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In keeping with the stated purpose of the National Electrical Code (NEC), the “practical safeguarding of persons and property…” protecting workers from electrical shock while using temporary power is of great concern for all electrical contractors. Article 305 of the NEC, “Temporary Wiring,” contains very specific protective requirements.
Over the past several Code cycles, increasing restrictions have been placed on the use of the assured equipment grounding conductor program (AEGCP). This article reviews and discusses the development of the program in Article 305, a proposed restriction for the 2002 NEC, and how this proposal affects worker protection. Background The 1999 NEC, Section 305-6 requires in part that “(A)ll 125-volt, single-phase, 15-, 20-, and 30-ampere receptacle outlets that are not a part of the permanent wiring of the building or structure and that are in use by personnel shall have ground-fault circuit interrupter protection for personnel.” This section has received considerable attention through the past several Code cycles. There have been three significant changes. First, in the 1996 NEC, the section was revised to significantly expand the scope of the requirement beyond construction sites. Prior to 1996, Section 305-6 requirements were applicable only to “construction sites.” By deleting this reference, the scope was expanded to include maintenance, remodeling, demolition, repair, and similar construction activities. Second, the permission to use the AEGCP as an option to replace ground-fault circuit interrupter (GFCI) protection was essentially removed. As noted above, if temporary power is supplied from a 15-, 20-, or 30-ampere (1999 NEC), 125-volt receptacle outlet, GFCI protection is the only option. Over the past several Code cycles, Code-Making Panel 3 (CMP-3) has clarified that many forms of GFCI protection, including cord sets or devices incorporating listed ground-fault circuit interrupter protection for personnel identified for portable use, are permitted methods to provide the necessary protection. Finally, when the 1996 NEC expanded the scope of the section, an exception was added for industrial establishments. This exception was revised in the 1999 NEC to clarify that it applies to all receptacle outlets. “In industrial establishments only, where conditions of maintenance and supervision ensure that only qualified personnel are involved, an assured equipment grounding conductor program as specified in Section 305-6(b)(2) shall be permitted to be utilized for all receptacle outlets.” The effect of this exception was to remove the prohibition of the AEGCP by permitting industry, under certain conditions, to continue to use the program.
2002 proposed revision
Consistent with the trend that CMP-3 has followed, the Panel developed a proposal for the 2002 NEC, which will delete the current exception cited above, for industrial establishments. The Panel noted that the “sufficient availability of GFCI Protection and proven safety record eliminates the need for this exception.” What is of significant interest is that the action on this proposal resulted from a public proposal which sought to restore the 1996 requirements. The proposal would have deleted the words “in industrial establishments only.” The net effect would have been to permit the AEGCP to be used wherever the “conditions of maintenance and supervision ensure that only qualified personnel are involved,” for all receptacle outlets. The Panel statement, in rejecting this proposal, confirmed once again that “GFCI protection affords a higher level of protection for all workers” and should be the preferred choice. The Panel statement goes on to read, “[Occupational Safety and Health Administration] OSHA inspection & citation data clearly indicates the many problems associated with the lack of implementation of the AEGCP.” Based upon this review of the record, CMP-3 generated a Panel proposal to delete the exception. Analysis Interestingly, the original proposal in 1996 attempted to delete all references to the AEGCP. Industry strongly objected, a compromise was made, and the program survived, although its application was severely limited. The substantiation for the 2002 proposal to restore the AEGCP to where it stood before the 1996 revisions states that, “(A)ny user capable of implementing the program should be permitted to use it.” Unfortunately, as OSHA data supports, the program is frequently not implemented properly and this results in worker exposure to electrical hazards. The AEGCP involves several key steps for proper implementation.
1) All equipment grounding conductors shall be tested for continuity and shall be electrically continuous.
2) Each receptacle and attachment plug shall be tested for correct attachment of the equipment grounding conductor. The equipment grounding conductor shall be connected to its proper terminal.
3) All required tests shall be performed a) Before first use on site, b) When there is evidence of damage, c) Before equipment is returned to service following any repairs, and d) At intervals not exceeding three months.
Think about how complex and comprehensive this program would need to be on a multi-employer construction site with a dynamic workforce comprising of many sub-contractors. And, even if these steps are fully implemented, the result is a level of protection inferior to that provided by GFCI. In the end, electrical contractors can meet both NEC and OSHA requirements. By using GFCI protection for their employees, they can provide a superior level of protection from electrical shock, and they can do so in a manner that is less costly than the AEGCP.
In summary, the proposal to delete “in industrial establishments” would have been, as one panel member stated, “a major step backwards for worker safety.” CMP-3 should be credited with taking a bold step to enhance worker safety. Perhaps unknowingly, but nevertheless, CMP-3 has crossed the line by deleting one of the many exceptions for “industrial establishments” that have crept into our Code at an alarming rate. Has the issue of the efficacy of the AEGCP finally come full circle? The 2002 cycle is not yet complete, but if this panel proposal stands––as it well should––workers can be assured that wherever they work, in industrial, commercial, or residential establishments, they will be given the very best possible level of protection from electrical shock.
CALLANAN is director of Safety, Codes, & Standards at the National Joint Apprenticeship & Training Committee. He can be reached at [email protected].