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Electronic Code of Federal Regulations
Title 29: Labor
Subpart V—Power Transmission and Distribution
§1926.950 General requirements.
§1926.951 Tools and protective equipment.
§1926.952 Mechanical equipment.
§1926.953 Material handling.
§1926.954 Grounding for protection of employees.
§1926.955 Overhead lines.
§1926.956 Underground lines.
§1926.957 Construction in energized substations.
§1926.958 External load helicopters.
§1926.959 Lineman's body belts, safety straps, and lanyards.
§1926.960 Definitions applicable to this subpart.
Authority: 40 U.S.C. 3701; 29 U.S.C. 653, 655, 657; Secretary of Labor's Order Nos. 12-71 (36 FR 8754); 8-76 (41 FR 25059); 9-83 (48 FR 35736), 1-90 (55 FR 9033), 5-2007 (72 FR 31159), or 1-2012 (77 FR 3912), as applicable. Section 1926.951 also is issued under 29 CFR part 1911.
§1926.950 General requirements.
(a) Application. The occupational safety and health standards contained in this subpart V shall apply to the construction of electric transmission and distribution lines and equipment.
(1) As used in this subpart V the term “construction” includes the erection of new electric transmission and distribution lines and equipment, and the alteration, conversion, and improvement of existing electric transmission and distribution lines and equipment.
(2) Existing electric transmission and distribution lines and electrical equipment need not be modified to conform to the requirements of applicable standards in this subpart V, until such work as described in paragraph (a)(1) of this section is to be performed on such lines or equipment.
(3) The standards set forth in this subpart V provide minimum requirements for safety and health. Employers may require adherence to additional standards which are not in conflict with the standards contained in this subpart V.
(b) Initial inspections, tests, or determinations. (1) Existing conditions shall be determined before starting work, by an inspection or a test. Such conditions shall include, but not be limited to, energized lines and equipment, conditions of poles, and the location of circuits and equipment, including power and communication lines, CATV and fire alarm circuits.
(2) Electric equipment and lines shall be considered energized until determined to be deenergized by tests or other appropriate methods or means.
(3) Operating voltage of equipment and lines shall be determined before working on or near energized parts.
(c) Clearances. The provisions of paragraph (c) (1) or (2) of this section shall be observed.
(1) No employee shall be permitted to approach or take any conductive object without an approved insulating handle closer to exposed energized parts than shown in Table V-1, unless:
(i) The employee is insulated or guarded from the energized part (gloves or gloves with sleeves rated for the voltage involved shall be considered insulation of the employee from the energized part), or
(ii) The energized part is insulated or guarded from him and any other conductive object at a different potential, or
(iii) The employee is isolated, insulated, or guarded from any other conductive object(s), as during live-line bare-hand work.
(2) (i) The minimum working distance and minimum clear hot stick distances stated in Table V-1 shall not be violated. The minimum clear hot stick distance is that for the use of live-line tools held by linemen when performing live-line work.
(ii) Conductor support tools, such as link sticks, strain carriers, and insulator cradles, may be used: Provided, That the clear insulation is at least as long as the insulator string or the minimum distance specified in Table V-1 for the operating voltage.
Table V-1—Alternating Current—Minimum Distances
1Note: For 345-362 kv., 500-552 kv., and 700-765 kv., the minimum working distance and the minimum clear hot stick distance may be reduced provided that such distances are not less than the shortest distance between the energized part and a grounded surface.
(d) Deenergizing lines and equipment. (1) When deenergizing lines and equipment operated in excess of 600 volts, and the means of disconnecting from electric energy is not visibly open or visibly locked out, the provisions of paragraphs (d)(1) (i) through (vii) of this section shall be complied with:
(i) The particular section of line or equipment to be deenergized shall be clearly identified, and it shall be isolated from all sources of voltage.
(ii) Notification and assurance from the designated employee shall be obtained that:
(a) All switches and disconnectors through which electric energy may be supplied to the particular section of line or equipment to be worked have been deenergized;
(b) All switches and disconnectors are plainly tagged indicating that men are at work;
(c) And that where design of such switches and disconnectors permits, they have been rendered inoperable.
(iii) After all designated switches and disconnectors have been opened, rendered inoperable, and tagged, visual inspection or tests shall be conducted to insure that equipment or lines have been deenergized.
(iv) Protective grounds shall be applied on the disconnected lines or equipment to be worked on.
(v) Guards or barriers shall be erected as necessary to adjacent energized lines.
(vi) When more than one independent crew requires the same line or equipment to be deenergized, a prominent tag for each such independent crew shall be placed on the line or equipment by the designated employee in charge.
(vii) Upon completion of work on deenergized lines or equipment, each designated employee in charge shall determine that all employees in his crew are clear, that protective grounds installed by his crew have been removed, and he shall report to the designated authority that all tags protecting his crew may be removed.
(2) When a crew working on a line or equipment can clearly see that the means of disconnecting from electric energy are visibly open or visibly locked-out, the provisions of paragraphs (d)(i), and (ii) of this section shall apply:
(i) Guards or barriers shall be erected as necessary to adjacent energized lines.
(ii) Upon completion of work on deenergized lines or equipment, each designated employee in charge shall determine that all employees in his crew are clear, that protective grounds installed by his crew have been removed, and he shall report to the designated authority that all tags protecting his crew may be removed.
(e) Emergency procedures and first aid. (1) The employer shall provide training or require that his employees are knowledgeable and proficient in:
(i) Procedures involving emergency situations, and
(ii) First-aid fundamentals including resuscitation.
(2) In lieu of paragraph (e)(1) of this section the employer may comply with the provisions of §1926.50(c) regarding first-aid requirements.
