POWER DANGERS

Wairarapa Times-Age, 24 December 1938, Page 3

POWER DANGERS

IMPORTANCE OF EARTH WIRES. Provisions of safety REGULATIONS. One of the most important, and yet, to the average layman, one of the most perplexing matters about an electrical installation is the earthing system, applied to the various domestic and commercial appliances in everyday use. A fault in an appliance can and has been known to cause fatal electric shock because of damage to, or a fault in, the earthing system of the electrical installation from which the appliance has been operating.

In recent reports by electrical supply authorities it was stated that, during the reinspection of electrical installations, it was found in a large number of cases that the main earth wire had been interfered with in the course of building or plumbing alterations, and in some cases the earth pipe had been covered over with concrete.

When appliances are properly earthed on an installation, in which similar precautions have been taken, there can be no danger from electric shock, because, if a fault occurs, such as a frayed live wire coming in contact with metal parts of the appliance, sufficient current will pass through the installation to blow a fuse. If, however, the earth system is defective it is possible for a person operating a faulty appliance to complete the circuit to earth through the body, and thus receive the full force of the electric power in the installation. The Public Works Department and the Electrical Wiremen’s Registration Board have given a lot of consideration to this matter, and, after consultation with the power supply authorities throughout the Dominion the board recently issued a circular on the subject. The safety regulations require that all earth wires shall be protected against mechanical injury and shall be run, as far as possible, in a manner which will avoid the risk of interference. Where the earth wire is fixed to the outside of a building, the mechanical protection should extend to a distance of not less than six feet above ground. It is essential, the circular states, to remember that in all premises where building work is being done, any work upon earth wires, or affecting them, is required by law to be done by a registered wireman.

Chief: “You are an hour late.” Clerk: “Yes, sir. I fell down a flight of stairs,” Chief: “But surely it doesn’t take an hour to fall down a flight of stairs?”