SIDEBAR: NFPA 70E — Spotlight on Protection
Part 4 of a 4-part article on arc flash safety
The standard NFPA 70E, Electrical Safety Requirements for Employee Workplaces now includes revised detailed tables for arc-flash hazard identification and personal protective equipment (PPE) categories in the 2015 edition. The standard’s tables outline specific levels of PPE for various types and ratings of electrical equipment.
Special PPE might not be necessary for certain tasks where the risk of an arc flash or shock hazard are low, such as normal operation of properly installed and maintained equipment. As specified in NFPA 70E, the following criteria govern the use of the table method for assigning PPE:
- The task must be listed in tables.
- The power system applied is less than the estimated maximum short circuit current used for tables.
- The power system applied is shorter than the clearing times used for tables.
- The tasks are greater than or equal to the minimum working distances listed in the table.
The new 2015 NFPA 70E table replaced the term “hazard risk category” with the term “PPE category.” Managers also should note that the 2015 PPE table has changed from the 2012 table by eliminating the PPE category (hazard risk category) of 0, which does not require the use of PPE. In addition, the PPE category tables have been expanded into three tables: a table to determine whether arc-flash PPE is required, a table to determine the arc-flash PPE category, and a table that lists the clothing and PPE required for that category.
Another option for selecting PPE is to use the Incident Energy Analysis Method. To use this method, a facility must have completed an incident energy analysis as part of an arc flash risk assessment — formerly an arc flash hazard analysis — to determine the incident energy, measured in calories per square centimeter. If an incident energy analysis has not been completed, managers should refer to the 2015 Edition of NFPA 70E for the category table selection method discussed above.