Arc Flash Analysis

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Arc flash analysis begins with a meeting to understand your mode of operation. We offer assistance and guidance for the required survey of onsite equipment and its ratings necessary for a comprehensive arc flash analysis. We work with you to establish the appropriate working distances for the analysis, and provide recommendations for arc flash mitigation measures to help reduce the incident energy levels and the resulting hazard risk category. Finally, a comprehensive report and appropriate arc flash labels for equipment are provided as a result of the studies and mitigation measures adopted.

Of course, it is important to understand that arc flash evaluation is only valid for the conditions at the time of the study; we caution our clients to be aware of modifications to their systems, protective device settings, and utility sources and the impact those modifications may have on their hazard levels. Per NFPA 70E, we recommend periodic review of arc flash hazard levels.

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Exponential Engineering runs various comprehensive computer based software packages to:

  • Perform a fault study and determine the bolted fault currents for the various system operating modes.
  • Determine the arc fault current.
  • Find the protective device characteristics and duration of the arc.
  • Document system voltages and classes of equipment.
  • Select the appropriate working distance.
  • Determine the incident energy for all equipment in the study.
  • Determine the flash-protection boundary for all equipment in the study.

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Applicable Standards used to perform an arc flash study are:

  • OSHA CFR 39 Part 1910 Subpart S
  • National Electric Code (NFPA 70 - 2008) Section 110.116
  • Standard for Electrical Safety in the Work Place (NFPA 70E - 2009)
  • IEEE Guide for Performing Arc-Flash Analysis Calculations (EEE Std. 1584 – 2002 w/ 2004 Amendment)
  • National Electric Safety Code (IEEE Std C2 – 2007)