ART. 1 . . . Each backboard must be midway between the sidelines, with the plane of its front face perpendicular to the floor, parallel to the end line, and 4 feet from it.
ART. 2 . . . The upper edge of the backboard must be 13 feet above the floor for the rectangular, and 12 feet 8 inches for the fan-shaped. The backboard must be protected from spectators to a distance of at least 3 feet at each end.