The provisions of this recommended practice apply to (a) All electrical equipment and wiring between the point of connection in the power supply substation and the connection to the furnace or forehearth electrodes for the purpose of heating the glass by the passing of electric current through it. (2) All electrical equipment and wiring that is connected directly to resistance heating devices that supply energy to the furnace of forehearth. (3) All sensors and devices used to measure, alarm, or regulate energy, mass flow, and temperature. (4) The adequate electrical insulation from ground of the refractories containg the molten glass. (5) The adequate electrical grounding og equipment and services. (6) All equipment and procedures pertaining to safeguarding personnel.