Table 7-2. AC live-line work minimum approach distance

DOE-HDBK-1092-98

Table 7-2. AC live-line work minimum approach distance.

Distance, Phase to Employee

Phase to Phase

Phase to Ground Exposure

Phase to Phase Exposure

Nominal Voltage (kV)

(ft - in)

1 or less

Avoid contact

1.1 to 15

2-1

2-2

15.1 to 36

2-4

2-7

36.1 to 46

2-7

2 - 10

46.1 to 72.5

3-0

3-6

72.6 to 121

3-2

4-3

138

to 145

3-7

4 - 11

161

to 169

4-0

5-8

230

to 242

5-3

7-6

345

to 362

8-6

12 - 6

500

to 550

11 - 3

18 - 1

765

to 800

14 - 11

26 - 0

Note 1: These distances take into consideration the highest switching surge an employee will be exposed

to on any system with air as the insulating medium and the maximum voltage shown.

Note 2: The clear live line tool distances shall equal or exceed the values for the indicated voltage ranges.

Note 3: See 29 CFR 1910.269, Appendix B for information on how the minimum approach distances

were derived.

7.5.3 GROUNDING EQUIPMENT

The American Society for Testing and Materials (ASTM) Committee F-18, "Electrical Protective

Equipment for Workers," has developed and published a consensus standard for protective grounds,

ASTM Designation: F-855. In accordance with Office of Management and Budget (OMB) Circular

No. A-119. October 27, 1982, this voluntary consensus standard may be used by all Federal agencies

for procurement purposes. Therefore, grounding cables, clamps, and ferrules purchased should meet

all the requirements of ASTM Designation: F-855. Aluminum cables shall not be used for personal

grounds.

The grounding of high-voltage lines and equipment will provide workers with additional protection

from electric shock if grounds are sized, selected, and installed properly. For further information on

the construction of personnel protective grounds, see ASTM F855-90.

7.5.3.1 AVAILABILITY

Grounding cables shall be available for use when work is being done on deenergized lines or

equipment.

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