[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: 30CFR57.2]

[Page 316-319]
 
                       TITLE 30--MINERAL RESOURCES
 
  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
 
PART 57--SAFETY AND HEALTH STANDARDS--UNDERGROUND METAL AND NONMETAL MINES--Table of Contents
 
                           Subpart A--General
 
Sec. 57.2  Definitions.

    The following definitions apply in this part, except in any subpart 
preceded by a separate set of definitions:
    Abandoned mine means all work has stopped on the mine premises and 
an office with a responsible person in charge is no longer maintained at 
the mine.
    Abandoned workings means deserted mine areas in which further work 
is not intended.
    Active workings means areas at, in, or around a mine or plant where 
men work or travel.
    American Table of Distances means the current edition of ``The 
American Table of Distances for Storage of Explosives'' published by the 
Institute of Makers of Explosives.
    Approved means tested and accepted for a specific purpose by a 
nationally recognized agency.
    Authorized person means a person approved or assigned by mine 
management to perform a specific type of duty or duties or to be at a 
specific location or locations in the mine.
    Auxiliary fan means a fan used to deliver air to working place off 
the main airstream; generally used with ventilation tubing.
    Barricaded means obstructed to prevent the passage of persons, 
vehicles, or flying materials.
    Blasting agent means any substance classified as a blasting agent by 
the Department of Transportation in 49 CFR 173.114(a) (44 FR 31182, May 
31, 1979) which is incorporated by reference. This document is available 
for inspection at each Metal and Nonmetal Mine Safety and Health 
District Office of the Mine Safety and Health Administration, and may be 
obtained from the U.S. Government Printing Office, Washington, DC 20402.
    Blasting area means the area near blasting operations in which 
concussion or flying material can reasonably be expected to cause 
injury.
    Blasting cap means a detonator which is initiated by a safety fuse.
    Blasting circuit means the electrical circuit used to fire one or 
more electric blasting caps.
    Blasting switch means a switch used to connect a power source to a 
blasting circuit.
    Booster fan means a fan installed in the main airstream or a split 
of the main airstream to increase airflow through a section or sections 
of a mine.
    `Booster means any unit of explosive or blasting agent used for the 
purpose of perpetuating or intensifying an initial detonation.
    Capped fuse means a length of safety fuse to which a blasting cap 
has been attached.
    Capped primer means a package or cartridge of explosives which is 
specifically designed to transmit detonation to other explosives and 
which contains a detonator.
    Circuit breaker means a device designed to open and close a circuit 
by nonautomatic means and to open the circuit automatically on a 
predetermined overcurrent setting without injury to itself when properly 
applied within its rating.
    Combustible means capable of being ignited and consumed by fire.
    Company official means a member of the company supervisory or 
technical staff.
    Competent person means a person having abilities and experience that 
fully qualify him to perform the duty to which he is assigned.
    Conductor means a material, usually in the form of a wire, cable, or 
bus bar, capable of carrying an electric current.
    Delay connector means a nonelectric short interval delay device for 
use in delaying blasts which are initiated by detonating cord.
    Detonating cord means a flexible cord containing a solid core of 
high explosives.
    Detonator means any device containing a detonating charge that is

[[Page 317]]

used to initiate an explosive and includes but is not limited to 
blasting caps, electric blasting caps and nonelectric instantaneous or 
delay blasting caps.
    Distribution box means a portable apparatus with an enclosure 
through which an electric circuit is carried to one or more cables from 
a single incoming feed line; each cable circuit being connected through 
individual overcurrent protective devices.
    Electric blasting cap means a detonator designed for and capable of 
being initiated by means of an electric current.
    Electrical grounding means to connect with the ground to make the 
earth part of the circuit.
    Employee means a person who works for wages or salary in the service 
of an employer.
    Employer means a person or organization which hires one or more 
persons to work for wages or salary.
    Escapeway means a passageway by which persons may leave a mine.
    Explosive means any substance classified as an explosive by the 
Department of Transportation in 49 CFR 173.53, 173.88 and 173.100 which 
are incorporated by reference. Title 49 CFR is available for inspection 
at each Metal and Nonmetal Mine Safety and Health District Office of the 
Mine Safety and Health Administration, and may be obtained from the U.S. 
Government Printing Office, Washington, DC 20402.
    Face or bank means that part of any mine where excavating is 
progressing or was last done.
    Flammable means capable of being easily ignited and of burning 
rapidly.
    Flash point means the minimum temperature at which sufficient vapor 
is released by a liquid or solid to form a flammable vapor-air mixture 
at atmospheric pressure.
    Highway means any public street, public alley or public road.
    High potential means more than 650 volts.
    Hoist means a power driven windlass or drum used for raising ore, 
rock, or other material from a mine, and for lowering or raising persons 
and material.
    Igniter cord means a fuse, cordlike in appearance, which burns 
progressively along its length with an external flame at the zone of 
burning, and is used for lighting a series of safety fuses in the 
desired sequence.
    Insulated means separated from other conducting surfaces by a 
dielectric substance permanently offering a high resistance to the 
passage of current and to disruptive discharge through the substance. 
When any substance is said to be insulated, it is understood to be 
insulated in a manner suitable for the conditions to which it is 
subjected. Otherwise, it is, within the purpose of this definition, 
uninsulated. Insulating covering is one means for making the conductor 
insulated.
    Insulation means a dielectric substance offering a high resistance 
to the passage of current and to a disruptive discharge through the 
substance.
    Lay means the distance parallel to the axis of the rope in which a 
strand makes one complete turn about the axis of the rope
    Low potential means 650 volts or less.
    Magazine means a facility for the storage of explosives, blasting 
agents, or detonators.
    Main fan means a fan that controls the entire airflow of the mine, 
or the airflow of one of the major air circuits.
    Major electrical installation means an assemblage of stationary 
electrical equipment for the generation, transmission, distribution, or 
conversion of electrical power.
    Mantrip means a trip on which persons are transported to and from a 
work area.
    Mill includes any ore mill, sampling works, concentrator, and any 
crushing, grinding, or screening plant used at, and in connection with, 
an excavation or mine.
    Mine opening means any opening or entrance from the surface into a 
mine.
    Misfire means the complete or partial failure of a blasting charge 
to explode as planned.
    Multipurpose dry-chemical fire extinguisher means a listed or 
approved multipurpose dry-chemical fire extinguisher having a minimum 
rating of 2-A:10-B:C, by Underwriters Laboratories, Inc., and containing 
a minimum of 4.5 pounds of dry-chemical agent.

