Mitigating Arc-Flash Exposure

As more and more industries address arc-flash electrical safety concerns, they are discovering the high risk associated with what used to be normal maintenance tasks. In many cases, the excessively high arc-flash incident energies make it necessary that all maintenance must be done with equipment deenergized, which is not always acceptable to the process industries. This article addresses the multiple ways the authors have devised to significantly lower the arc-flash incident energy exposure by new system design and products, retrofits, retrofills, equipment modifications, and alternate protection settings. In most cases, National Fire Protection Association (NFPA) 70E-2009 hazard risk category (HRC) 2 or lower can be obtained. Several real-world examples are discussed.