(225 ILCS 705/5.22) (from Ch. 96 1/2, par. 522)
Sec. 5.22.
Where coal is broken down "on shift"; and while men are in the mine, with compressed air, or by some mechanical or chemical-mechanical device which does not emit spark or flame, he shall see that frequent examination for gas and other hazards is made by competent personnel.
(Source: Laws 1953, p. 701.)