Arc Flash Analysis

"Flash Hazard Analysis shall be done before a person approaches any exposed electrical conductor or cicuitpart that has not been placed in an electrically safe work condition."
-NFPA 70E-50 Part II 2-1.3.3

• Arc flashes are caused by either a phase to ground or phase to phase fault; they are instantaneous and can result in severe employee injury or death.
• Temperatures from the arc-plasma fireball caused by exploding electical equipment may exceed 35,000°F (the surface of the sun is 9000°F).
• Sound levels of 141.5 decibels at 2 feet from the blast and pressure levels of 2,160 pounds per square foot (psf) in the immediate vicinity of the blast have been detected in an arc flash.
• 5 to 10 severe arc flash explosions occur daily in the US requiring treatment from a special burn unit.
• About 80% of all electrical injuries are burns resulting from the electric arc flash and ignition of an employees' flammable clothing.
• Each incident could result in more than $15 million in direct and indirect costs to a company.

Facility owners, along with safety and maintenance personnel, should also be aware that four industry standards and regulations have established procedures for preventing arc flash incidents and ensuring employee safety. Compliance with the following is being carefully monitored by OSHA:

• OSHA 29 Code of Federal Regulations (CFR) Part 1910, Subpart S: states that electrical safety practices and appropriate protective equipment be employed to prevent employee injuries.
• NEC 2002, Section 110.16: requires that visible warning labels are placed on equipment likely to cause arc flash conditions.
• NFPA 70E-2000, Standard for Electrical Safety Requirements for Employee Workplaces: requires employers to determine if electrical hazards are present, and have each employee use the proper types of Personal Protective Equipment that will protect them. Also provides the detailed actions companies must take to be in federal compliance.
• IEEE Standard 1584-2002, Guide for Arc Flash Hazard Analysis: establishes nine steps used in the arc flash analysis process.

PENTA Engineering's experienced Professional Engineers are positioned to perform a complete analysis of your electrical distribution system so that the proper preventive measures can be taken based on these prevailing standards and regulations. Performing an Arc Flash Analysis per IEEE 1584 or NFPA 70E standards requires, as a minimum, the following activities:

• Short Circuit Study
• Over-Current Coordination Study
• Equipment Evaluation

Upon completion of the analysis, PENTA provides a report that lists each piece of electrical equipment, its corresponding Arc Flash and Shock Hazard Rating and the required protective personal equipment. For each piece of electrical equipment, there are two options: accept the Rating or modify some internal components and reduce the Hazard Rating. Lastly, the appropriate warning labels must be placed on each piece of equipment.

In addition to performing the Arc Flash Analysis, our Engineers can provide:

• Protective Personal Equipment (PPE) Specification
• Recommendations for electrical system modifications to reduce arc flash hazards
• Electrical system documentation in AutoCAD or Microstation
• Electrical equipment labeling to comply with NEC 110.16 labeling requirement.

Taking the appropriate action can help reduce workplace injuries and deaths, prevent equipment damage, and increase uptime for any company.