- Part Number:1910
- Part Number Title:Occupational Safety and Health Standards
- Subpart:1910 Subpart R
- Subpart Title:Special Industries
- Standard Number:
- Title:Electric power generation, transmission, and distribution.
- Appendix:
- GPO Source:
Note to paragraph (a)(1)(i)(A): The types of installations covered by this paragraph include the generation, transmission, and distribution installations of electric utilities, as well as equivalent installations of industrial establishments. Subpart S of this part covers supplementary electric generating equipment that is used to supply a workplace for emergency, standby, or similar purposes only. (See paragraph (a)(1)(i)(B) of this section.)
Note 1 to paragraph (a)(1)(ii)(B): The Occupational Safety and Health Administration considers work practices conforming to §§1910.332 through 1910.335 as complying with the electrical safety-related work-practice requirements of §1910.269 identified in Table 1 of appendix A-2 to this section, provided that employers are performing the work on a generation or distribution installation meeting §§1910.303 through 1910.308. This table also identifies provisions in §1910.269 that apply to work by qualified persons directly on, or associated with, installations of electric power generation, transmission, and distribution lines or equipment, regardless of compliance with §§1910.332 through 1910.335.
Note 2 to paragraph (a)(1)(ii)(B): The Occupational Safety and Health Administration considers work practices performed by qualified persons and conforming to §1910.269 as complying with §§1910.333(c) and 1910.335.
Note to paragraph (a)(2)(ii): For the purposes of this section, a person must have the training required by paragraph (a)(2)(ii) of this section to be considered a qualified person.
Note to paragraph (a)(2)(v)(C): The Occupational Safety and Health Administration considers tasks that are performed less often than once per year to necessitate retraining before the performance of the work practices involved.
The employer shall ensure that each employee has demonstrated proficiency in the work practices involved before that employee is considered as having completed the training required by paragraph (a)(2) of this section.
Note 1 to paragraph (a)(2)(viii): Though they are not required by this paragraph, employment records that indicate that an employee has successfully completed the required training are one way of keeping track of when an employee has demonstrated proficiency.
Note 2 to paragraph (a)(2)(viii): For an employee with previous training, an employer may determine that that employee has demonstrated the proficiency required by this paragraph using the following process:
(1) Confirm that the employee has the training required by paragraph (a)(2) of this section,
(2) Use an examination or interview to make an initial determination that the employee understands the relevant safety-related work practices before he or she performs any work covered by this section, and
(3) Supervise the employee closely until that employee has demonstrated proficiency as required by this paragraph.
Note to paragraph (a)(3)(i)(A): This paragraph requires the host employer to obtain information listed in paragraphs (a)(4)(i) through (a)(4)(v) of this section if it does not have this information in existing records.
Note to paragraph (a)(3)(i)(B): For the purposes of this paragraph, the host employer need only provide information to contract employers that the host employer can obtain from its existing records through the exercise of reasonable diligence. This paragraph does not require the host employer to make inspections of worksite conditions to obtain this information.
Note to paragraph (a)(3)(i)(C): This paragraph requires the host employer to obtain information about the design and operation of its installation that contract employers need to make required assessments if it does not have this information in existing records.
Note to paragraph (a)(3)(i)(D): For the purposes of this paragraph, the host employer need only provide information to contract employers that the host employer can obtain from its existing records through the exercise of reasonable diligence. This paragraph does not require the host employer to make inspections of worksite conditions to obtain this information.
Note to paragraph (c)(4): The briefing must address all the subjects listed in paragraph (c)(2) of this section.
Note to paragraph (d)(1): Installations in electric power generation facilities that are not an integral part of, or inextricably commingled with, power generation processes or equipment are covered under §1910.147 and Subpart S of this part.
Note to paragraph (d)(2)(v)(E): If normal work schedule and operation records demonstrate adequate inspection activity and contain the required information, no additional certification is required.
Note to paragraph (d)(3)(ii)(F): For specific provisions covering accident prevention tags, see §1910.145.
Note to paragraph (d)(5): See also paragraph (d)(7) of this section, which requires that the second notification take place before the machine or equipment is reenergized.
Lockout devices shall be attached in a manner that will hold the energy isolating devices in a "safe" or "off" position.
Tagout devices shall be affixed in such a manner as will clearly indicate that the operation or movement of energy isolating devices from the "safe" or "off" position is prohibited.
