(a) Methane monitors shall be installed on continuous mining machines
used in or beyond the last open crosscut.
(b) The monitors shall--
(1) Give warning at 1.0 percent methane.
(2) Automatically deenergize electrical equipment, except
power to monitoring equipment determined by MSHA to be intrinsically safe
under 30 CFR part 18, and prevent starting of such
equipment when methane levels reach 1.5 percent; and
(3) Automatically deenergize the equipment when power to a
sensor is interrupted.
(c) Sensing units of monitors shall be positioned at a location which
provides for the most effective measurement of methane.