With the addition of the installation requirements

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With the addition of the installation requirements that allow for NFPA 70E compliance, there is now an integrated set of documents for worker safety. They are NFPA 70E; NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; and the NEC. Now there is guidance for safety, maintenance, and installation. Grounding and bonding After a great deal of debate in the 2005 revision cycle, the Technical Correlating Committee decided to appoint a task group to examine grounding and bonding. This approach was considered a ~big picture" approach, and the 2008 edition implements the recommendations of the task group. ~This was truly a two-cycle effort that took six years to accomplish," Sheehan says. The result is technically accurate and separate definitions for the terms "ground" and "bond." The language is carried through the document. Back in the 2005 revision, it was proposed that the terminology be completely changed. For the 2008 edition, the definitions were revised. The change runs from the definitions section to the index. "When you have a book that's over 100 years old, sometimes these two terms are used synonymously. You say 'grounding' in one place and 'bonding' in another place. What this does is put everything into a technically accurate context. It is correlated throughout the document, yet the impact on the end user is going to be seamless. We did not change the terminology," says Sargent. So, an "equipment grounding conductor" is still an "equipment grounding conductor" although the definition has changed so it more accurately reflects what it does. This proposal benefits new students because the terms are easier to learn and comprehend. The seasoned users of the Code now have a complete definition they can refer to, and the AHJ knows 80 NFPA JOURNAL MAY/JUNE 2007
exactly what to expect when using the terms. Those involved in the two-cycle approach believe it was the right approach. "This is an added benefit to the students of the Code. This will be much easier to comprehend," says Sheehan. It is proposed that the present definition for "bonding" be rewritten to apply generally throughout the NEC and simply describe its purpose and function. The purpose of bonding is to connect two or more conductive objects together to: (1) Ensure the electrical continuity of the fault current path, and (2) Provide the capacity and ability to conduct safely any fault current likely to be imposed, and (3) Minimize potential differences (voltage) between conductive components. The intent of the term bonding is to convey that normally non-current-carrying conductive materials likely to become energized must be electrically connected together and to the supply source in a manner that establishes an effective fault current path. "Normally non-current- carrying conductive materials likely to become energized" include: (1) Conductive materials enclosing electrical conductors or equipment, or (2) Forming part of such equipment, or (3) Other electrically conductive materials and equipment that may present a shock hazard.

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