A glimpse of the proposed changes for the 2012 edition of NFPA 70E
NFPA Journal, May/June 2010
The world of workplace electrical safety is rapidly evolving, in large part due to the increased awareness and implementation of NFPA 70E®, Electrical Safety in the Workplace®, in the last decade. The confluence of new developments in personal protective equipment (PPE), electrical equipment and system design, and new research has resulted in significant progress toward understanding and addressing electrical hazards.
To keep pace with these developments, a number of important revisions have been proposed for the 2012 edition of NFPA 70E, changes designed to provide not just new information but improved user interface and implementation, as well.
Proposed changes accepted in the Report on Proposals (ROP) include adding columns to the hazard/risk category classifications table to provide the maximum available short-circuit current and overcurrent protective device clearing time parameters for every task associated with all equipment currently covered, including equipment rated over 600 volts. A column with the arc flash boundary for every task has also been added. Many users of NFPA 70E rely daily on these task and PPE tables to protect themselves and their employees against electric shock and arc flash injuries.
To clarify what the committee considers vital user information, it has proposed revising the requirement for equipment labeling to be more specific as to what is currently required and to expand the required content. The committee has also identified the types of equipment and the conditions of use that trigger the application of the labels. The proposed revision specifies that “switchboards, panel boards, industrial control panels, meter socket enclosures, and motor control centers that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field-marked with a label containing all the following information….” The required information includes either the available incident energy or the minimum arc rating of protective clothing (but not both), as well as the date of the arc flash hazard analysis, the nominal system voltage, and the arc flash boundary.
Users of NFPA 70E commonly ask if it applies to direct current (dc) systems. Nowhere does the standard specify that it applies only to alternating current (ac) systems, and OSHA does not exclude dc hazards from workplace safety requirements. While many NFPA 70E requirements are based on ac systems because of their predominant use, the purpose of the standard does not indicate that it is to only provide a safe working area for employees exposed to ac hazards. Electricity includes ac and dc systems, and there are hazards associated with both.
It is interesting to note that, in many circles, the same issue exists for NFPA 70®, National Electrical Code® (NEC®). Many NEC requirements are specific to dc systems.
Based on committee actions related to proposals specific to dc systems, the 2012 edition of NFPA 70E will clearly address the hazards associated with such systems. Included in the accepted committee actions on dc system safety requirements are actions to add a dc approach boundary table similar to current Table 130.2(C) and a dc task table similar to current Table 130.7(C)(9).
The first step in processing the 2012 edition of NFPA 70E has been completed; the ROP and a draft of the proposed revisions will be available at www.nfpa.org/70E on or about June 25. Public comments on the committee’s proposed actions are due September 3.
Jeffrey Sargent is NFPA's senior electrical specilist and is staff liason for NFPA 70E.