Arc Flash Hazard Analysis

An arc flash is a sudden release of heat and energy caused by an electric arc. The explosion is commonly triggered by equipment failure, switching, sparks, corrosion, condensation, dust or other impurities on the surface of a conductor. Arc flash explosions are unpredictable, dangerous and occur daily in electrical equipment across the U.S., they can lead to serious injury, equipment damage, lost production, downtime and fines. RLC’s team of experienced Electrical Engineers can help you, calculate your risk, address NFPA 70E electrical safety compliance issues and identify arc flash hazards in your facility.

The RLC Engineering Arc Flash Analysis Program is one of the most comprehensive in the industry, taking a full service approach from data collection to generation of equipment warning labels. Our combination of experience, quality and dependability has made RLC Engineering one of the most trusted resources in the electric utility and renewable generation engineering fields.

Data Collection

The first phase is the collection of field data necessary to calculate potential incident energy at power distribution equipment. Phase I is the labor intensive phase of the arc flash hazard study, typically taking at least half of the total effort required to complete the analysis. Data is collected on-site by qualified persons (as defined by OSHA and NFPA 70E) in appropriate PPE; preferably assisted by a qualified facility employee or someone knowledgeable of the plant electrical equipment and facility layout.

Data collected for the study includes transformer nameplates, conductor sizes/number per phase/lengths, motors larger than 50HP, circuit breaker catalog numbers and settings, fuse catalog numbers, and on-site generator nameplates. Generally all the data can be collected without disturbing facility operations. Proper labeling of each disconnect as to its purpose (in accordance with NEC® 110.22), is required in order to complete an accurate analysis.

Generally, the electric utility will be contacted to determine the short circuit current available at the facility’s metering point.

Power System Modeling / Electrical One-Line Diagram Development

A power system model of the facility is created using the electrical one-line diagram developed from the data collection. Electrical elements and components are shown by standard industry accepted symbols representing each of the three phases and the connection of the power system with one line. The diagram represents the actual facility power distribution system and path from the incoming power source to all loads and equipment.  RLC Engineering is proficient in many arc flash analysis power system software platforms to include SKM Power Tools for Windows, EasyPower®, ArcPro, Aspen, and CYME.

Engineering Calculations & Hazard Analysis / Study

This phase is completed and / or reviewed by a licensed professional electrical engineer knowledgeable in the use of electrical engineering software, IEEE 1584 and NFPA 70E.  The power system analysis software is used to determine the following:

  • Short Circuit Study
  • Device Interrupt Rating and Evaluation Study
  • Selective Coordination Evaluation of Protection Devices
  • Arc Flash Hazard Study Analysis
  • Recommended Solutions to Problems and Identify Opportunities
  • Written Analysis Report

Reporting of Results

A comprehensive report of the results of the engineering studies completed includes references to OSHA and NFPA requirements, in depth descriptions of parameters that effect the incident energy of equipment, safety guidance for implementing arc flash safety, and the recommended solutions for improving the electrical distribution system. This report is accompanied by the system model of the facility, short circuit results, and protection device coordination plots.

Labels & Label Application

Each piece of equipment analyzed will have a printed label compliant to NFPA and NEC. Labels include shock hazard assessment and warning to meet NFPA requirements.

Arc Flash

RLC’s staff of licensed electrical engineers have extensive experience in the design and analysis of power distribution systems for Utility and Power Generation facilities.

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Questions about Arc Flash Hazard Analysis?

Contact Jon Gay, PE

207-621-1077, x134