Section 408.14008. Electric power and lighting circuits.

Rule 4008. (1) Load-rated switches, circuit breakers, or other devices specifically designed as disconnecting means shall be used for the opening, reversing, or closing of circuits under load conditions. Cable connectors that are not of the load-break type, fuses, terminal lugs, and cable splice connections shall not be used for such purposes, except in an emergency.

(2)   After a circuit is de-energized by a circuit protective device, the circuit shall not be manually reenergized until it has been determined that the equipment and circuit can be safely energized. The repetitive manual reclosing of circuit breakers or the reenergizing of circuits through replaced fuses is prohibited. When it can be determined from the design of the circuit and the overcurrent devices involved that the automatic operation of a device was caused by an overload rather than a fault condition, an examination of the circuit or connected equipment is not needed before the circuit is reenergized.

(3)   Overcurrent protection of circuits and conductors shall not be modified, even on a temporary basis, beyond that permitted pursuant to the provisions of General Industry Safety Standard Part 39 “Design Safety Standards for Electrical Systems,” as referenced in R 408.14001a, which are the installation safety requirements for overcurrent protection.

(4)     Only a qualified person shall perform testing work on electric circuits or equipment.

(5)    Test instruments and equipment and all associated test leads, cables, power cords, probes, and connectors shall be visually inspected for external defects and damage before the instruments and equipment are used. If there is a defect or evidence of damage that might expose an employee to injury, the defective or damaged item shall be removed from service, and an employee shall not use the item until necessary repairs and tests to render the equipment safe have been made.

(6)    Test instruments and equipment and their accessories shall be rated for the circuits and equipment to which they will be connected and shall be designed for the environment in which they will be used.

(7)    Where flammable materials are present only occasionally, electric equipment that is capable of igniting the materials shall not be used, unless measures are taken to prevent hazardous conditions from developing. Such materials include flammable gases, vapors, or liquids, combustible dust, and ignitable fibers or flyings. Electrical installation requirements for locations where flammable materials are present on a regular basis are contained in the provisions of General Industry Safety Standard Part 39 “Design Safety Standards for Electrical Systems,” as referenced in R 408.14001a.

History: 1992 AACS; 2015 AACS.