(f) Night work. When working at night, spotlights or portable lights for emergency lighting shall be provided as needed to perform the work safely.
(g) Work near and over water. When crews are engaged in work over or near water and when danger of drowning exists, suitable protection shall be provided as stated in §1926.104, or §1926.105, or §1926.106.
(h) Sanitation facilities. The requirements of §1926.51 of subpart D of this part shall be complied with for sanitation facilities.
(i) Hydraulic fluids. All hydraulic fluids used for the insulated sections of derrick trucks, aerial lifts, and hydraulic tools which are used on or around energized lines and equipment shall be of the insulating type. The requirements for fire resistant fluids of §1926.302(d)(1) do not apply to hydraulic tools covered by this paragraph.
§1926.951 Tools and protective equipment.
(a) Protective equipment. (1)(i) Rubber protective equipment shall be in accordance with the provisions of the American National Standards Institute (ANSI), ANSI J6 series, as follows:
(ii) Rubber protective equipment shall be visually inspected prior to use.
(iii) In addition, an “air” test shall be performed for rubber gloves prior to use.
(iv) Protective equipment of material other than rubber shall provide equal or better electrical and mechanical protection.
(2) Protective hats shall be in accordance with the provisions of ANSI Z89.2-1971 Industrial Protective Helmets for Electrical Workers, Class B, and shall be worn at the jobsite by employees who are exposed to the hazards of falling objects, electric shock, or burns.
(b) Personal climbing equipment. (1) Body belts with straps or lanyards shall be worn to protect employees working at elevated locations on poles, towers, or other structures except where such use creates a greater hazard to the safety of the employees, in which case other safeguards shall be employed.
(2) Body belts and safety straps shall meet the requirements of §1926.959. In addition to being used as an employee safeguarding item, body belts with approved tool loops may be used for the purpose of holding tools. Body belts shall be free from additional metal hooks and tool loops other than those permitted in §1926.959.
(3) Body belts and straps shall be inspected before use each day to determine that they are in safe working condition.
(4)(i) Lifelines and lanyards shall comply with the provisions of §1926.502.
(ii) Safety lines are not intended to be subjected to shock loading and are used for emergency rescue such as lowering a man to the ground. Such safety lines shall be a minimum of one-half-inch diameter and three or four strand first-grade manila or its equivalent in strength (2,650 lb.) and durability.
(5) Defective ropes shall be replaced.
(c) Ladders. (1) Portable metal or conductive ladders shall not be used near energized lines or equipment except as may be necessary in specialized work such as in high voltage substations where nonconductive ladders might present a greater hazard than conductive ladders. Conductive or metal ladders shall be prominently marked as conductive and all necessary precautions shall be taken when used in specialized work.
(2) Hook or other type ladders used in structures shall be positively secured to prevent the ladder from being accidentally displaced.
(d) Live-line tools. (1) Only live-line tool poles having a manufacturer's certification to withstand the following minimum tests shall be used:
(i) 100,000 volts per foot of length for 5 minutes when the tool is made of fiberglass; or
(ii) 75,000 volts per foot of length for 3 minutes when the tool is made of wood; or
(iii) Other tests equivalent to paragraph (d) (i) or (ii) of this section as appropriate.
(2) All live-line tools shall be visually inspected before use each day. Tools to be used shall be wiped clean and if any hazardous defects are indicated such tools shall be removed from service.
(e) Measuring tapes or measuring ropes. Measuring tapes or measuring ropes which are metal or contain conductive strands shall not be used when working on or near energized parts.
(f) Handtools. (1) Switches for all powered hand tools shall comply with §1926.300(d).
(2) All portable electric handtools shall:
(i) Be equipped with three-wire cord having the ground wire permanently connected to the tool frame and means for grounding the other end; or
(ii) Be of the double insulated type and permanently labeled as “Double Insulated”; or
(iii) Be connected to the power supply by means of an isolating transformer, or other isolated power supply.
(3) All hydraulic tools which are used on or around energized lines or equipment shall use nonconducting hoses having adequate strength for the normal operating pressures. It should be noted that the provisions of §1926.302(d)(2) shall also apply.
(4) All pneumatic tools which are used on or around energized lines or equipment shall:
(i) Have nonconducting hoses having adequate strength for the normal operating pressures, and
(ii) Have an accumulator on the compressor to collect moisture.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 59 FR 40730, Aug. 9, 1994]
§1926.952 Mechanical equipment.
(a) General. (1) Visual inspections shall be made of the equipment to determine that it is in good condition each day the equipment is to be used.
(2) Tests shall be made at the beginning of each shift during which the equipment is to be used to determine that the brakes and operating systems are in proper working condition.
(3) No employer shall use any motor vehicle equipment having an obstructed view to the rear unless:
(i) The vehicle has a reverse signal alarm audible above the surrounding noise level or:
(ii) The vehicle is backed up only when an observer signals that it is safe to do so.
(b) Aerial lifts. (1) The provisions of §1926.556, subpart N of this part, shall apply to the utilization of aerial lifts.
(2) When working near energized lines or equipment, aerial lift trucks shall be grounded or barricaded and considered as energized equipment, or the aerial lift truck shall be insulated for the work being performed.
(3) Equipment or material shall not be passed between a pole or structure and an aerial lift while an employee working from the basket is within reaching distance of energized conductors or equipment that are not covered with insulating protective equipment.
(c) Cranes and other lifting equipment. (1) All equipment shall comply with subparts CC and O of this part, as applicable.
(2) Use of digger derricks must comply with §1910.269 (in addition to 29 CFR part 1926, subpart O) whenever 29 CFR part 1926, subpart CC, excludes such use in accordance with §1926.1400(c)(4).