Whenever outside servicing personnel are to be engaged in activities covered by paragraph (d) of this section, the on-site employer and the outside employer shall inform each other of their respective lockout or tagout procedures, and each employer shall ensure that his or her personnel understand and comply with restrictions and prohibitions of the energy control procedures being used.
Note to paragraph (d): Lockout and tagging procedures that comply with paragraphs (c) through (f) of §1910.147 will also be deemed to comply with paragraph (d) of this section if the procedures address the hazards covered by paragraph (d) of this section.
Note to paragraph (e)(4): The determination called for in this paragraph may consist of a check of the conditions that might foreseeably be in the enclosed space. For example, the cover could be checked to see if it is hot and, if it is fastened in place, could be loosened gradually to release any residual pressure. An evaluation also needs to be made of whether conditions at the site could cause a hazardous atmosphere, such as an oxygen-deficient or flammable atmosphere, to develop within the space.
Note to paragraph (e)(7): See paragraph (t) of this section for additional requirements on attendants for work in manholes and vaults.
Ventilation, and monitoring for flammable gases or vapors. If flammable gases or vapors are detected or if an oxygen deficiency is found, forced-air ventilation shall be used to maintain oxygen at a safe level and to prevent a hazardous concentration of flammable gases and vapors from accumulating. A continuous monitoring program to ensure that no increase in flammable gas or vapor concentration above safe levels occurs may be followed in lieu of ventilation if flammable gases or vapors are initially detected at safe levels.
Note to paragraph (e)(11): See the definition of "hazardous atmosphere" for guidance in determining whether a specific concentration of a substance is hazardous.
Open flames. If open flames are used in enclosed spaces, a test for flammable gases and vapors shall be made immediately before the open flame device is used and at least once per hour while the device is used in the space. Testing shall be conducted more frequently if conditions present in the enclosed space indicate that once per hour is insufficient to detect hazardous accumulations of flammable gases or vapors.
Note to paragraph (e)(14): See the definition of "hazardous atmosphere" for guidance in determining whether a specific concentration of a substance is hazardous.
Note to paragraph (e): Entries into enclosed spaces conducted in accordance with the permit-space entry requirements of paragraphs (d) through (k) of §1910.146 are considered as complying with paragraph (e) of this section.
Note to paragraph (g)(1) of this section: Paragraph (h) of § 1910.132 sets employer payment obligations for the personal protective equipment required by this section, including, but not limited to, the fall protection equipment required by paragraph (g)(2) of this section, the electrical protective equipment required by paragraph (l)(3) of this section, and the flame-resistant and arc-rated clothing and other protective equipment required by paragraph (l)(8) of this section.
Note to paragraph (g)(2)(iii)(D): Distortion of the snaphook sufficient to release the keeper is considered to be tensile failure of a snaphook.
Note to paragraphs (g)(2)(iii)(G)(1) and (g)(2)(iii)(G)(2): Positioning straps that pass direct-current tests at equivalent voltages are considered as meeting this requirement.
A flammability test in accordance with Table R-2.
Table R-2—Flammability Test
Test method | Criteria for passing the test |
---|---|
Vertically suspend a 500-mm (19.7-inch) length of strapping supporting a 100-kg (220.5-lb) weight Use a butane or propane burner with a 76-mm (3-inch) flame. |
Any flames on the positioning strap shall self extinguish. The positioning strap shall continue to support the 100-kg (220.5-lb) mass. |
Direct the flame to an edge of the strapping at a distance of 25 mm (1 inch) | |
Remove the flame after 5 seconds | |
Wait for any flames on the positioning strap to stop burning |
Note to paragraph (g)(2)(iii) of this section: When used by employees weighing no more than 140 kg (310 lbm) fully equipped, body belts and positioning straps that conform to American Society of Testing and Materials Standard Specifications for Personal Climbing Equipment, ASTM F887-12e1, are deemed to be in compliance with paragraph (g)(2)(iii) of this section.
Note to paragraph (g)(2)(iv)(A): Appendix F to this section contains guidelines for inspecting work-positioning equipment.
Note to paragraph (g)(2)(iv)(B): Fall protection equipment rigged to arrest falls is considered a fall arrest system and must meet the applicable requirements for the design and use of those systems. Fall protection equipment rigged for work positioning is considered work-positioning equipment and must meet the applicable requirements for the design and use of that equipment.
Until March 31, 2015, a qualified employee climbing or changing location on poles, towers, or similar structures need not use fall protection equipment, unless conditions, such as, but not limited to, ice, high winds, the design of the structure (for example, no provision for holding on with hands), or the presence of contaminants on the structure, could cause the employee to lose his or her grip or footing. On and after April 1, 2015, each qualified employee climbing or changing location on poles, towers, or similar structures must use fall protection equipment unless the employer can demonstrate that climbing or changing location with fall protection is infeasible or creates a greater hazard than climbing or changing location without it.
