May 2018

Arc Flash Hazards and Risk Assessment

The 2018 update of NFPA 70E®, Standard for Electrical Safety in the Workplace®, was released late last year. It is meant to eliminate unacceptable risk associated with the use of electricity in the workplace, and specifies the requirements for electrical safety plan development, implementation, and maintenance.

>According to the standard, there are six primary responsibilities that facilities must meet. These include:

  • Training for employees
  • Written safety program in place that is actionable
  • Personal Protective Equipment (PPE) available for employees
  • Insulated tools
  • Arc flash hazard degree calculations
  • Properly labeled equipment

Risk Assessment

Article 130 of the NFPA 70E standard specifically addresses work involving electrical hazards; any work that requires an electrically safe work condition; and any work involving safety-related work practices, assessments, precautions, and procedures when an electrically safe work condition cannot be established. To quantify the risk present, two assessments must be done for each affected electrical equipment piece – shock risk assessment and arc flash risk assessment. The assessments must identify the hazard; estimate the likelihood and potential severity of injury or damage to health; and determine if additional protective measures are required, including the use of personal protective equipment (PPE).

If likelihood does exist, the appropriate arc flash PPE must be determined by using either the incident energy analysis method or Arc flash PPE category method, but not both. In previous editions of NFPA 70E, the PPE category method utilized a table to help users determine if PPE was required for a given task, but it was not applicable to a risk assessment conducted with the incident energy analysis method. For 2018, that older table has been removed and a modified table now exists – Table 130.5(C). The result is a better tool for all users, whether they’re applying the incident energy analysis method or the PPE category method.

Labels Required

NFPA 70E continues to require equipment owners, not the manufacturer or installer of the equipment, to apply detailed and informative labels to any electrical equipment that is likely to require adjustment or maintenance while energized (creating the potential for an arc flash incident to occur). Labels must include:

  • Nominal system voltage
  • Arc flash boundary
  • At least one of the following:
    1. Available incident energy and corresponding working distance, or
    2. Arc flash PPE category for the equipment as listed in tables in the standard
  • Minimum arc rating of clothing
  • Site-specific level of PPE.

Arc flash and shock hazard warning sign image.
Image Credit: Lewellyn Technology

The recent 2018 update allows labels applied prior to the effective date of this edition of the standard to be acceptable if they complied with the requirements for equipment labeling in the standard in effect at the time the labels were applied (unless changes in electrical distribution system render the label inaccurate).

Facilities must document the method of calculating and the data to support the information for the label and review for accuracy at intervals not to exceed 5 years. The label needs to be updated when the review of the data identifies a change that renders the label inaccurate.

Risk Logic, Inc. hopes to have answered your questions about arc flash hazards, with regard to the recent changes of NFPA 70E.