doorway when the door is open and still allow the door to close over the hose. The hose port should be approximately 152 millimeters (6 inches) square. A self-closing hinged or pivoted steel or equivalent material cover must be fitted in the opening.(c) Doors in A-Class fire control boundaries must meet the following additional requirements:(1) A door in a bulkhead required to be A-60, A-30, or A-15 Class must be of hollow steel or equivalent material construction, solidly filled with approved structural insulation, and capable of meeting the requirements of an A-15 Class bulkhead;(2) A door in a bulkhead required to be A-0 Class must be of solid or hollow steel or equivalent material construction, and capable of meeting the requirements of an A-0 Class bulkhead;(3) A door must have a latch with a minimum throw of 20 millimeters (0.75 inches);(4) A door must not have vent grilles or louvers;(5) A door must not be undercut more than 12.7 millimeters (0.5 inches) above the door sill or deck covering. Rugs and carpets must not pass through doorways, but linoleum and similar deck coverings may;(6) A door in a stairtower, stairway, and main vertical zone bulkhead must meet the following additional requirements:(i) A door must be of the self-closing type capable of closing against a 3.5 list of the vessel; and(ii) Holdback hooks are not allowed. If installed, a hold back mechanism for a door must allow the door to be released:(B) Upon a signal from a control space; and(C) Upon disruption of the power system.(7) Horizontal doors (doors installed in decks) are allowed only for access to spaces that are accessible only to crew members and are used only by crew members, subject to the following requirements:(i) The door must be self-closing with a closure time of not less than 5 seconds and not more than 10 seconds, and be capable of closing against a 3.5 list of the vessel;(ii) Holdback hooks are not allowed. If installed, a holdback mechanism for a door must allow the door to be released:(B) Upon a signal from a control space; and(C) Upon disruption of the power system.(iii) The forces required to fully open the door must not exceed 17.8 Newtons (5 pounds) to release the latch, 44.5 Newtons (10 pounds) to set the door in motion, and 17.8 Newtons (5 pounds) to open the door to the width of the stairway; and(iv) The door latch must be capable of keeping the door closed when a pressure of 0.07 kPa (0.01 psi) is applied to the underside of the door.(8) Double swing doors must not be used in any bulkhead except between a food preparation space, such as a galley or pantry, and a messroom or dining room; and(9) A door opening onto weather decks must meet the requirements of paragraphs (c)(1) or (c)(2) of this section or may be composed of hardwood of not less than 45 millimeters (1.75 inches) in thickness. In any case, no restriction as to the area of glass will be made for the doors insofar as this subpart is concerned. Only glass of the wire-inserted type may be fitted in the doors.(10) Except as noted in paragraph (c)(9) of this section, doors may be fitted with not more than 0.065 square meters (100 square inches) of glass, which must be of the wire-inserted type.(d) Doors in B-Class fire control boundaries must meet the following requirements in addition to those in paragraph (b) of this section:(1) A door must be of solid or hollow steel or equivalent material construction, or must be of noncombustible material and be specifically approved by the Commandant;(2) A door must have a latch with a minimum throw of 9.5 millimeters (0.375 inches); and(3) A door must not be undercut more than 25 millimeters (1 inch) above the door sill or deck covering. Rugs and carpets must not pass through doorways but linoleum and similar coverings may.(e) A door in a C-Class bulkhead must be of noncombustible material.(f) A door used for decorative purposes, and that is not required to comply with paragraphs (b) through (e) of this section, must be constructed of noncombustible material or hardwood, must not interfere with the normal operation of the required doors, and must open in the same direction as the required doors. Decorative doors must not be used in stairways or stairtowers.CGD 85-080, 61 FR 900, Jan. 10, 1996, as amended at 62 FR 51350, Sept. 30, 1997