Note 1 to paragraphs (g)(2)(iv)(C)(2) and (g)(2)(iv)(C)(3): These paragraphs apply to structures that support overhead electric power transmission and distribution lines and equipment. They do not apply to portions of buildings, such as loading docks, or to electric equipment, such as transformers and capacitors. Subpart D of this part contains the duty to provide fall protection associated with walking and working surfaces.
Note 2 to paragraphs (g)(2)(iv)(C)(2) and (g)(2)(iv)(C)(3): Until the employer ensures that employees are proficient in climbing and the use of fall protection under paragraph (a)(2)(viii) of this section, the employees are not considered "qualified employees" for the purposes of paragraphs (g)(2)(iv)(C)(2) and (g)(2)(iv)(C)(3) of this section. These paragraphs require unqualified employees (including trainees) to use fall protection any time they are more than 1.2 meters (4 feet) above the ground.
Note to paragraph (g)(2)(iv)(E): Wood-pole fall-restriction devices meeting American Society of Testing and Materials Standard Specifications for Personal Climbing Equipment, ASTM F887-12e1, are deemed to meet the anchorage-strength requirement when they are used in accordance with manufacturers' instructions.
Special ladders and platforms. Portable ladders used on structures or conductors in conjunction with overhead line work need not meet §1910.23(c)(4) and (9). Portable ladders and platforms used on structures or conductors in conjunction with overhead line work shall meet the following requirements:
Note to paragraph (i)(4)(i): If any hazardous defects are present, no operating pressure is safe, and the hydraulic or pneumatic equipment involved may not be used. In the absence of defects, the maximum rated operating pressure is the maximum safe pressure.
Note to paragraph (i)(4)(iii): Use of hydraulic lines that do not have check valves and that have a separation of more than 10.7 meters (35 feet) between the oil reservoir and the upper end of the hydraulic system promotes the formation of a partial vacuum.
Note to paragraph (j)(1)(i): Live-line tools using rod and tube that meet ASTM F711-02 (2007), Standard Specification for Fiberglass-Reinforced Plastic (FRP) Rod and Tube Used in Live Line Tools, are deemed to comply with paragraph (j)(1) of this section.
Note to paragraph (j)(2): Guidelines for the examination, cleaning, repairing, and inservice testing of live-line tools are specified in the Institute of Electrical and Electronics Engineers' IEEE Guide for Maintenance Methods on Energized Power Lines, IEEE Std 516-2009.
Note to paragraph (k)(2)(ii): Paragraphs (u)(1) and (v)(3) of this section specify the size of the working space.
Note to paragraph (l)(3)(ii): See Appendix B to this section for information on how to calculate the maximum anticipated per-unit transient overvoltage, phase-to-ground, when the employer uses portable protective gaps to reduce maximum transient overvoltages.
Note 1 to paragraph (l)(8)(ii): Appendix E to this section provides guidance on estimating available heat energy. The Occupational Safety and Health Administration will deem employers following the guidance in Appendix E to this section to be in compliance with paragraph (l)(8)(ii) of this section. An employer may choose a method of calculating incident heat energy not included in Appendix E to this section if the chosen method reasonably predicts the incident energy to which the employee would be exposed.
Note 2 to paragraph (l)(8)(ii): This paragraph does not require the employer to estimate the incident heat energy exposure for every job task performed by each employee. The employer may make broad estimates that cover multiple system areas provided the employer uses reasonable assumptions about the energy-exposure distribution throughout the system and provided the estimates represent the maximum employee exposure for those areas. For example, the employer could estimate the heat energy just outside a substation feeding a radial distribution system and use that estimate for all jobs performed on that radial system.
Note to paragraph (l)(8)(iii) of this section: This paragraph prohibits clothing made from acetate, nylon, polyester, rayon and polypropylene, either alone or in blends, unless the employer demonstrates that the fabric has been treated to withstand the conditions that may be encountered by the employee or that the employee wears the clothing in such a manner as to eliminate the hazard involved.
Note to paragraph (l)(8)(iv)(C): This paragraph does not apply to conductors that are capable of carrying, without failure, the maximum available fault current for the time the circuit protective devices take to interrupt the fault.
Note to paragraph (l)(8): See Appendix E to this section for further information on the selection of appropriate protection.
