Current through Register Vol. 54, No. 45, November 9, 2024
Section 39.142 - Mechanical and thermal protection(a) If exposed to mechanical injury, suitable casing, armor, or other means shall be employed to prevent injury or disturbances to conductors, their insulation, or supports.(b) If conductors with insulating coverings are closely grouped, as sometimes on the rear of switchboards or in cableways, they shall have a substantial flameproof outer covering.(c) Large uninsulated conductors liable to be torn from their supports by the stresses to which they are subjected, as by the magnetic fields produced, shall be so supported that they may not come in contact with the surfaces along which they are run or with other conductors.