(3) With the exception of equipment certified for work on the proper voltage, mechanical equipment shall not be operated closer to any energized line or equipment than the clearances set forth in §1926.950(c) unless, in addition to the requirements in §1926.1410:
(i) The mechanical equipment is insulated, or
(ii) The mechanical equipment is considered as energized.
Note to paragraph (c)(3): In accordance with 29 CFR 1926.1400(g), compliance with 29 CFR 1910.269(p) will be deemed compliance with §§1926.1407 through 1926.1411, including §1926.1410.
[44 FR 8577, Feb. 9, 1979 , 75 FR 48135, Aug. 9, 2010; 78 FR 32116, May 29, 2013]
§1926.953 Material handling.
(a) Unloading. Prior to unloading steel, poles, cross arms and similar material, the load shall be thoroughly examined to ascertain if the load has shifted, binders or stakes have broken or the load is otherwise hazardous to employees.
(b) Pole hauling. (1) During pole hauling operations, all loads shall be secured to prevent displacement and a red flag shall be displayed at the trailing end of the longest pole.
(2) Precautions shall be exercised to prevent blocking of roadways or endangering other traffic.
(3) When hauling poles during the hours of darkness, illuminated warning devices shall be attached to the trailing end of the longest pole.
(c) Storage. (1) No materials or equipment shall be stored under energized bus, energized lines, or near energized equipment, if it is practical to store them elsewhere.
(2) When materials or equipment are stored under energized lines or near energized equipment, applicable clearances shall be maintained as stated in Table V-1; and extraordinary caution shall be exercised when moving materials near such energized equipment.
(d) Tag line. Where hazards to employees exist tag lines or other suitable devices shall be used to control loads being handled by hoisting equipment.
(e) Oil filled equipment. During construction or repair of oil filled equipment the oil may be stored in temporary containers other than those required in §1926.152, such as pillow tanks.
(f) Framing. During framing operations, employees shall not work under a pole or a structure suspended by a crane, A-frame or similar equipment unless the pole or structure is adequately supported.
(g) Attaching the load. The hoist rope shall not be wrapped around the load. This provision shall not apply to electric construction crews when setting or removing poles.
§1926.954 Grounding for protection of employees.
(a) General. All conductors and equipment shall be treated as energized until tested or otherwise determined to be deenergized or until grounded.
(b) New construction. New lines or equipment may be considered deenergized and worked as such where:
(1) The lines or equipment are grounded, or
(2) The hazard of induced voltages is not present, and adequate clearances or other means are implemented to prevent contact with energized lines or equipment and the new lines or equipment.
(c) Communication conductors. Bare wire communication conductors on power poles or structures shall be treated as energized lines unless protected by insulating materials.
(d) Voltage testing. Deenergized conductors and equipment which are to be grounded shall be tested for voltage. Results of this voltage test shall determine the subsequent procedures as required in §1926.950(d).
(e) Attaching grounds. (1) When attaching grounds, the ground end shall be attached first, and the other end shall be attached and removed by means of insulated tools or other suitable devices.
(2) When removing grounds, the grounding device shall first be removed fromt the line or equipment using insulating tools or other suitable devices.
(f) Grounds shall be placed between work location and all sources of energy and as close as practicable to the work location, or grounds shall be placed at the work location. If work is to be performed at more than one location in a line section, the line section must be grounded and short circuited at one location in the line section and the conductor to be worked on shall be grounded at each work location. The minimum distance shown in Table V-1 shall be maintained from ungrounded conductors at the work location. Where the making of a ground is impracticable, or the conditions resulting therefrom would be more hazardous than working on the lines or equipment without grounding, the grounds may be omitted and the line or equipment worked as energized.
(g) Testing without grounds. Grounds may be temporarily removed only when necessary for test purposes and extreme caution shall be exercised during the test procedures.
(h) Grounding electrode. When grounding electrodes are utilized, such electrodes shall have a resistance to ground low enough to remove the danger of harm to personnel or permit prompt operation of protective devices.
(i) Grounding to tower. Grounding to tower shall be made with a tower clamp capable of conducting the anticipated fault current.
(j) Ground lead. A ground lead, to be attached to either a tower ground or driven ground, shall be capable of conducting the anticipated fault current and shall have a minimum conductance of No. 2 AWG copper.
§1926.955 Overhead lines.
(a) Overhead lines. (1) When working on or with overhead lines the provisions of paragraphs (a) (2) through (8) of this section shall be complied with in addition to other applicable provisions of this subpart.
(2) Prior to climbing poles, ladders, scaffolds, or other elevated structures, an inspection shall be made to determine that the structures are capable of sustaining the additional or unbalanced stresses to which they will be subjected.
(3) Where poles or structures may be unsafe for climbing, they shall not be climbed until made safe by guying, bracing, or other adequate means.
(4) Before installing or removing wire or cable, strains to which poles and structures will be subjected shall be considered and necessary action taken to prevent failure of supporting structures.
(5)(i) When setting, moving, or removing poles using cranes, derricks, gin poles, A-frames, or other mechanized equipment near energized lines or equipment, precautions shall be taken to avoid contact with energized lines or equipment, except in bare-hand live-line work, or where barriers or protective devices are used.
(ii) Equipment and machinery operating adjacent to energized lines or equipment shall comply with §1926.952(c)(2).
(6)(i) Unless using suitable protective equipment for the voltage involved, employees standing on the ground shall avoid contacting equipment or machinery working adjacent to energized lines or equipment.
(ii) Lifting equipment shall be bonded to an effective ground or it shall be considered energized and barricaded when utilized near energized equipment or lines.
(7) Pole holes shall not be left unattended or unguarded in areas where employees are currently working.
(8) Tag lines shall be of a nonconductive type when used near energized lines.
