THEATERS, AUDIENCE AREAS OF

MOTION PICTURE AND TELEVISION STUDIOS, AND SIMILAR LOCATIONS A. General 520-1. Scope. This article covers all buildings or that part of a building or structure designed or used for presentation, dramatic, musical, motion picture projection, or similar purposes and to specific audience seating areas within motion picture or television studios. 520-2. Motion Picture Projectors. Motion picture equipment and its installation and use shall comply with Article 540. 520-3. Sound Reproduction. Sound-reproducing equipment and its installation shall comply with Article 640. 520-4. Wiring Methods. The fixed wiring method shall be metal raceways, nonmetallic raceways encased in at least 2 inches (50.8 mm) of concrete, Type MI cable, or Type MC cable. Exception No. 1: The wiring for portable switchboards, stage set lighting, stage effects, and other wiring not fixed as to location shall be permitted with approved flexible cords and cables as provided elsewhere in Article 520. Fastening such cables and cords by uninsulated staples or nailing shall not be permitted. Exception No. 2: As provided in Article 640 for sound recording, in Article 800 for communication circuits, in Article 725 for Class 2 and Class 3 remote-control and signaling circuits, and in Article 760 for fire protective signaling circuits. Exception No. 3: Nonmetallic-sheathed cable, Type AC cable, electrical nonmetallic tubing, and rigid nonmetallic conduit shall be permitted to be installed in those buildings or portions thereof that are not required to be of fire-rated construction by the applicable building code. 520-5. Number of Conductors in Raceway. The number of conductors permitted in any metal conduit, rigid nonmetallic conduit as permitted in this article, or electrical metallic tubing for border or stage pocket circuits or for remote-control conductors shall not exceed the percentage fill shown in Table 1 of Chapter 9. Where contained within an auxiliary gutter or a