The 2015 edition of NFPA 70E®, Electrical Safety in the Workplace®, is scheduled for release by the NFPA Standards Council at its meeting in August. Users of the standard eagerly await this new edition, which represents the next step in protecting workers against dangerous shock and arc-flash accidents.
One way to protect workers is through the use of the proper level of personal protective equipment (PPE). Since the 2000 edition of NFPA 70E, one of the methods to determine the appropriate level and use of PPE has been the standard’s hazard/risk category classifications, commonly referred to as the “table method” or “task tables.” As those terms suggest, these tables are task-based and enable workers to easily select the proper level of PPE based on the type of electrical equipment in question, along with the specific parameters associated with the electrical supply and the operation characteristics of the circuit protective device. Thousands of electricians and maintenance personnel have successfully used these tables to select PPE for protection against electrical shock and arc-flash hazards.
The task tables are limited in application based on specific electrical supply system characteristics. Since the tables were first included in the standard, some members of the 70E committee have been concerned that users would fail to recognize these limitations and apply the table method to systems where the arc-flash hazard exceeds the level covered by the tables. Reformatting of the information in the 2015 version addresses this concern by more clearly identifying the specific system parameters and arc-flash boundaries.
To provide a more objective assessment of the arc-flash hazard associated with a specific electrical task, the task tables have undergone some significant changes. First, a new title—“Arc-Flash Hazard Identification for Alternating Current (ac) and Direct Current (dc) Systems”—reflects that the table information is only for use in selecting PPE for arc-flash protection. As part of this remake, the information on the use of rubber insulating gloves and insulated tools for shock protection is no longer specified in this table but is found elsewhere within the document.
Another change is that the tables now cover more dc tasks. Expanding on the inclusion of information covering dc shock and arc-flash protection in the 2012 edition, specific tasks associated with batteries and dc utilization equipment have been added. These additions are needed to keep pace with the rapidly expanding use of dc energy storage, distribution, and utilization equipment.
The third and perhaps most significant change related to the use of the tables is the way that the tasks are presented. Instead of assigning a hazard/risk designation based on the task, type of equipment, and electrical system and protection characteristics, the task table now simply states whether there is an arc-flash hazard with a “yes” or “no.” If the answer is yes, PPE will be required and the category of PPE will be specified in another table based on the type of equipment and the electrical system and protection characteristics. The description of the type of PPE required based on the designated category will be presented in the same format as it was in the 2012 edition with the noticeable deletion of “Category 0.”
These changes simplify the process of assessing risk and determining the proper PPE. In the new edition of the standard, there is either an arc-flash hazard or there isn’t, and if there is, the tables indicate the necessary level of PPE. If the specific task is not covered in the table or if the electrical system limitations are exceeded, the incident energy analysis (calculation) method must be used to determine if PPE is needed and what the appropriate level should be.
Jeffrey Sargent is a regional electrical code specialist for NFPA.