(b) Metal tower construction. (1) When working in unstable material the excavation for pad- or pile-type footings in excess of 5 feet deep shall be either sloped to the angle of repose as required in §1926.652 or shored if entry is required. Ladders shall be provided for access to pad- or pile-type footing excavations in excess of 4 feet.
(2) When working in unstable material provision shall be made for cleaning out auger-type footings without requiring an employee to enter the footing unless shoring is used to protect the employee.
(3)(i) A designated employee shall be used in directing mobile equipment adjacent to footing excavations.
(ii) No one shall be permitted to remain in the footing while equipment is being spotted for placement.
(iii) Where necessary to assure the stability of mobile equipment the location of use for such equipment shall be graded and leveled.
(4)(i) Tower assembly shall be carried out with a minimum exposure of employees to falling objects when working at two or more levels on a tower.
(ii) Guy lines shall be used as necessary to maintain sections or parts of sections in position and to reduce the possibility of tipping.
(iii) Members and sections being assembled shall be adequately supported.
(5) When assembling and erecting towers the provisions of paragraphs (b)(5) (i), (ii) and (iii) of this section shall be complied with:
(i) The construction of transmission towers and the erecting of poles, hoisting machinery, site preparation machinery, and other types of construction machinery shall conform to the applicable requirements of this part.
(ii) No one shall be permitted under a tower which is in the process of erection or assembly, except as may be required to guide and secure the section being set.
(iii) When erecting towers using hoisting equipment adjacent to energized transmission lines, the lines shall be deenergized when practical. If the lines are not deenergized, extraordinary caution shall be exercised to maintain the minimum clearance distances required by §1926.950(c), including Table V-1.
(6)(i) Erection cranes shall be set on firm level foundations and when the cranes are so equipped outriggers shall be used.
(ii) Tag lines shall be utilized to maintain control of tower sections being raised and positioned, except where the use of such lines would create a greater hazard.
(iii) The loadline shall not be detached from a tower section until the section is adequately secured.
(iv) Except during emergency restoration procedures erection shall be discontinued in the event of high wind or other adverse weather conditions which would make the work hazardous.
(v) Equipment and rigging shall be regularly inspected and maintained in safe operating condition.
(7) Adequate traffic control shall be maintained when crossing highways and railways with equipment as required by the provisions of §1926.200(g) (1) and (2).
(8) A designated employee shall be utilized to determine that required clearance is maintained in moving equipment under or near energized lines.
(c) Stringing or removing deenergized conductors. (1) When stringing or removing deenergized conductors, the provisions of paragraphs (c) (2) through (12) of this section shall be complied with.
(2) Prior to stringing operations a briefing shall be held setting forth the plan of operation and specifying the type of equipment to be used, grounding devices and procedures to be followed, crossover methods to be employed, and the clearance authorization required.
(3) Where there is a possibility of the conductor accidentally contacting an energized circuit or receiving a dangerous induced voltage buildup, to further protect the employee from the hazards of the conductor, the conductor being installed or removed shall be grounded or provisions made to insulate or isolate the employee.
(4)(i) If the existing line is deenergized, proper clearance authorization shall be secured and the line grounded on both sides of the crossover or, the line being strung or removed shall be considered and worked as energized.
(ii) When crossing over energized conductors in excess of 600 volts, rope nets or guard structures shall be installed unless provision is made to isolate or insulate the workman or the energized conductor. Where practical the automatic reclosing feature of the circuit interrupting device shall be made inoperative. In addition, the line being strung shall be grounded on either side of the crossover or considered and worked as energized.
(5) Conductors being strung in or removed shall be kept under positive control by the use of adequate tension reels, guard structures, tielines, or other means to prevent accidental contact with energized circuits.
(6) Guard structure members shall be sound and of adequate dimension and strength, and adequately supported.
(7)(i) Catch-off anchors, rigging, and hoists shall be of ample capacity to prevent loss of the lines.
(ii) The manufacturer's load rating shall not be exceeded for stringing lines, pulling lines, sock connections, and all load-bearing hardware and accessories.
(iii) Pulling lines and accessories shall be inspected regularly and replaced or repaired when damaged or when dependability is doubtful. The provisions of §1926.251(c)(4)(ii) (concerning splices) shall not apply.
(8) Conductor grips shall not be used on wire rope unless designed for this application.
(9) While the conductor or pulling line is being pulled (in motion) employees shall not be permitted directly under overhead operations, nor shall any employee be permitted on the crossarm.
(10) A transmission clipping crew shall have a minimum of two structures clipped in between the crew and the conductor being sagged. When working on bare conductors, clipping and tying crews shall work between grounds at all times. The grounds shall remain intact until the conductors are clipped in, except on dead end structures.
(11)(i) Except during emergency restoration procedures, work from structures shall be discontinued when adverse weather (such as high wind or ice on structures) makes the work hazardous.
(ii) Stringing and clipping operations shall be discontinued during the progress of an electrical storm in the immediate vicinity.
(12)(i) Reel handling equipment, including pulling and braking machines, shall have ample capacity, operate smoothly, and be leveled and aligned in accordance with the manufacturer's operating instructions.
(ii) Reliable communications between the reel tender and pulling rig operator shall be provided.
(iii) Each pull shall be snubbed or dead ended at both ends before subsequent pulls.
(d) Stringing adjacent to energized lines. (1) Prior to stringing parallel to an existing energized transmission line a competent determination shall be made to ascertain whether dangerous induced voltage buildups will occur, particularly during switching and ground fault conditions. When there is a possibility that such dangerous induced voltage may exist the employer shall comply with the provisions of paragraphs (d) (2) through (9) of this section in addition to the provisions of paragraph (c) of this §1926.955, unless the line is worked as energized.
