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Subchapter 5. Electrical Safety Orders
Group 2. High-Voltage Electrical Safety Orders
Article 36. Work Procedures and Operating Procedures
§2943. Work on or in Proximity to Underground High-Voltage Cables, Conductors or Equipment.
(a) Application. This section applies to all work on or in proximity to underground high-voltage cables, conductors or equipment, and to the operations necessary to raise or lower cables, conductors or equipment to such underground locations.
(b) Manholes, Vaults, or Similar Structures.
(1) The employer shall determine if entry into the space is under Section 2943.1 for Enclosed Spaces or the permit required confined space under Article 108 of the General Industry or Article 37 of the Construction Safety Orders and shall comply with the appropriate safety orders.
(2) The employer shall ensure that employees use a ladder or other climbing device to enter and exit a manhole or subsurface vault exceeding 4 feet (1.22 meters) in depth. The employee shall not climb into or out of a manhole or vault by stepping on cables or hangers.
(3) Whenever the cover is removed from a manhole, vault, or similar structure:
(A) An employee shall be stationed at the surface as long as workers are in the structure, and
(B) warning devices shall be placed so as to warn vehicular or pedestrian traffic and shall not be removed until the cover is in place.
(4) Attendants for manholes and vaults. While work is being performed in a manhole or vault containing energized electric equipment, an employee with first-aid training shall be available on the surface in the immediate vicinity of the manhole or vault entrance to render emergency assistance.
(5) If entry is by Section 2943.1, the employee on the surface may enter a manhole or vault briefly to provide nonemergency assistance.
(6) If entry is by Section 2943.1 for the purpose of inspection, housekeeping, taking readings, or similar work, an employee working alone may enter, for brief periods of time, a manhole or vault where energized cables or equipment are in service if the employer can demonstrate that the employee will be protected from all electrical hazards.
(7) Communications. The employer shall ensure that employees maintain reliable communications, through two way radios or other equivalent means, among all employees involved in the job.
(8) Hoisting equipment. Equipment used to lower materials and tools into manholes or vaults shall be capable of supporting the weight to be lowered and shall be checked for defects before use.
(9) Clear the area of employees. Before anyone lowers tools or material into the opening for a manhole or vault, each employee working in the manhole or vault shall be clear of the area directly under the opening.
(10) When employees are working in an underground structure, the automatic circuit recloser on the circuit being worked shall be made non-automatic when:
(A) operating energized oil type switches from inside the structure,
(B) splicing energized underground cable,
(C) patching energized lead cable,
(D) relocating energized underground cable or equipment other than minor cable movements for additional clearance or routine maintenance such as cleaning cable, fire-proofing, replacing cable support blocks, etc.,
(E) filtering or replacing oil in energized underground equipment, or
(F) the supervisor in charge deems it necessary for the safety of the employees performing the work.
(11) When employees are in an underground structure where newly installed, rebuilt or modified cable or equipment is being energized for the first time, the automatic circuit recloser on the circuit involved shall be made non-automatic.
(12) Sheath continuity. When employees perform work on buried cable or on cable in a manhole or vault, the employer shall maintain metallic-sheath continuity, or the cable sheath shall be treated as energized.
(c) Trenching and Excavating.
(1) Trenching and excavation operations shall comply with the applicable provisions of the Construction Safety Orders.
(2) Where cable(s) exist in an excavation, such cable(s) shall be protected from physical damage during excavation.
(d) Duct Rods. The employer shall ensure that, if employees use duct rods, the employees install the duct rods in the direction presenting the least hazard to employees. The employer shall station an employee at the far end of the duct line being rodded to ensure that the employees maintain the required minimum approach distances.
(e) Multiple Cables. When multiple cables are present in a work area, the employer shall identify the cable to be worked by electrical means, unless its identity is obvious by reason of distinctive appearance or location or by other readily apparent means of identification. The employer shall protect cables other than the one being worked from damage.
(f) Moving Cables. The employer shall ensure that employees inspect energized cables to be moved for abnormalities.
EXCEPTION: When subsection (g)(2) of this section permits employees to perform work that could cause a fault, the employee shall be protected from possible effects of failure using shields or other devices capable of containing the adverse effect of the fault.
(g) Protection Against Faults.
(1) Cables with abnormalities. Where a cable in a manhole or vault has one or more abnormalities that could lead to a fault or be an indication of an impending fault, the employer shall deenergize the cable with the abnormality before any employee may work in the manhole or vault.
(A) The employer shall treat the following abnormalities as indications of impending faults unless the employer can demonstrate that the following conditions could not lead to a fault:
1. oil or compound leaking from cable or joints,
2. broken cable sheaths or joint sleeves,
3. hot localized surface temperatures of cables or joints, or
4. joints swollen beyond normal tolerance.
EXCEPTION to subsection (g)(1): When service-load conditions and a lack of feasible alternatives require that the cable remain energized. In that case, employees may enter the manhole or vault provided the employer protects them from the possible effects of a failure using shields or other devices that are capable of containing the adverse effects of a fault.
