(a) Installations and inspections. All electrical equipment installations shall be approved and all electrical inspections made by a qualified person.

(b) Grounding.

(1) Where grounding wires are used to ground metallic sheaths, armors, conduits, frames, casings, and other metallic enclosures, such grounding wires will be approved if:

a. The cross-sectional area (size) of the grounding wire is at least one-half the cross-sectional area (size) of the power conductor where the power conductor used is No. 6 A.W.G. or larger.

b. Where the power conductor used is less than No. 6 A.W.G., the cross-sectional area (size) of the grounding wire is equal to the cross-sectional area (size) of the power conductor.

(2) The protective grounding of electrical circuits and equipment to water pipe systems, when available, is desired as such grounding offers the most effective protection to life and property. Gas or air pipelines shall not be used for grounding circuits. Metal well casings, metal drain pipes, and similar buried metal structures of considerable extent may be used in lieu of extended buried water piping systems.

(3) The ground connection to metallic piping systems shall be made by means of a suitable connection firmly attached to the pipe after all rust and scale have been removed, or by means of a brass plug which has been tightly screwed into a pipe fitting or, where the pipe is of sufficient thickness, screwed into a hole in the pipe itself or by other equivalent means. The grounding conductor shall be attached to the clamp or to the plug by means of solder or a suitable solderless connector.

(4) If conduit, couplings, or fittings having protective coatings of nonconducting material, such as enamel, are used, such coating shall be thoroughly removed from couplings, conduits, and such surfaces of fittings where the conduit or ground connection is secured in order to obtain a good connection.

(5) Artificial grounds should be located where practicable below permanent moisture level, or, failing in this, a suitable means of grounding shall be used.

(6) Where copper ground plates are used, they should be at least six hundredths of an inch thick. When driven pipes are used, they should be of galvanized iron and not smaller than three fourths of an inch internal diameter, and when cast iron plates are used they should be at least twenty-five hundredths of an inch thick.

(c) Insulation.

(1) All fixed electric light and power lines, regardless of voltage, shall be properly supported on standard insulators.

(2) Drop cord extension light lines shall be flexible with heavy rubber insulation, equipped with a heavy wire light globe shield, hook, and heavy rubber handle.

(d) Trailing cables.

(1) Where employees are required to handle energized high voltage trailing cables, they shall be required to use cable tongs and wear rubber gloves. Where surroundings are wet, such employees shall also be required to wear rubber boots.

(2) Damage to the insulation of trailing cables shall be promptly reported and repairs made. Splicing shall be done only by a competent electrician or person competent to splice cables, and splices shall be made moisture-proof. Where it is necessary for mechanical equipment to cross a cable, safe cable bridges shall be provided and used. Where armored cables or conduit are used, the armor or metal conduit shall be electrically continuous, and, when necessary to splice armored cable, the broken section of the armor shall be bonded to insure electrical continuity.