(2) When stringing adjacent to energized lines the tension stringing method or other methods which preclude unintentional contact between the lines being pulled and any employee shall be used.
(3) All pulling and tensioning equipment shall be isolated, insulated, or effectively grounded.
(4) A ground shall be installed between the tensioning reel setup and the first structure in order to ground each bare conductor, subconductor, and overhead ground conductor during stringing operations.
(5) During stringing operations, each bare conductor, subconductor, and overhead ground conductor shall be grounded at the first tower adjacent to both the tensioning and pulling setup and in increments so that no point is more than 2 miles from a ground.
(i) The grounds shall be left in place until conductor installation is completed.
(ii) Such grounds shall be removed as the last phase of aerial cleanup.
(iii) Except for moving type grounds, the grounds shall be placed and removed with a hot stick.
(6) Conductors, subconductors, and overhead ground conductors shall be grounded at all dead-end or catch-off points.
(7) A ground shall be located at each side and within 10 feet of working areas where conductors, subconductors, or overhead ground conductors are being spliced at ground level. The two ends to be spliced shall be bonded to each other. It is recommended that splicing be carried out on either an insulated platform or on a conductive metallic grounding mat bonded to both grounds. When a grounding mat is used, it is recommended that the grounding mat be roped off and an insulated walkway provided for access to the mat.
(8)(i) All conductors, subconductors, and overhead ground conductors shall be bonded to the tower at any isolated tower where it may be necessary to complete work on the transmission line.
(ii) Work on dead-end towers shall require grounding on all deenergized lines.
(iii) Grounds may be removed as soon as the work is completed: Provided, That the line is not left open circuited at the isolated tower at which work is being completed.
(9) When performing work from the structures, clipping crews and all others working on conductors, subconductors, or overhead ground conductors shall be protected by individual grounds installed at every work location.
(e) Live-line bare-hand work. In addition to any other applicable standards contained elsewhere in this subpart all live-line bare-hand work shall be performed in accordance with the following requirements:
(1) Employees shall be instructed and trained in the live-line bare-hand technique and the safety requirements pertinent thereto before being permitted to use the technique on energized circuits.
(2) Before using the live-line bare-hand technique on energized high-voltage conductors or parts, a check shall be made of:
(i) The voltage rating of the circuit on which the work is to be performed;
(ii) The clearances to ground of lines and other energized parts on which work is to be performed; and
(iii) The voltage limitations of the aerial-lift equipment intended to be used.
(3) Only equipment designed, tested, and intended for live-line bare-hand work shall be used.
(4) All work shall be personally supervised by a person trained and qualified to perform live-line bare-hand work.
(5) The automatic reclosing feature of circuit interrupting devices shall be made inoperative where practical before working on any energized line or equipment.
(6) Work shall not be performed during the progress of an electrical storm in the immediate vicinity.
(7) A conductive bucket liner or other suitable conductive device shall be provided for bonding the insulated aerial device to the energized line or equipment.
(i) The employee shall be connected to the bucket liner by use of conductive shoes, leg clips, or other suitable means.
(ii) Where necessary, adequate electrostatic shielding for the voltage being worked or conductive clothing shall be provided.
(8) Only tools and equipment intended for live-line bare-hand work shall be used, and such tools and equipment shall be kept clean and dry.
(9) Before the boom is elevated, the outriggers on the aerial truck shall be extended and adjusted to stabilize the truck and the body of the truck shall be bonded to an effective ground, or barricaded and considered as energized equipment.
(10) Before moving the aerial lift into the work position, all controls (ground level and bucket) shall be checked and tested to determine that they are in proper working condition.
(11) Arm current tests shall be made before starting work each day, each time during the day when higher voltage is going to be worked and when changed conditions indicate a need for additional tests. Aerial buckets used for bare-hand live-line work shall be subjected to an arm current test. This test shall consist of placing the bucket in contact with an energized source equal to the voltage to be worked upon for a minimum time of three (3) minutes. the leakage current shall not exceed 1 microampere per kilo-volt of nominal line-to-line voltage. Work operations shall be suspended immediately upon any indication of a malfunction in the equipment.
(12) All aerial lifts to be used for live-line bare-hand work shall have dual controls (lower and upper) as required by paragraph (e)(12) (i) and (ii) of this section.
(i) The upper controls shall be within easy reach of the employee in the basket. If a two basket type lift is used access to the controls shall be within easy reach from either basket.
(ii) The lower set of controls shall be located near base of the boom that will permit over-ride operation of equipment at any time.
(13) Ground level lift control shall not be operated unless permission has been obtained from the employee in lift, except in case of emergency.
(14) Before the employee contacts the energized part to be worked on, the conductive bucket liner shall be bonded to the energized conductor by means of a positive connection which shall remain attached to the energized conductor until the work on the energized circuit is completed.
(15) The minimum clearance distances for live-line bare-hand work shall be as specified in Table V-2. These minimum clearance distances shall be maintained from all grounded objects and from lines and equipment at a different potential than that to which the insulated aerial device is bonded unless such grounded objects or other lines and equipment are covered by insulated guards. These distances shall be maintained when approaching, leaving, and when bonded to the energized circuit.
Table V-2—Minimum Clearance Distances for Live-Line Bare-Hand Work (Alternating Current)
1For 345-362kv., 500-552kv., and 700-765kv., the minimum clearance distance may be reduced provided the distances are not made less than the shortest distance between the energized part and a grounded surface.
(16) When approaching, leaving, or bonding to an energized circuit the minimum distances in Table V-2 shall be maintained between all parts of the insulated boom assembly and any grounded parts (including the lower arm or portions of the truck).
(17) When positioning the bucket alongside an energized bushing or insulator string, the minimum line-to-ground clearances of Table V-2 must be maintained between all parts of the bucket and the grounded end of the bushing or insulator string.