(2) If the work employees will perform in a manhole or vault could cause a fault in a cable, the employer shall deenergize that cable before any employee works in the manhole or vault. The following type of work practices are considered as work practices that could reasonably cause a fault:
(A) If the work practices used could foreseeably lead to the penetration of the cable; or
(B) If the work practices used could foreseeably place other damaging stresses on the cable jacket or insulation, such as bending beyond the manufacturer's specifications.
EXCEPTION to subsection (g)(2):
EXCEPTION No. 1: When service load conditions and a lack of feasible alternatives require that the cable remain energized. In that case, employees may enter the manhole or vault provided the employer protects them from the possible effects of a failure using shields or other devices that are capable of containing the adverse effects of a fault.
EXCEPTION No. 2: Qualified persons under the observance of a qualified electrical worker or qualified person authorized by the utility company may slice through or chip duct work, concrete asphalt, or similar material under the following conditions:
1. The chipping or slicing is performed with the use of hand tools, such as hammer and cold chisel, with movements that could potentially penetrate the cable directed away from the cable or limited by use of tool guard to prevent contact with the cable, and non-conductive barrier is inserted (if practicable) to protect the cable from penetration once sufficient material has been broken to make that action possible, or
2. Chipping of slicing performed with power tools using the following procedures: power tools are operated in a direction away from the energized cable unless tool guard are used to prevent contact with the cable; power tool are not used within 0.5 inch of an energized cable unless tool guards to prevent contact with energized cable are used; and a non-conductive protective barrier is inserted (if practicable) to protect the cable from penetration once sufficient material has been broken to make the action possible.
3. The removal of arc-proof covering or similar material from energized cable for cable identification and other purposes as long as the cable exhibits no visible abnormalities and the removal of this material is performed in a manner that will not impose damaging stresses on the cable insulation or jacket. For example, this work could include the use of a utility knife or similar tool to penetrate the tape (but not the cable jacket or insulation) so that the tape may then be removed by hand.
(h) Working on Cables, Conductors or Equipment Energized at 7,500 Volts or Less.
(1) Employees shall not be permitted to cut, splice, or move cables energized at 7,500 volts or less without first obtaining permission from the employee in charge.
(2) Before cutting into a cable or opening a splice, the cable shall be identified and verified to be the proper cable.
(3) Suitable rubber gloves with protectors and protective clothing in accordance with Section 2940.11 shall be worn when working on exposed conductors or equipment energized at 7,500 volts or less. Other exposed energized or grounded conductors or equipment in the work area, with which contact can be readily made, shall be covered with adequate protective devices, barricaded or otherwise isolated.
(4) Before breaking the electrical continuity of metallic sheaths of cables energized at 7,500 volts or less, both sides of the break shall be bonded together across the break.
(5) When working on exposed underground conductors or parts of equipment energized at 7,500 volts or less, adequate barriers or suitable protective covering shall be provided if a working space of 36 inches cannot be obtained.
(i) Working on Cables, Conductors or Equipment Energized in Excess of 7,500 Volts.
(1) When working on cables, conductors or equipment energized in excess of 7,500 volts, all exposed energized cables, conductors or equipment within reach of any part of the body shall be covered with suitable protective equipment in accordance with Sections 2940.6 and 2940.11 or barricaded.
(2) The only work permitted on cables, conductors or equipment energized in excess of 7,500 volts shall be:
(A) replacing fuses, operating switches, or other operations that do not require the employee to contact energized conductors or parts of equipment with any part of the employee's body,
(B) working on the exterior of such cables or equipment, provided all current-carrying parts are effectively covered by grounded shielding or metallic enclosures, and
(C) work in the high voltage compartment of padmounted transformers and similar equipment installed above ground, provided the work is done by suitable devices. Rubber gloves shall not be considered to be suitable devices.
(3) Cables energized in excess of 7,500 volts shall be moved only under the direction of the employee in charge. Before moving cables, they shall be examined for any defects which might result in failure if the cable were moved.
(j) Working on De-Energized Cables, Conductors or Equipment.
(1) De-energize cables, conductors, or equipment in accordance with the procedures in Section 2940.14 and Section 2940.15.
(2) When working on de-energized cables, conductors or equipment, all exposed energized conductors or equipment within reach of any part of the body, shall be covered with suitable protective equipment in accordance with Sections 2940.6 and 2940.11.
(3) Where more than one cable exists in an excavation, cables other than the one being worked on shall be physically protected as necessary.
(4) Where more than one cable exists in an excavation, the cable to be worked on shall be identified by electrical means or spiking unless its identity is obvious.
(5) Before cutting into a cable or opening a splice, the cable shall be identified and verified to be the proper cable.
(k) Grounding De-Energized Conductors or Equipment. Any exposed ungrounded part of conductors or equipment, not worked upon in accordance with the provisions of subsections (h) or (i) above, shall not be worked upon until the provisions in Sections 2940.14 and 2940.15 have been complied with.