The employer shall ensure that devices used by employees to close circuits under load conditions are designed to safely carry the current involved.
Table R-3—AC Live-Line Work Minimum Approach Distance
[The minimum approach distance (MAD; in meters) shall conform to the following equations.]
For phase-to-phase system voltages of 50 V to 300 V: 1 | |
MAD = avoid contact | |
For phase-to-phase system voltages of 301 V to 5 kV: 1 | |
MAD = M + D, where | |
D = 0.02 m | the electrical component of the minimum approach distance. |
M = 0.31 m for voltages up to 750 V and 0.61 m otherwise | the inadvertent movement factor. |
For phase-to-phase system voltages of 5.1 kV to 72.5 kV:1 4 | |
MAD = M + AD, where | |
M = 0.61 m | the inadvertent movement factor. |
A = the applicable value from Table R-5 | the altitude correction factor. |
D = the value from Table R-4 corresponding to the voltage and exposure or the value of the electrical component of the minimum approach distance calculated using the method provided in appendix B to this section | the electrical component of the minimum approach distance. |
For phase-to-phase system voltages of more than 72.5 kV, nominal:2 4 | |
MAD = 0.3048(C + a)VL-GTA + M | |
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VL-G = phase-to-ground rms voltage, in kV | |
T = maximum anticipated per-unit transient overvoltage; for phase-to-ground exposures, T equals TL-G, the maximum per-unit transient overvoltage, phase-to-ground, determined by the employer under paragraph (l)(3)(ii) of this section; for phase-to-phase exposures, T equals 1.35TL-G + 0.45 | |
A = altitude correction factor from Table R-5 | |
M = 0.31 m, the inadvertent movement factor | |
a = saturation factor, as follows: |
Phase-to-Ground Exposures | |||||
VPeak = TL-GVL-G√2 | 635 kV or less | 635.1 to 915 kV | 915.1 to 1,050 kV | More than 1,050 kV | |
a | 0 | (VPeak-635)/140,000 | (VPeak-645)/135,000 | (VPeak-675)/125,000 | |
Phase-to-Phase Exposures3 | |||||
VPeak = (1.35TL-G + 0.45)VL-G√2 | 630 kV or less | 630.1 to 848 kV | 848.1 to 1,131 kV | 1,131.1 to 1,485 kV | More than 1,485 kV |
a | 0 | (VPeak-630)/155,000 | (VPeak-633.6)/152,207 | (VPeak-628)/153,846 | (VPeak-350.5)/203,666 |
1 Employers may use the minimum approach distances in Table R-6. If the worksite is at an elevation of more than 900 meters (3,000 feet), see footnote 1 to Table R-6.
2 Employers may use the minimum approach distances in Table R-7, except that the employer may not use the minimum approach distances in Table R-7 for phase-to-phase exposures if an insulated tool spans the gap or if any large conductive object is in the gap. If the worksite is at an elevation of more than 900 meters (3,000 feet), see footnote 1 to Table R-7. Employers may use the minimum approach distances in Table 14 through Table 21 in appendix B to this section, which calculated MAD for various values of T, provided the employer follows the notes to those tables.
3 Use the equations for phase-to-ground exposures (with VPeak for phase-to-phase exposures) unless the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap.
4 Until March 31, 2015, employers may use the minimum approach distances in Table 6 through Table 13 in Appendix B to this section.
Table R-4—Electrical Component of the Minimum Approach Distance at 5.1 to 72.5 kV
[D; In meters]
Nominal voltage (kV) phase-to-phase |
Phase-to-ground exposure | Phase-to-phase exposure |
---|---|---|
D (m) | D (m) | |
5.1 to 15.0 | 0.04 | 0.07 |
15.1 to 36.0 | 0.16 | 0.28 |
36.1 to 46.0 | 0.23 | 0.37 |
46.1 to 72.5 | 0.39 | 0.59 |
Table R-5—Altitude Correction Factor
Altitude above sea level (m) |
A |
---|---|
0 to 900 | 1.00 |
901 to 1,200 | 1.02 |
1,201 to 1,500 | 1.05 |
1,501 to 1,800 | 1.08 |
1,801 to 2,100 | 1.11 |
2,101 to 2,400 | 1.14 |
2,401 to 2,700 | 1.17 |
2,701 to 3,000 | 1.20 |
3,001 to 3,600 | 1.25 |
3,601 to 4,200 | 1.30 |
4,201 to 4,800 | 1.35 |
4,801 to 5,400 | 1.39 |
5,401 to 6,000 | 1.44 |
Table R-6—Alternative Minimum Approach Distances for Voltages of 72.5 kV and Less1
Nominal voltage (kV) phase-to-phase |
Distance | |||
---|---|---|---|---|
Phase-to-ground exposure | Phase-to-phase exposure | |||
m | ft | m | ft | |
0.050 to 0.3002 | Avoid Contact | Avoid Contact | ||
0.301 to 0.7502 | 0.33 | 1.09 | 0.33 | 1.09 |
0.751 to 5.0 | 0.63 | 2.07 | 0.63 | 2.07 |
5.1 to 15.0 | 0.65 | 2.14 | 0.68 | 2.24 |
15.1 to 36.0 | 0.77 | 2.53 | 0.89 | 2.92 |
36.1 to 46.0 | 0.84 | 2.76 | 0.98 | 3.22 |
46.1 to 72.5 | 1.00 | 3.29 | 1.20 | 3.94 |
1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work.