(18)(i) The use of handlines between buckets, booms, and the ground is prohibited.
(ii) No conductive materials over 36 inches long shall be placed in the bucket, except for appropriate length jumpers, armor rods, and tools.
(iii) Nonconductive-type handlines may be used from line to ground when not supported from the bucket.
(19) The bucket and upper insulated boom shall not be overstressed by attempting to lift or support weights in excess of the manufacturer's rating.
(20)(i) A minimum clearance table (as shown in table V-2) shall be printed on a plate of durable nonconductive material, and mounted in the buckets or its vicinity so as to be visible to the operator of the boom.
(ii) It is recommended that insulated measuring sticks be used to verify clearance distances.
§1926.956 Underground lines.
(a) Guarding and ventilating street opening used for access to underground lines or equipment. (1) Appropriate warning signs shall be promptly placed when covers of manholes, handholes, or vaults are removed. What is an appropriate warning sign is dependent upon the nature and location of the hazards involved.
(2) Before an employee enters a street opening, such as a manhole or an unvented vault, it shall be promptly protected with a barrier, temporary cover, or other suitable guard.
(3) When work is to be performed in a manhole or unvented vault:
(i) No entry shall be permitted unless forced ventilation is provided or the atmosphere is found to be safe by testing for oxygen deficiency and the presence of explosive gases or fumes;
(ii) Where unsafe conditions are detected, by testing or other means, the work area shall be ventilated and otherwise made safe before entry;
(iii) Provisions shall be made for an adequate continuous supply of air.
(b) Work in manholes. (1) While work is being performed in manholes, an employee shall be available in the immediate vicinity to render emergency assistance as may be required. This shall not preclude the employee in the immediate vicinity from occasionally entering a manhole to provide assistance, other than emergency. This requirement does not preclude a qualified employee, working alone, from entering for brief periods of time, a manhole where energized cables or equipment are in service, for the purpose of inspection, housekeeping, taking readings, or similar work if such work can be performed safely.
(2) When open flames must be used or smoking is permitted in manholes, extra precautions shall be taken to provide adequate ventilation.
(3) Before using open flames in a manhole or excavation in an area where combustible gases or liquids may be present, such as near a gasoline service station, the atmosphere of the manhole or excavation shall be tested and found safe or cleared of the combustible gases or liquids.
(c) Trenching and excavating. (1) During excavation or trenching, in order to prevent the exposure of employees to the hazards created by damage to dangerous underground facilities, efforts shall be made to determine the location of such facilities and work conducted in a manner designed to avoid damage.
(2) Trenching and excavation operations shall comply with §§1926.651 and 1926.652.
(3) When underground facilities are exposed (electric, gas, water, telephone, etc.) they shall be protected as necessary to avoid damage.
(4) Where multiple cables exist in an excavation, cables other than the one being worked on shall be protected as necessary.
(5) When multiple cables exist in an excavation, the cable to be worked on shall be identified by electrical means unless its identity is obvious by reason of distinctive appearance.
(6) Before cutting into a cable or opening a splice, the cable shall be identified and verified to be the proper cable.
(7) When working on buried cable or on cable in manholes, metallic sheath continuity shall be maintained by bonding across the opening or by equivalent means.
§1926.957 Construction in energized substations.
(a) Work near energized equipment facilities. (1) When construction work is performed in an energized substation, authorization shall be obtained from the designated, authorized person before work is started.
(2) When work is to be done in an energized substation, the following shall be determined:
(i) What facilities are energized, and
(ii) What protective equipment and precautions are necessary for the safety of personnel.
(3) Extraordinary caution shall be exercised in the handling of busbars, tower steel, materials, and equipment in the vicinity of energized facilities. The requirements set forth in §1926.950(c), shall be complied with.
(b) Deenergized equipment or lines. When it is necessary to deenergize equipment or lines for protection of employees, the requirements of §1926.950(d) shall be complied with.
(c) Barricades and barriers. (1) Barricades or barriers shall be installed to prevent accidental contact with energized lines or equipment.
(2) Where appropriate, signs indicating the hazard shall be posted near the barricade or barrier. These signs shall comply with §1926.200.
(d) Control panels. (1) Work on or adjacent to energized control panels shall be performed by designated employees.
(2) Precaution shall be taken to prevent accidental operation of relays or other protective devices due to jarring, vibration, or improper wiring.
(e) Mechanized equipment. (1) Use of vehicles, gin poles, cranes, and other equipment in restricted or hazardous areas shall at all times be controlled by designated employees.
(2) All mobile cranes and derricks shall be effectively grounded when being moved or operated in close proximity to energized lines or equipment, or the equipment shall be considered energized.
(3) Fenders shall not be required for lowboys used for transporting large electrical equipment, transformers, or breakers.
(f) Storage. The storage requirements of §1926.953(c) shall be complied with.
(g) Substation fences. (1) When a substation fence must be expanded or removed for construction purposes, a temporary fence affording similar protection when the site is unattended, shall be provided. Adequate interconnection with ground shall be maintained between temporary fence and permanent fence.
(2) All gates to all unattended substations shall be locked, except when work is in progress.
(h) Footing excavation. (1) Excavation for auger, pad and piling type footings for structures and towers shall require the same precautions as for metal tower construction (see §1926.955(b)(1)).
(2) No employee shall be permitted to enter an unsupported auger-type excavation in unstable material for any purpose. Necessary clean-out in such cases shall be accomplished without entry.
§1926.958 External load helicopters.
In all operations performed using a rotorcraft for moving or placing external loads, the provisions of §1926.551 of subpart N of this part shall be complied with.
