California Code of Regulations › Title 8 - Industrial Relations › Division 1 - Department of Industrial Relations › Chapter 4 - Division of Industrial Safety › Subchapter 17 - Mine Safety Orders › Article 47 - Electrical Equipment and Practices › General › Section 7183 - Federal Electrical Standards

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a) Except as provided herein, the Bureau of
						Mines Mandatory Electricity Standards published July 31, 1969, February 25,
						1970 and December 8, 1970 are adopted as part of these orders and read as
						follows:
EXCEPTION: In no case shall the minimum requirements be
						  less than those established in the Electrical Safety Orders, T-8, CAC and Part
						  3, T-24, CAC.
GENERAL
(1) (12-1) Circuits shall be protected
						against excessive overload by fuses or circuits breakers of the correct type
						and capacity.
(2) (12-2) Electric
						equipment and circuits shall be provided wit switches or other controls. Such
						switches or controls shall be of approved design and construction and shall be
						properly installed.
(3) (12-3)
						Individual overload protection and short circuit protection shall be provided
						for the trailing cables of mobile equipment.
(4) (12-7) Trailing cables and power-cable
						connections to junction boxes shall not be made or broken while
						energized.
(5) (12-11)
						High-potential transmission cables shall be covered, insulated, or placed to
						prevent contact with low-potential circuits.
(6) (12-14) Shovel trailing cables shall not
						be moved with the shovel dipper unless cable slings or sleds are
						used.
(7) (12-16) Electrical
						equipment shall be deenergized before work is done on such equipment. Switches
						shall be locked out or other measures taken which shall prevent the equipment
						from being energized without the knowledge of the individuals working on it.
						Such locks, or preventative devices shall be removed only by the persons who
						installed them or by authorized personnel.
(8) (12-17) Power circuits shall be
						deenergized before work is done on such circuits unless hotline tools are used.
						Suitable warning signs shall be posted by the individuals who are to do the
						work. Switches shall be locked out or other measures taken which shall prevent
						the power circuits from being energized without the knowledge of the
						individuals working on them. Such locks, signs, or preventative devices shall
						be removed only by the person who installed them or by authorized
						personnel.
(9) (12-18) All
						switches, automatic cutouts, or other control devices shall be located or
						marked as to clearly indicate the equipment controlled by them, and switches
						(excepting magnetic switches) shall indicate whether they are open or
						closed.
(10) (12-20) Dry wooden
						platforms, insulating mats, or other electrically-nonconductive material shall
						be kept in place at all switchboards and power-control switches where shock
						hazards exist. However, metal plates on which a person normally would stand and
						which are kept at the same potential as the grounded, metal,
						noncurrent-carrying parts of the power switches to be operated may be
						used.
(11) (12-21) Suitable danger
						signs shall be posted at all major electrical installations.
(12) (12-23) Electrical connections and
						resistor grids that are difficult or impractical to insulate shall be guarded,
						unless protection is provided by location.
(13) (12-25) All metal enclosing or encasing
						electrical circuits shall be grounded or provided with equivalent protection.
						This requirement does not apply to battery-operated equipment.
(14) (12-26) Metal fencing and metal
						buildings enclosing transformers and switchgear shall be grounded.
(15) (12-27) Frame grounding or equivalent
						protection shall be provided for mobile equipment powered through trailing
						cables.
(16) (12-28) Continuity and
						resistance of grounding systems shall be tested immediately after
						installation.
(17) (12-30) When a
						potentially dangerous condition is found it shall be corrected before equipment
						or wiring is energized.
(18)
						(12-33) Hand-held electric tools shall not be operated at high potential
						voltages.
(19) (12-36) Fuses shall
						not be removed or replaced by hand in an energized circuit, and they shall not
						otherwise be removed or replaced in an energized circuit unless equipment and
						techniques especially designed to prevent electric shock are provided and used
						for such purpose.
