A. All active workings shall be ventilated by a current of air containing not less than 19.5 volume percent of oxygen and no harmful quantities of other noxious or poisonous gases.

B. The volume and velocity of the current of air in all active workings shall be sufficient to dilute, render harmless and carry away flammable, explosive, noxious and harmful gases and dust, smoke, and explosive fumes.

History

Code 1950, § 45-60.3; 1954, c. 191; 1966, c. 594, § 45.1-63; 1968, c. 310; 1993, c. 442; 1994, c. 28; 1996, c. 774; 2005, c. 3.