§1926.959 Lineman's body belts, safety straps, and lanyards.
(a) General requirements. The requirements of paragraphs (a) and (b) of this section shall be complied with for all lineman's body belts, safety straps and lanyards acquired for use after the effective date of this subpart.
(1) Hardware for lineman's body belts, safety straps, and lanyards shall be drop forged or pressed steel and have a corrosive resistive finish tested to American Society for Testing and Materials B117-64 (50-hour test). Surfaces shall be smooth and free of sharp edges.
(2) All buckles shall withstand a 2,000-pound tensile test with a maximum permanent deformation no greater than one sixty-fourth inch.
(3) D rings shall withstand a 5,000-pound tensile test without failure. Failure of a D ring shall be considered cracking or breaking.
(4) Snaphooks shall withstand a 5,000-pound tensile test without failure. Failure of a snaphook shall be distortion sufficient to release the keeper.
(b) Specific requirements. (1)(i) All fabric used for safety straps shall withstand an A.C. dielectric test of not less than 25,000 volts per foot “dry” for 3 minutes, without visible deterioration.
(ii) All fabric and leather used shall be tested for leakage current and shall not exceed 1 milliampere when a potention of 3,000 volts is applied to the electrodes positioned 12 inches apart.
(iii) Direct current tests may be permitted in lieu of alternating current tests.
(2) The cushion part of the body belt shall:
(i) Contain no exposed rivets on the inside;
(ii) Be at least three (3) inches in width;
(iii) Be at least five thirty-seconds ( 5⁄32 ) inch thick, if made of leather; and
(iv) Have pocket tabs that extended at least 11⁄2 inches down and three (3) inches back of the inside of circle of each D ring for riveting on plier or tool pockets. On shifting D belts, this measurement for pocket tabs shall be taken when the D ring section is centered.
(3) A maximum of four (4) tool loops shall be so situated on the body belt that four (4) inches of the body belt in the center of the back, measuring from D ring to D ring, shall be free of tool loops, and any other attachments.
(4) Suitable copper, steel, or equivalent liners shall be used around bar of D rings to prevent wear between these members and the leather or fabric enclosing them.
(5) All stitching shall be of a minimum 42-pound weight nylon or equivalent thread and shall be lock stitched. Stitching parallel to an edge shall not be less than three-sixteenths ( 3⁄16 ) inch from edge of narrowest member caught by the thread. The use of cross stitching on leather is prohibited.
(6) The keeper of snaphooks shall have a spring tension that will not allow the keeper to begin to open with a weight of 21⁄2 pounds or less, but the keeper of snaphooks shall begin to open with a weight of four (4) pounds, when the weight is supported on the keeper against the end of the nose.
(7) Testing of lineman's safety straps, body belts and lanyards shall be in accordance with the following procedure:
(i) Attach one end of the safety strap or lanyard to a rigid support, the other end shall be attached to a 250-pound canvas bag of sand:
(ii) Allow the 250-pound canvas bag of sand to free fall 4 feet for (safety strap test) and 6 feet for (lanyard test); in each case stopping the fall of the 250-pound bag:
(iii) Failure of the strap or lanyard shall be indicated by any breakage, or slippage sufficient to permit the bag to fall free of the strap or lanyard. The entire “body belt assembly” shall be tested using one D ring. A safety strap or lanyard shall be used that is capable of passing the “impact loading test” and attached as required in paragraph (b)(7)(i) of this section. The body belt shall be secured to the 250-pound bag of sand at a point to simulate the waist of a man and allowed to drop as stated in paragraph (b)(7)(ii) of this section. Failure of the body belt shall be indicated by any breakage, or slippage sufficient to permit the bag to fall free of the body belt.
§1926.960 Definitions applicable to this subpart.
(a) Alive or live (energized). The term means electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of the earth in the vicinity. The term “live” is sometimes used in place of the term “current-carrying,” where the intent is clear, to avoid repetition of the longer term.
(b) Automatic circuit recloser. The term means a self-controlled device for automatically interrupting and reclosing an alternating current circuit with a predetermined sequence of opening and reclosing followed by resetting, hold closed, or lockout operation.
(c) Barrier. The term means a physical obstruction which is intended to prevent contact with energized lines or equipment.
(d) Barricade. The term means a physical obstruction such as tapes, screens, or cones intended to warn and limit access to a hazardous area.
(e) Bond. The term means an electrical connection from one conductive element to another for the purpose of minimizing potential differences or providing suitable conductivity for fault current or for mitigation of leak- age current and electrolytic action.
(f) Bushing. The term means an insulating structure including a through conductor, or providing a passageway for such a conductor, with provision for mounting on a barrier, conducting or otherwise, for the purpose of insulating the conductor from the barrier and conducting current from one side of the barrier to the other.
(g) Cable. The term means a conductor with insulation, or a stranded conductor with or without insulation and other coverings (single-conductor cable) or a combination of conductors insulated from one another (multiple-conductor cable).
(h) Cable sheath. The term means a protective covering applied to cables.
Note: A cable sheath may consist of multiple layers of which one or more is conductive.
(i) Circuit. The term means a conductor or system of conductors through which an electric current is intended to flow.
(j) Communication lines. The term means the conductors and their supporting or containing structures which are used for public or private signal or communication service, and which operate at potentials not exceeding 400 volts to ground or 750 volts between any two points of the circuit, and the transmitted power of which does not exceed 150 watts. When operating at less than 150 volts no limit is placed on the capacity of the system.
Note: Telephone, telegraph, railroad signal, data, clock, fire, police-alarm, community television antenna, and other systems conforming with the above are included. Lines used for signaling purposes, but not included under the above definition, are considered as supply lines of the same voltage and are to be so run.
