(a) Poles, wires, conduits and other appurtenances which may cause openings to be accessible to rats shall be blocked from rat usage, where such openings are not ratproofed as provided in the preceding section, by installing sheet metal guards of 24 gauge or heavier.
(b) Such guards, when used on horizontal pipes, wires, conduits or other appurtenances, shall be placed in a vertical position and shall be snugly fitted around the pipe, wire, conduit or other appurtenances. Such guard shall measure not less than 12 inches beyond and on all sides of the pipe, wire, conduit or other appurtenances where the intervening space between the wall and pipe permits, and shall extend 30 inches in an upward direction and 12 inches in a downward direction, and shall be securely fastened to the pipe, wire, conduit or other appurtenance and also to the adjacent wall wherever practicable, so that the guard will remain in a vertical position at all times.
(c) Such guards, when used on vertical pipes, wires, conduits or other appurtenances, shall be fitted snugly around the pipe, wire, conduit or other appurtenance, shall be placed in a horizontal position at a right angle thereto, and shall extend horizontally from the pipe, wire, conduit or other appurtenance for a minimum distance of 12 inches beyond and on all sides of the pipe, wire, conduit or other appurtenance where the intervening space between pipe and wall permits, and shall be securely fastened to the pipe, wire, conduit or other appurtenance and also to the adjacent wall wherever practicable, in such manner that the guard will remain in a horizontal position at all times.
(1964 Code, § 19-360)