30 CFR § 75.1107-1 Fire-resistant hydraulic fluids and fire suppression devices on underground equipment.
(a)(1) Unattended electrically powered equipment used underground
which uses hydraulic fluid shall use approved fire-resistant hydraulic
(2) Except as provided in paragraph (a)(3) of this
section, within 24 production shift hours after being installed, unattended
electrically powered equipment used underground shall be equipped with a fire
suppression device which meets the applicable requirements of
§§75.1107-3 through 75.1107-16.
(3) Unattended enclosed motors, controls, transformers,
rectifiers, and other similar noncombustible electrically powered equipment
containing no flammable fluid may be protected:
(a)(3)(i) By an approved fire suppression device, or
(a)(3)(ii) Be located at least 2 feet from coal or other
combustible materials, or
(a)(3)(iii) Be separated from the coal or combustible
materials by a 4-inch-thick masonry firewall or equivalent; and be mounted on
a minimum 4-inch-thick noncombustible surface, platform, or equivalent. The
electrical cables at such equipment shall conform with the requirements of
Part 18 of this chapter (Bureau of Mines Schedule 2G) or
be in metal conduit.
(b) Attended electrically powered equipment used underground which
uses hydraulic fluid shall use approved fire-resistant hydraulic fluid unless
such equipment is protected by a fire suppression device which meets the
applicable requirements of §§75.1107-3--75.1107-16.
(c) For purpose of §§75.1107--75.1107-16 the
following underground equipment shall be considered attended equipment:
(1) Any machine or device regularly operated by a miner
assigned to operate such machine or device;
(2) Any machine or device which is mounted in the direct
line of sight of a jobsite which is located within 500 feet of such machine
or device and which jobsite is regularly occupied by a miner assigned to
perform job duties at such jobsite during each production shift.
(d) Machines and devices described under paragraph (c) of this
section must be inspected for fire and the input powerline deenergized when
workmen leave the area for more than 30 minutes.