[[Page 318]]

    Non-electric delay blasting cap means a detonator with an integral 
delay element and capable of being initiated by miniaturized detonating 
cord.
    Overburden means material of any nature, consolidated or 
unconsolidated, that overlies a deposit of useful materials or ores that 
are to be mined.
    Overload means that current which will cause an excessive or 
dangerous temperature in the conductor or conductor insulation.
    Permissible means a machine, material, apparatus, or device which 
has been investigated, tested, and approved by the Bureau of Mines or 
the Mine Safety and Health Administration, and is maintained in 
permissible condition.
    Potable water means water which shall meet the applicable minimum 
health requirements for drinking water established by the State or 
community in which the mine is located or by the Environmental 
Protection Agency in 40 CFR part 141, pages 169-182 revised as of July 
1, 1977. Where no such requirements are applicable, the drinking water 
provided shall conform with the Public Health Service Drinking Water 
Standards, 42 CFR part 72, subpart J, pages 527-533, revised as of 
October 1, 1976. Publications to which references are made in this 
definition are hereby made a part hereof. These incorporated 
publications are available for inspection at each Metal and Nonmetal 
Mine Safety and Health District Office of the Mine Safety and Health 
Administration.
    Powder chest means a substantial, nonconductive portable container 
equipped with a lid and used at blasting sites for explosives other than 
blasting agents.
    Primer means a unit, package, or cartridge of explosives used to 
initiate other explosives or blasting agents, and which contains a 
detonator.
    Reverse-current protection means a method or device used on direct-
current circuits or equipment to prevent the flow of current in a 
reverse direction.
    Roll protection means a framework, safety canopy or similar 
protection for the operator when equipment overturns.
    Safety can means an approved container, of not over 5 gallons 
capacity, having a spring-closing lid and spout cover.
    Safety fuse means a flexible cord containing an internal burning 
medium by which fire is conveyed at a continuous and uniform rate for 
the purpose of firing blasting caps or a black powder charge.
    Safety switch means a sectionalizing switch that also provides shunt 
protection in blasting circuits between the blasting switch and the shot 
area.
    Scaling means removal of insecure material from a face or highwall.
    Secondary safety connection means a second connection between a 
conveyance and rope, intended to prevent the conveyance from running 
away or falling in the event the primary connection fails.
    Shaft means a vertical or inclined shaft, a slope, incline, or 
winze.
    Short circuit means an abnormal connection of relatively low 
resistance, whether made accidentally or intentionally, between two 
points of difference potential in a circuit.
    Slurry (as applied to blasting). See ``Water gel.''
    Stray current means that portion of a total electric current that 
flows through paths other than the intended circuit.
    Substantial construction means construction of such strength, 
material, and workmanship that the object will withstand all reasonable 
shock, wear, and usage to which it will be subjected.
    Suitable means that which fits, and has the qualities or 
qualifications to meet a given purpose, occasion, condition, function, 
or circumstance.
    Travelway means a passage, walk or way regularly used and designated 
for persons to go from one place to another.
    Water gel or Slurry (as applied to blasting) means an explosive or 
blasting agent containing substantial portions of water.
    Wet drilling means the continuous application of water through the 
central hole of hollow drill steel to the bottom of the drill hole.
    Working level (WL) means any combination of the short-lived radon 
daughters in one liter of air that will result in ultimate emission of 
1.3x105

[[Page 319]]

MeV (million electron volts) of potential alpha energy, and exposure to 
these radon daughters over a period of time is expressed in terms of 
``working level months'' (WLM). Inhalation of air containing a radon 
daughter concentration of 1 WL for 173 hours results in an exposure of 1 
WLM.''
    Working place means any place in or about a mine where work is being 
performed.

[50 FR 4082, Jan. 29, 1985, as amended at 50 FR 20100, May 14, 1985; 53 
FR 32526, Aug. 25, 1988; 60 FR 35695, July 11, 1995]

                               Procedures