R 408.41725 Wiring; attachment plug receptacles; extension and trailing cords; handlamps; portable electric tools used in wet environment; convertor supplying equipment at more than 300 volts.

Rule 1725. (1) When electrical wiring is used in a tank or other confined space, a properly identified disconnect switch shall be provided at the entrance. (2) A receptacle for an attachment plug shall meet all of the following requirements: (a) Be of the concealed contact type. (b) Have a contact for extending ground continuity. (c) Be designed and constructed so that the plug may be removed without leaving any live parts exposed to contact. (d) Not be capable of receiving attachment plugs for a voltage, frequency, or type of current different from that for which the receptacle is intended, nor shall a plug of a different style be forced into a receptacle. (3) An extension cord used with a portable electric tool or appliance shall be a 3-wire type. (4) Conductors supplying temporary wiring shall be the minimum protective qualities of type NM wire for use indoors, or type UF wire for use outdoors. (5) A brass shell, paper lined lamp holder and a pintype lampholder which damages the insulation shall not be used. (6) Wiring for temporary lighting in excess of 12 volts used on barricades, fences, and sidewalk coverings shall be protected against abrasion of accidental damage to the insulation. (7) Trailing cords and extension cords shall meet all of the following: (a) Be protected against damage. (b) Hung in a manner which does not damage the covering. (c) Retain their insulating value and dielectric and physical strength when spliced. (d) Be insulated to prevent shock or shorts. (e) Have a plug body or receptacle which is either molded to the cord or is equipped with a cord clamp to prevent strain on the terminal screws, or a receptacle installed in a steel box with a cover and cord clamp. (8) A portable handlamp shall be made of molded composition or other approved material and shall have a molded handle with bulb guard attached to it. (9) A portable light used in moist or other hazardous areas, such a drum, tank, or vessel, shall be operated at a maximum of 12 volts, or shall be protected by an approved ground-fault interrupter. (10) A portable electric tool used in a wet atmosphere or environment shall be protected by an approved ground-fault interrupter. (11) An attachment plug or other connector supplying equipment at more than 300 volts shall be of the skirted type or shall be otherwise designed to confine any arcs.