The purpose of this article is the practical safeguarding of life and property from electrical hazards, arising from the use of electricity for light, heat, power, radio, signaling and other purposes. It covers the electrical conduits, raceways, conductors, and equipment installed within or on public and private buildings and other premises, including yards, carnivals, parking lots, and industrial substations; also, the conductors that connect the installation to a supply of electricity and other outside materials, equipment and conductors adjacent to the premises. It does not cover installations in mines, ships, or such installations as may be exempt by statute, or the equipment employed by an electric or communication utility in the exercise of its function as a utility and located outdoors or in the buildings used exclusively for that purpose. Neither this article nor any rules or regulations adopted by the board of examiners are to be regarded as a design specification or an instruction manual.