(k) Conductor. The term means a material, usually in the form of a wire, cable, or bus bar suitable for carrying an electric current.
(l) Conductor shielding. The term means an envelope which encloses the conductor of a cable and provides an equipotential surface in contact with the cable insulation.
(m) Current-carrying part. The term means a conducting part intended to be connected in an electric circuit to a source of voltage. Non-current-carrying parts are those not intended to be so connected.
(n) Dead (deenergized). The term means free from any electrical connection to a source of potential difference and from electrical charges: Not having a potential difference from that of earth.
Note: The term is used only with reference to current-carrying parts which are sometimes alive (energized).
(o) Designated employee. The term means a qualified person delegated to perform specific duties under the conditions existing.
(p) Effectively grounded. The term means intentionally connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current-carrying capacity to prevent the buildup of voltages which may result in undue hazard to connected equipment or to persons.
(q) Electric line trucks. The term means a truck used to transport men, tools, and material, and to serve as a traveling workshop for electric power line construction and maintenance work. It is sometimes equipped with a boom and auxiliary equipment for setting poles, digging holes, and elevating material or men.
(r) Enclosed. The term means surrounded by a case, cage, or fence, which will protect the contained equipment and prevent accidental contact of a person with live parts.
(s) Equipment. This is a general term which includes fittings, devices, appliances, fixtures, apparatus, and the like, used as part of, or in connection with, an electrical power transmission and distribution system, or communication systems.
(t) Exposed. The term means not isolated or guarded.
(u) Electric supply lines. The term means those conductors used to transmit electric energy and their necessary supporting or containing structures. Signal lines of more than 400 volts to ground are always supply lines within the meaning of the rules, and those of less than 400 volts to ground may be considered as supply lines, if so run and operated throughout.
(v) Guarded. The term means protected by personnel, covered, fenced, or enclosed by means of suitable casings, barrier rails, screens, mats, platforms, or other suitable devices in accordance with standard barricading techniques designed to prevent dangerous approach or contact by persons or objects.
Note: Wires, which are insulated but not otherwise protected, are not considered as guarded.
(w) Ground. (Reference). The term means that conductive body, usually earth, to which an electric potential is referenced.
(x) Ground (as a noun). The term means a conductive connection whether intentional or accidental, by which an electric circuit or equipment is connected to reference ground.
(y) Ground (as a verb). The term means the connecting or establishment of a connection, whether by intention or accident of an electric circuit or equipment to reference ground.
(z) Grounding electrode (ground electrode). The term grounding electrode means a conductor embedded in the earth, used for maintaining ground potential on conductors connected to it, and for dissipating into the earth current conducted to it.
(aa) Grounding electrode resistance. The term means the resistance of the grounding electrode to earth.
(bb) Grounding electrode conductor (grounding conductor). The term means a conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode.
(cc) Grounded conductor. The term means a system or circuit conductor which is intentionally grounded.
(dd) Grounded system. The term means a system of conductors in which at least one conductor or point (usually the middle wire, or neutral point of transformer or generator windings) is intentionally grounded, either solidly or through a current-limiting device (not a current-interrupting device).
(ee) Hotline tools and ropes. The term means those tools and ropes which are especially designed for work on energized high voltage lines and equipment. Insulated aerial equipment especially designed for work on energized high voltage lines and equipment shall be considered hot line.
(ff) Insulated. The term means separated from other conducting surfaces by a dielectric substance (including air space) offering a high resistance to the passage of current.
Note: When any object is said to be insulated, it is understood to be insulated in suitable manner for the conditions to which it is subjected. Otherwise, it is within the purpose of this subpart, uninsulated. Insulating covering of conductors is one means of making the conductor insulated.
(gg) Insulation (as applied to cable). The term means that which is relied upon to insulate the conductor from other conductors or conducting parts or from ground.
(hh) Insulation shielding. The term means an envelope which encloses the insulation of a cable and provides an equipotential surface in contact with cable insulation.
(ii) Isolated. The term means an object that is not readily accessible to persons unless special means of access are used.
(jj) Manhole. The term means a subsurface enclosure which personnel may enter and which is used for the purpose of installing, operating, and maintaining equipment and/or cable.
(kk) Pulling tension. The term means the longitudinal force exerted on a cable during installation.
(ll) Qualified person. The term means a person who by reason of experience or training is familiar with the operation to be performed and the hazards involved.
(mm) Switch. The term means a device for opening and closing or changing the connection of a circuit. In these rules, a switch is understood to be manually operable, unless otherwise stated.
(nn) Tag. The term means a system or method of identifying circuits, systems or equipment for the purpose of alerting persons that the circuit, system or equipment is being worked on.
(oo) Unstable material. The term means earth material, other than running, that because of its nature or the influence of related conditions, cannot be depended upon to remain in place without extra support, such as would be furnished by a system of shoring.
(pp) Vault. The term means an enclosure above or below ground which personnel may enter and is used for the purpose of installing, operating, and/or maintaining equipment and/or cable.
(qq) Voltage. The term means the effective (rms) potential difference between any two conductors or between a conductor and ground. Voltages are expressed in nominal values. The nominal voltage of a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose of convenient designation. The operating voltage of the system may vary above or below this value.
(rr) Voltage of an effectively grounded circuit. The term means the voltage between any conductor and ground unless otherwise indicated.
(ss) Voltage of a circuit not effectively grounded. The term means the voltage between any two conductors. If one circuit is directly connected to and supplied from another circuit of higher voltage (as in the case of an autotransformer), both are considered as of the higher voltage, unless the circuit of lower voltage is effectively grounded, in which case its voltage is not determined by the circuit of higher voltage. Direct connection implies electric connection as distinguished from connection merely through electromagnetic or electrostatic induction.