Risk mitigation for telephone operators and technicians

There is a growing concern that telephone operators and equipment technicians may be at lethal risk in certain lightning-related situations. The author explores this potentially dangerous situation and offers several schemes to reduce or eliminate the risk to human life. Operators and technicians would be much safer if the equipment they connect their bodies to is at the same electrical potential as the building they occupy. Input/output terminals or operator service positions could be located within the integrated ground plane to maximize the safety of the workers. There are modems in the marketplace which offer a high degree of electrical isolation. Accordingly, if two modems were installed, one at the terminal and one at the switching system, and a two-wire channel established between them, then the terminal could safely reside in the integrated ground plane. Other means of accomplishing this are isolation-type lines drivers and fiber-optic systems. Modern techniques for circuit board layout, electrostatic shielding, and other physical design criteria could eliminate the need for the isolated ground plane.<
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