Projection engineering (Jan-Dec 1931)

SEPTEMBER, 1931 Page 19 be used only in buildings not of fireresistive construction.) (b) Partitions shall be continuous from floor to ceiling and securely anchored to walls, floor and ceiling. (c) Openings in partitions shall be protected by approved fire doors of a type suitable for use in Class C situations as defined in the Regulations for the Protection of Openings in Walls and Partitions Against Fire. 113. Exits. It is essential that all rooms in which film is handled be provided with adequate aisle space and safe means of egress. Rooms in which film is handled and in which more than two persons work shall have two or more exits, remote from each other. Every exit shall be marked "Exit" in letters not less than 6 inches high, or by an illuminated sign with letters of the same height. 114. Vents. All new buildings erected to be used as, and all existing buildings remodelled for film occupancies shall be provided in every room where film is to be stored or handled, with vents which will open automatically in case of fire. These should be of ample size ; they may be in the form of automatic skylights or automatic-opening window sash. All rooms in which film is stored or handled in existing buildings shall be provided with such vents wherever practicable. 115. Spacing of workers. A feature which often contributes materially to the hazard to life in film handling rooms is the congestion of workers together with large quantities of film. To prevent such congestion of workers and the attendant hazard to life, the number of persons working in a room where film is handled should never be more than will result in a ratio of floor area to number of workers, less than 35 square feet per person. Not over 15 persons shall work at one time in any one room (not including the stage of motion picture studios) in which film is handled. 116. Tables arid racks. Tables and racks used in connection with the handling of film (joining, inspection and assembling tables for example) shall be of metal or other non-combustible material. They should be kept at least 4 inches away from any radiator or heating apparatus. Tables shall not be provided with racks or shelves underneath them, which might be used for keeping film or other materials. Section 12. Electrical Equipment 121. Artificial illumination in any room where film is handled or stored shall be restricted to incandescent electric lights, except that arc lights or other forms of electric lights may be used in studios. 122. All electrical wiring and equipment shall conform to the National Electric Code. Wiring shall be in metal conduit, and fuses shall be enclosed. 123. Light fixtures shall be firmlyfixed in place and lights shall be protected by vapor-proof globes. All lights shall be equipped with keyless sockets and operated by wall switches. 124. Light boxes reading "EXIT" in letters not less than six inches in height shall be placed at the exits of all dark rooms. 125. Portable electric lights on extension cords are prohibited in any room (not including the stage of motion picture studios) in which film is handled or stored. 126. Motors shall be of the nonsparking type, or shall be of an enclosed type, so arranged as to minimize the danger of sparks. 127. Motion picture projectors shall be of an approved type and safeguarded in accordance with the requirements of the National Electrical Code, Article 35. Section 13. Heating Equipment 131. Artificial heating in any building or room, other than a vault, in | I j* ROM the life standpoint a § I JT^ fire having only a small | | property loss may be as disas j I trous as one involving considera | | ble damage. A gruesome tragedy I 1 is all too likely to occur when a \ I fire breaks out in a theatre during | | a performance. Even a small fire, \ 1 with a crowded auditorium and j § panic, assumes tremendous pro I | portions. j which motion picture film is used, handled or stored, shall be restricted to steam not exceeding 10 pounds pressure or hot water, provided however, that this shall not be construed as prohibiting the installation of an indirect system employing high pressure steam when the radiators or heating coils of such system are not located in the room or rooms to be heated. Heat generating apparatus shall be in separate room. Note : Ordinary hot air furnaces are prohibited. Gas, oil and electric heaters are prohibited in rooms where film is handled or stored. 132. All steam pipes within 6 feet of the floor, and where passing through partitions or racks or near woodwork, shall be covered with approved pipe covering. All radiators, heating coils, and pipes and returns that are near the floor or are so located as to permit any combustible material, waste or dirt to come in contact therewith shall be guarded and perfected by means of j4-inch mesh galvanized steel wire cloth No. 20 B. & S. Gauge, or by its equivalent. The bottom of such guards shall be arranged so as to lift up for cleaning purposes and the tops to slope so that guards cannot be used as shelves. Guards shall be so constructed that no film can come within 4 inches of the heating surface, and shall be made with a substantial metal framework which will prevent the wire mesh being forced against the radiator or pipes. Section 14. Sprinklers and Other Fire Protection Appliances 141. Every room in which film is stored or handled in quantities greater than 50 pounds (10 standard rolls), except in motion picture projection booths or rooms and rewinding rooms connected therewith, shall be equipped with an approved system of automatic sprinklers. Buildings or sections of buildings used as exchanges, laboratories or studios shall be equipped with automatic sprinklers, as provided under subsections 221, 231 and 241. All buildings used for the storage or handling of film should be completely equipped with automatic sprinklers. 142. The spacing of sprinkler heads in all sections where film is handled shall not exceed one head for each 64 square feet, with heads and lines not over 8 feet apart ; provided that in the stage section of motion picture studios the spacing of sprinklers shall not exceed one head for each 80 square feet. In existing buildings where the spacing of sprinkler heads exceeds that specified above, the inspection department having jurisdiction may require the installation of additional heads wherever the hazard of some machine, process, or accumulation of film warrants such protection. 143. (a) It is recommended that two independent sources of water supply be provided, acceptable to the inspection department having jurisdiction. (b) Water supplies for automatic sprinklers shall be based on an estimate of 20 gallons a minute per head for 20 minutes for the total number of heads in one vault, plus 25 per cent of the number of heads in the largest fire area. (A fire area is regarded as an area cut off by brick or concrete walls having a minimum thickness of 8 inches; each opening in these walls to be protected by one self closing fire door, Class A type.) (c) Where gravity tanks form the primary source of supply they shall be elevated at least fifty feet above top sprinklers. Minimum capacity of gravity tanks shall be 10,000 gallons. (d) Due to alterations and resulting impairments customary in plants of this type sprinkler equipments shall be so arranged by the introduction of floor and auxiliary control valves, that maximum protection can be maintained at all times. 144. Every room in which film is