30 CFR § 57.22234 Actions at 1.0 percent methane (I-A, I-B, III, V-A, and V-B mines).
(a) If methane reaches 1.0 percent in the mine atmosphere,
ventilation changes shall be made to reduce the methane. Until such changes
are achieved--
(1) All persons other than competent persons necessary to
make the ventilation changes shall be withdrawn from affected areas;
(2) Electrical power shall be deenergized in affected
areas, except power to monitoring equipment determined by MSHA to be
intrinsically safe under 30 CFR part 18; and
(3) Diesel equipment shall be shut off or immediately
removed from the area.
(b) If methane reaches 1.0 percent at a main exhaust fan, electrical
power underground shall be deenergized, except power to monitoring equipment
determined by MSHA to be intrinsically safe under 30 CFR part 18, and all persons shall be withdrawn from the mine.
(c) If methane reaches 1.0 percent at a work place and there has been
a failure of the main ventilation system, all persons shall be withdrawn from
the mine.
[52 FR, 24941, July 1, 1987, as amended at 53 FR 9615, Mar. 24, 1988]
