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(a) Supports. Open conductors shall be supported on insulators of sufficient mechanical and dielectric strength for the application.
(Title 24, Part 3, Section 3-710-84(a).)
(b) Vertical Clearances. All conductors of outside wiring shall comply with clearances specified in Rule 37, General Order No. 95, 1981 Edition, Rules for Overhead Electric Line Construction of the California Public Utilities Commission, which is hereby incorporated by reference. The following table for overhead conductors and sign clearances is extracted from Tables 1 and 2A of these rules:
Overhead Conductors 750- Over
Nature of Vertical Clearance 20,000 volts 20,000 volts
1. Above tracks of railroads which
transport freight cars where not operated
contact wires.......................28 feet 34 feet
2. Above tracks of railroads operated by
overhead contact wires 30 feet 34 feet 3.
Above and along thoroughfares in urban areas
and above thoroughfares in rural areas 25 feet 30 feet
4. Above areas (other than thoroughfares)
where it is possible to drive vehicles 25 feet 30 feet
5. Above areas accessible to pedestrians
only............................... 17 feet 25 feet
6. Above structures................. 12 feet 12 feet
7. Vertical clearance above all signs upon
which men can walk................. 12 feet 12 feet
8. Vertical clearance above all signs upon
which men cannot walk...............8 feet 8 feet
9. Vertical clearance under signs.. Prohibited Prohibited
10.Horizontal clearance from signs..... 6 feet 6 feet
(Title 24, Part 3, Section 3-710-85(a).)
(c) Clearance from Buildings. Open high-voltage conductors shall be substantially supported independently of buildings or structures and shall have a clearance from buildings or structures as follows:
(1) They shall be maintained not less than 6 feet horizontally from buildings or other structures or any portion thereof. Where the vertical distance above ground of conductors of 7,500 volts or less is in excess of 35 feet, this horizontal clearance from buildings shall be permitted to be less than 6 feet, but shall be not less than 4 feet.
(2) They shall be kept not less than 12 feet vertically above any part of buildings or structures over which they pass.
(3) High-voltage conductors shall be permitted to be attached to a building at only one point, and shall be suitably guarded against accidental contact. There shall be not more than 3 feet of open conductor between the point of attachment and the point where the conductor enters the conduit or is connected to a bushing.
(4) A conspicuous and permanent "HIGH VOLTAGE" sign shall be placed on the outside at the point where a high-voltage conductor enters the building. Where the conductors are not in conduit, a similar sign shall be placed on the inside of the building also, at the point of entrance.
(Title 24, Part 3, Section 3-710-85(b).)
NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code; and Section 18943(c), Health and Safety Code.
1. Editorial correction filed 11-2-83 (Register 83, No. 45).
2. Amendment of subsections (b) and (c) filed 12-10-87; operative 1-9-88 (Register 88, No. 1).
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