45.1-161.219 - Volume of air.
§ 45.1-161.219. Volume of air.
A. The quantity of air passing through the last open crosscut shall be notless than 9,000 cubic feet per minute; provided, however, that the quantityof air reaching the last open crosscut in pillar-recovery sections may beless than 9,000 cubic feet per minute, if at least 9,000 cubic feet of airper minute is being delivered to the intake end of the pillar line.
B. The air current at working faces shall, under all conditions, have asufficient volume and velocity to readily dilute and carry away smoke fromblasting and any flammable or harmful gases and dust.
C. In longwall and shortwall mining systems:
1. The quantity of air shall be at least 30,000 cubic feet per minutereaching the working face unless otherwise approved by the Chief; and
2. The velocity of air provided to control dust at designated locations onthe longwall or shortwall face shall be maintained in accordance with theprovisions of the mine ventilation plan approved by the Mine Safety andHealth Administration.
D. Ventilation shall be maintained during the installation and removal ofmechanized mining equipment.
(Code 1950, §§ 45-4.1, 45-9, 45-12, 45-60.4, 45-74; 1954, c. 191; 1966, c.594, §§ 45.1-5, 45.1-56; 1968, c. 310; 1976, c. 598; 1978, c. 120; 1984, c.236; 1985, c. 448; 1987, c. 470; 1990, c. 963; 1993, c. 442; 1994, c. 28;1996, c. 774; 2005, c. 3.)