arc flash definition
The arc causes an ionization of. the air, and arc flash. temperatures can reach as high. as 35,000 degrees Fahrenheit. This is hotter than the surface. of the sun”. eardrums to rupture resulting in temporary or permanent hearing loss. Molten metal can be sprayed by the blast throughout the vicinity. The NFPA 70E Standard details multiple levels of Hazard Risk Categories (HRC) [see table 1.1], also called Levels. The greater the risk: the higher the HRC. Arc Rating is the factor that indicates which HRC is necessary, and can be measured in either ATPV or EBT. Part of the Data center management glossary: An arc flash is an undesired electric discharge that travels through the air between conductors or from a conductor to a ground. The resulting explosion can cause fires and serious harm to equipment and people. Damage is caused both by the explosion of the arc flash and by the heat radiating from the blast. It is possible to protect against arc flash with the proper protective equipment and, more importantly, safety procedures and training. The IEEE has created a set arc flash standards that companies can use during facilities planning to help minimize the risk of arc flash in the first place. Your best source for complete information on the NFPA 70E Standard is via the actual standard, available for purchase at www.nfpa.org. In 2000, the NFPA 70E Standard first addressed electric arc flash hazard and required flame resistant arc flash clothing to protect workers. The current edition of the NFPA 70E standard was released in 2012, and further details personal protective equipment. The Arc Flash can be initiated through accidental contact, equipment which is underrated for the available short circuit. current, contamination or tracking over insulated surfaces, deterioration or corrosion of equipment and, or parts, as well. as other causes. An arc flash hazard exists if a person is or might be exposed to a significant thermal hazard. If the thermal hazard is of a severity that might expose a person to 1.2 calories per square centimeter. (cal/cm2) or more of incident (thermal) energy, the hazard is considered to be significant. Incident Energy Analysis. A component of an arc flash hazard analysis used to predict the incident energy of an arc flash risk assessment for a specified set of conditions. An incident energy analysis is an important part of performing the arc flash hazard analysis for a specific task and item of electrical equipment. The definitions are imperative to know as we use these terms explaining the Arc Flash Risk Assessment and the NFPA 70E. These definitions have been gathered from the 2015 Edition NFPA 70E. The goal of NFPA 70E is to protect electrical workers around any device capable of generating arc flash, and provides recommended safety practices for industries involved in the installation, repair and maintenance of electrical systems.
It is an undesired electric discharge that travels through the air between conductors or from a conductor to a ground.