2 For single-phase systems, use voltage-to-ground.
Table R-7—Alternative Minimum Approach Distances for Voltages of More Than 72.5 kV1 2 3
Voltage range phase to phase (kV) | Phase-to-ground exposure | Phase-to-phase exposure | ||
---|---|---|---|---|
m | ft | m | ft | |
72.6 to 121.0 | 1.13 | 3.71 | 1.42 | 4.66 |
121.1 to 145.0 | 1.30 | 4.27 | 1.64 | 5.38 |
145.1 to 169.0 | 1.46 | 4.79 | 1.94 | 6.36 |
169.1 to 242.0 | 2.01 | 6.59 | 3.08 | 10.10 |
242.1 to 362.0 | 3.41 | 11.19 | 5.52 | 18.11 |
362.1 to 420.0 | 4.25 | 13.94 | 6.81 | 22.34 |
420.1 to 550.0 | 5.07 | 16.63 | 8.24 | 27.03 |
550.1 to 800.0 | 6.88 | 22.57 | 11.38 | 37.34 |
1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work.
2 Employers may use the phase-to-phase minimum approach distances in this table provided that no insulated tool spans the gap and no large conductive object is in the gap.
3 The clear live-line tool distance shall equal or exceed the values for the indicated voltage ranges.
Table R-8—DC Live-Line Minimum Approach Distance with Overvoltage Factor1
[In meters]
Maximum anticipated per-unit transient overvoltage |
Distance (m) maximum line-to-ground voltage (kV) |
||||
---|---|---|---|---|---|
250 | 400 | 500 | 600 | 750 | |
1.5 or less | 1.12 | 1.60 | 2.06 | 2.62 | 3.61 |
1.6 | 1.17 | 1.69 | 2.24 | 2.86 | 3.98 |
1.7 | 1.23 | 1.82 | 2.42 | 3.12 | 4.37 |
1.8 | 1.28 | 1.95 | 2.62 | 3.39 | 4.79 |
1 The distances specified in this table are for air, bare-hand, and live-line tool conditions. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work.
Table R-9—Assumed Maximum Per-Unit Transient Overvoltage
Voltage range (kV) |
Type of current (ac or dc) |
Assumed maximum per-unit transient overvoltage |
---|---|---|
72.6 to 420.0 | ac | 3.5 |
420.1 to 550.0 | ac | 3.0 |
550.1 to 800.0 | ac | 2.5 |
250 to 750 | dc | 1.8 |
Note to paragraph (n)(1): This paragraph covers grounding of generation, transmission, and distribution lines and equipment when this section requires protective grounding and whenever the employer chooses to ground such lines and equipment for the protection of employees.
Note to paragraph (n)(3): Appendix C to this section contains guidelines for establishing the equipotential zone required by this paragraph. The Occupational Safety and Health Administration will deem grounding practices meeting these guidelines as complying with paragraph (n)(3) of this section.
Note to paragraph (n)(4): American Society for Testing and Materials Standard Specifications for Temporary Protective Grounds to Be Used on De-Energized Electric Power Lines and Equipment, ASTM F855-09, contains guidelines for protective grounding equipment. The Institute of Electrical Engineers Guide for Protective Grounding of Power Lines, IEEE Std 1048-2003, contains guidelines for selecting and installing protective grounding equipment.
[59 FR 40672, Aug. 9, 1994; 59 FR 51672, Oct. 12, 1994; 79 FR 20633-20659, July 10, 2014; 79 FR 56960, September 24, 2014; 80 FR 60037, October 5, 2015]