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Shell of Protection: Arc-Flash PPE Research Update

This article is intended to update the practical research in arc flash while avoiding the specifics of any method. Personal protective equipment (PPE) in the electric arc has been evolving since the early 1990s. With the introduction of safety and health standards of the U.S. Occupational Safety and Health Administration (OSHA) and arc test methods of American Society for Testing and Materials (ASTM) International, the growth of PPE knowledge and the proliferation of PPE for electric arc has grown throughout the world. In 1995, National Fire Protection Association (NFPA) 70E began addressing arc-flash boundaries, and National Electrical Safety Code (NESC) added the safety requirements for electrical safety. Misunderstandings and errors in marketing still abound, but knowledgeable users, manufacturers, and researchers have helped to make materials more comfortable, protective, and available for many more work situations. OSHA 1910.269 in 1994, NESC in 2007, NFPA 70E in 2000, 2004, and 2009, and now Canadian Standards Association (CSA) Z462 have codified the clothing for electric arc. The International Electrotechnical Committee (IEC) standards use the open arc method developed in the United States and Canada and kept current in ASTM and the box method developed in Germany to offer an International Standards Organization (ISO) path for arcflash research. Brazil, Peru, Russia, South Africa, New Zealand, Australia, and, recently, China are codifying laws related to arc-flash PPE, so the international focus is critical. The international method ASTMF1959 is still the ipso facto standard because of its maturity and repeatability. Other methods provide insight to arc phenomena such as plasma and molten metal expulsion. Research continues with the purpose of improving worker protection, but the two characteristics of preventing ignition and melting materials from being used in arc flash and maintaining a shell of protection during the arc are not easily surpassed with other methods.