The National Electrical Safety Code is a referenced standard to OSHA 29 CFR 1910.269. A referenced standard means it is a voluntary consensus standard that OSHA recognizes as a means to help the employer meet the requirements of the OSHA rules. OSHA will not cite an employer on the basis of an NESC provision, but the agency may use the NESC as evidence the employer knew a hazard existed and may have been prevented using the provisions of the NESC.
The 2017 edition of the NESC was released earlier this year. It has been reorganized for easier use and includes a number of changes and exceptions to rules, as well as the introduction of some new, useful tools to help users more easily access and utilize NESC content. The latest edition follows a tradition to ensure the continued practical safeguarding of persons and utility facilities during the installation, operation and maintenance of electric supply and communication facilities. NESC Part 4 is the pertinent section for lineworker safety, and it has been revised fairly extensively. The following summary of the changes can be a useful guide for those directly impacted in their daily work.
NESC Part 4 rules include a section on arc hazards that was updated in the 2012 edition. At that time, a new low-voltage arc flash table was added that coincides with the rules in the code related to arc hazard analysis. This table has been further modified in the 2017 edition of the NESC. The table, numbered 410-1, is based on recent industry testing performed with the Electric Power Research Institute and Pacific Gas and Electric Co., and now includes more detailed information, primarily on 480-volt arcs.
Revisions have also been made to Rule 410A3 to help ensure that employers perform an assessment to determine the potential exposure to electric arcs for their employees when they go to work on energized lines or equipment. This rule is used to help determine the flame-resistant and other types of personal protective equipment that is necessary. Exception 4 has been added to the rule to help employers and employees understand when protection is needed for the head and face.