[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR75.2]
[Page 454-456]
TITLE 30--MINERAL RESOURCES
CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
PART 75--MANDATORY SAFETY STANDARDS--UNDERGROUND COAL MINES--Table of Contents
Subpart A--General
Sec. 75.2 Definitions.
The following definitions apply in this part.
Act. The Federal Mine Safety and Health Act of 1977.
Active workings. 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
melting point.
Anthracite. 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.
Approval documentation. 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.
Circuit-interrupting device. 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.
Coal mine. 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.
[[Page 455]]
Ground fault or grounded phase. An unintentional connection between
an electric circuit and the grounding system.
Low voltage. 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.
Motor-starter enclosure. An enclosure containing motor starting
circuits and equipment.
Nominal voltage. 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.
Permissible. (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 Sec. 75.500 within
the periods prescribed in Sec. 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.
Qualified person. 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.
Respirable dust. 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.
Rock dust. 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.
Secretary. 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
[[Page 456]]
MSHA and NIOSH under 42 CFR part 84 for escape only from underground
mines.
Short circuit. An abnormal connection of relatively low impedance,
whether made accidentally or intentionally, between two points of
different potential.
Working face. 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.
Working place. The area of a coal mine inby the last open crosscut.
Working section. All areas of the coal mine from the loading point
of the section to and including the working faces.
[57 FR 20913, May 15, 1992, as amended at 60 FR 30401, June 8, 1995; 67
FR 11001, Mar. 11, 2002]