(225 ILCS 705/15.04) (from Ch. 96 1/2, par. 1504)
    Sec. 15.04. Shut-off valves shall be installed, after the effective date of this Act, every 1,000 feet in all air lines and, in all branch air lines at a point near the main air lines.
(Source: Laws 1953, p. 701.)