(20) (12-37) Fuse
						tongs or hot line tools shall be used when fuses are removed or replaced in
						high-potential circuits.
(21)
						(12-40) Operating controls shall be installed so that they can be operated
						without danger of contact with energized conductors.
(22) (12-41) Switches and starting boxes
						shall be of safe design and capacity.
(23) (12-45) Overhead high-potential
						powerlines lines shall be installed as specified by the Electrical Safety
						Orders and Part 3, T-24, CAC.
(24)
						(12-47) Guy wires of poles supporting high-potential conductors shall be
						equipped with insulators installed near the pole end.
(25) (12-48) Telegraph, telephone, or signal
						wires shall not be installed on the same crossarm with power conductors. When
						carried on poles supporting powerlines, they shall be installed as specified by
						the Electrical Safety Orders and Part 3, T-24, CAC.
(26) (4-10) Power wires and cables shall be
						adequately insulated. Flexible cords and cables shall not be used as a
						substitute for fixed wiring and shall be adequately protected when subject to
						physical damage.
(27) (4-11)
						Abandoned electrical circuits shall be de-energized and isolated so that they
						cannot become energized inadvertently.
SURFACE ONLY
(28) (12-65) Powerlines, including trolley
						wires, and telephone circuits shall be protected against short circuits and
						lightning.
(29) (12-66) Where
						metallic tools or equipment can come in contact with trolley wires or bare
						powerlines, the lines shall be guarded or deenergized.
(30) (12-67) Transformers shall be totally
						enclosed, located on poles or shall be enclosed in compliance with the
						Electrical Safety Orders.
(31)
						(12-68) Transformer enclosures shall be kept locked against unauthorized
						entry.
(32) Provisions for
						preventing accidents due to overhead high-voltage lines shall be in conformance
						with the High-Voltage Electrical Safety Orders, Article 86, which reads:
Article 86. Provisions for Preventing Accidents
						  Due to Proximity of Overhead Lines
2946. Provisions for Preventing Accidents Due to
						  Proximity to Overhead Lines.
(a)
						General. No person, firm, or corporation, or agent of same, shall require or
						permit any employee to perform any function in proximity to energize
						high-voltage lines; to enter upon any land, building, or other premises and
						thereto engage in any excavation, demolition, construction, repair, or other
						operation; or to erect, install, operate, or store in or upon such premises any
						tools, machinery, equipment, materials, or structures (including scaffolding,
						house moving, well drilling, pile driving, or hoisting equipment) unless and
						until danger from accidental contact with said high-voltage lines has been
						effectively guarded against.
(b)
						Clearances or Safeguards Required. Except where electrical distribution and
						transmission lines have been deenergized and visibly grounded or effective
						barriers have been erected to prevent physical and arcing contacts with the
						high-voltage lines, the following provisions shall be met:
(1) Over Lines. The operation, erection, or
						handling of tools, machinery, apparatus, supplies, or materials, or any part
						thereof, over energized high-voltage lines shall be prohibited.
(2) Equipment and Materials in Use. The
						operation, erection, or handling of tools, machinery equipment, apparatus,
						materials, or supplies, or any part thereof within the minimum clearances from
						energized lines set forth in Table X shall be prohibited.
Table X
Required Clearances from
									 Overhead High-Voltage Lines
Nominal Voltage
								  (Phase to Phase)
Minimum Required
								  Clearance (Feet)
.......................... 750-
								  50,000
..........................10
Over
..........................
								  50,000- 75,000
..........................11
Over
..........................
								  75,000- 125,000
..........................13
Over
..........................125,000-
								  175,000
..........................15
Over
..........................175,000-
								  250,000
..........................17
Over
..........................250,000-
								  370,000
..........................21
Over
..........................370,000-
								  550,000
..........................27
Over
..........................550,000-1,000,000
..........................42
(3) Transportation or Transit. The
						transportation or transit of any tool, machinery, equipment, or apparatus, or
						the moving of any house or other building in proximity to overhead high-voltage
						lines shall be expressly prohibited if at any time during such transportation
						or transit such tool, machinery, equipment, apparatus, or building or any part
						thereof, can come closer to high-voltage lines than the minimum clearances set
						forth in Table Y.
