30 CFR § 75.2
The following definitions apply in this part.
The Federal Mine Safety and Health Act of 1977.
Any place in a coal mine where miners are normally required to work or travel.
Adequate interrupting capacity
. The ability of an electrical
protective device, based upon its required and intended application, to
safely interrupt values of current in excess of its trip setting or
Coals with a volatile ratio equal to 0.12 or less. The volatile ratio is the volatile matter content divided by the volatile matter plus the fixed carbon.
Formal papers issued by the Mine Safety and
Health Administration which describe and illustrate the complete
assembly of electrical machinery or accessories which have met the
applicable requirements of 30 CFR part 18.
Certified or registered.
As applied to any person, a person certified or registered by the State in which the coal mine is located to perform duties prescribed by this part 75, except that in a State where no program of certification or registration is provided or where the program does not meet at least minimum Federal standards established by the Secretary, such certification or registration shall be by the Secretary.
. A device designed to open and close a
circuit by nonautomatic means and to open the circuit automatically at
a predetermined overcurrent value without damage to the device when
operated within its rating.
Includes areas of adjoining mines connected underground.
Filter Self-Rescuer (FSR).
A type of gas mask approved by MSHA and NIOSH under 42 CFR
part 84 for escape only from underground mines and which provides at least 1 hour of protection
against carbon monoxide.
Ground fault or grounded phase
. An unintentional connection between
an electric circuit and the grounding system.
Up to and including 660 volts, medium voltage means voltages from 661 to 1,000
volts; and high voltage means more than 1,000 volts.
An enclosure containing motor starting
circuits and equipment.
. The phase-to-phase or line-to-line root-mean-
square value assigned to a circuit or system for designation of its
voltage class, such as 480 or 4,160 volts. Actual voltage at which the
circuit or system operates may vary from the nominal voltage within a
range that permits satisfactory operation of equipment.
(1) As applied to electric face equipment, all electrically operated equipment taken into
or used inby the last open crosscut of an entry or a room of any coal mine the electrical parts of
which, including, but not limited to, associated electrical equipment, components, and accessories,
are designed, constructed, and installed, in accordance with the specifications of the Secretary, to
assure that such equipment will not cause a mine explosion or mine fire, and the other features of
which are designed and constructed, in accordance with the specifications of the Secretary, to
prevent, to the greatest extent possible, other accidents in the use of such equipment. The regulations
of the Secretary or the Director of the Bureau of Mines in effect on March 30, 1970, relating to the
requirements for investigation, testing, approval, certification, and acceptance of such equipment as
permissible shall continue in effect until modified or superseded by the Secretary, except that the
Secretary shall provide procedures, including, where feasible, testing, approval, certification, and
acceptance in the field by an authorized representative of the Secretary, to facilitate compliance by
an operator with the requirements of §75.500
within the periods prescribed in §75.500
(2) As applied to equipment other than permissible electric face equipment: (i) Equipment used in the
operation of a coal mine to which an approval plate, label, or other device is attached as authorized
by the Secretary and which meets specifications which are prescribed by the Secretary for the
construction and maintenance of such equipment and are designed to assure that such equipment will
not cause a mine explosion or a mine fire. (ii) The manner of use of equipment means the manner of
use prescribed by the Secretary.
As the context requires:
(1) An individual deemed qualified by the Secretary and designated by the operator to make tests
and examinations required by this part 75; and
(2) An individual deemed, in accordance with minimum requirements to be established by the
Secretary, qualified by training, education, and experience, to perform electrical work, to maintain
electrical equipment, and to conduct examinations and tests of all electrical equipment.
Dust collected with a sampling device approved by the Secretary and the
Secretary of Health and Human Services in accordance with part 74--Coal Mine Dust Personal
Sampler Units of this title. Sampling device approvals issued by the Secretary of the Interior and
Secretary of Health, Education, and Welfare are continued in effect.
Pulverized limestone, dolomite, gypsum, anhydrite, shale, adobe, or other inert material,
preferably light colored, 100 percent of which will pass through a sieve having 20 meshes per linear
inch and 70 percent or more of which will pass through a sieve having 200 meshes per linear inch;
the particles of which when wetted and dried will not cohere to form a cake which will not be
dispersed into separate particles by a light blast of air; and which does not contain more than 5
percent combustible matter or more than a total of 4 percent free and combined silica (SiO2
or, where the Secretary finds that such silica concentrations are not available, which does not contain
more than 5 percent of free and combined silica.
The Secretary of Labor or the Secretary's delegate.
Self-Contained Self-Rescuer (SCSR).
A type of closed-circuit, self-contained breathing apparatus
approved by MSHA and NIOSH under 42 CFR part 84 for escape only from underground mines.
. An abnormal connection of relatively low impedance,
whether made accidentally or intentionally, between two points of
Any place in a coal mine in which work of extracting coal from its natural deposit in
the earth is performed during the mining cycle.
The area of a coal mine inby the last open crosscut.
All areas of the coal mine from the loading point of the section to and including the
[57 FR 20913, May 15, 1992; 60 FR 30398, June 8, 1995]