Except where the boom of boom-type equipment is lowered
						  and no load is imposed thereon, the equipment in transit shall conform to the
						  minimum required clearances set forth in Table X.
Table Y
Required Clearances from
									 Energized High-Voltage Conductors (While in Transit)
Nominal Voltage
								  (Phase to Phase)
Minimum Required
								  Clearance (Feet)
.......................... 750-
								  50,000
..........................6
Over
..........................
								  50,000- 345,000
..........................10
Over
..........................345,000-
								  750,000
..........................16
Over
..........................750,000-1,000,000
..........................20
(4) Storage. The storage of tools, machinery,
						equipment, supplies, materials, or apparatus under, by, or near energized
						high-voltage lines is hereby expressly prohibited if at any time during such
						handling or other manipulation it is possible to bring such tools, machinery,
						equipment, supplies, materials, or apparatus, or any part thereof, within the
						minimum required clearances from high-voltage lines as set forth in Table
						X.
(c) The specified
						clearance shall not be reduced by movement due to any strains impressed (by
						attachments or otherwise) upon the structures supporting the high-voltage line
						or upon any equipment, fixtures, or attachments thereon.
(d) Insulated cage-type boom guards, boom
						stops, insulating links, or proximity warning devices may be used on cranes,
						but the use of such devices shall not alter the required clearances set forth
						in Table X.
(e) Any overhead
						conductor shall be considered to be energized unless and until the person
						owning or operating such line verifies that the line is not energized, and the
						line is visibly grounded at the work site.
2947. Warning Signs Required. The owner, agent, or
						  employer responsible for the operations of equipment shall post and maintain in
						  plain view of the operator and driver on each crane, derrick, power shovel,
						  drilling rig, hay loader, hay stacker, pile driver, or similar apparatus, a
						  durable warning sign legible at 12 feet reading:
"UNLAWFUL TO OPERATE THIS EQUIPMENT WITHIN 10 FEET OF
						  HIGH-VOLTAGE LINES OF 50,000 VOLTS OR LESS."
In addition to the above wording, the following
						  statement in small lettering shall be provided on the warning sign: "For
						  Minimum Clearances Of High-Voltage Lines In Excess of 50,000 Volts. See Article
						  86, Title 8, High-Voltage Electrical Safety Orders."
2948. Notification to the Operators of
						  High-Voltage Lines and Responsibility for Safeguards.
When any operations are to be performed, tools, or
						  materials handled, or equipment is to be moved or operated within the specified
						  clearances of any energized high-voltage lines, the person or persons
						  responsible for the work to be done shall promptly notify the operator of the
						  high-voltage line of the work to be performed and shall be responsible for the
						  completion of the safety measures as required by Order 2946(b) before
						  proceeding with any work which would impair the aforesaid clearance.
2949. Special Exemptions.
The provisions of the foregoing Orders 2946 through
						  2948 shall not apply to the construction, reconstruction, maintenance, or
						  operation of any energized high-voltage overhead lines or their supporting
						  structure or appurtenances by qualified electrical workers, nor to work
						  performed in proximity to high-voltage lines by qualified persons using
						  approved equipment and work procedures.
UNDERGROUND ONLY
(33) (12-80) Trolley wires and bare power
						conductors shall be guarded at man-trip loading and unloading points, and at
						shaft stations. Open unguarded trolley wires shall be placed not less than 9
						feet above the track, or not less than 6 inches outside of the rail and not
						less than 7 feet above the rail.
(34) (12-82) Powerlines shall be well
						separated or insulated from waterlines, telephone lines, and air
						lines.
(35) (12-85) Transformer
						stations shall be enclosed to prevent persons from unintentionally or
						inadvertently contacting energized parts.