Components of an arc flash hazard risk management program represent a typical sequence of tasks conducted by the system owner, or in conjunction with a third-party service provider, to implement a personnel safety and system reliability solution.
The process starts with a commitment by the system owner to define, document, and implement safe operating practices. This should include electrical safety and policy procedures. Many of these procedures are defined in the NFPA 70E standard as it relates to electrical safety in the workplace.
Specific locations with electrical infrastructure where hazards may be present need to be identified. Details of the electrical system layout are required as the basis to define a scope of work for a risk management solution.
The user or third-party service provider will verify system data on-site. This data will be used to model an electrical representation of the system in order to perform a short circuit, coordination, and arc flash analysis. The analysis is performed according to industry standards using one of several available software applications.
A knowledgeable professional systems engineer will use the tools in the application software to calculate available fault current and recommend protective device settings that optimize system operation while minimizing the magnitude of the arc flash hazard at equipment locations where work may be performed while systems are energized.
A report is provided to document the results of the study by device, including actions to replace underrated devices that can no longer safely interrupt the available fault current and relay settings to support the approved recommendations of the study.
Once the results of the study are approved by the user, equipment labels are produced that provide all of the necessary information workers will require to wear appropriate PPE and define safe working distances. These labels are then available for installation on the electrical devices as defined in the study.
An arc flash analysis documents and analyzes a user’s existing system for what it is. It could be a relatively new, state-of-the-art electrical system with the latest gear, a decades-old system with equipment that is no longer manufactured, or something in between. As a result, there are situations where the ability to reduce the magnitude of arc flash hazards while also providing desired protection device coordination for optimal system operations has its limits.
For example, reducing the magnitude of the hazard to a level where PPE is available to work with energized equipment, or that allows the use of more comfortable PPE work clothing in lieu of an arc flash suit. In those cases, an engineered solution, including equipment changes or modifications, may address some of these limitations.
Finally, an arc flash analysis is essentially a snapshot in time. It documents the user’s electrical system as currently configured. Any changes to the system could invalidate all or a portion of the results provided in the study report. Accordingly, NFPA 70E requires the study to be rerun a minimum of every five years or when major changes have been made to the system. Periodic updates not only keep the study current to retain the benefits of safety and system reliability but, in the long run, make the ongoing implementation of an arc flash safety program less costly and complex.
Qualified field personnel to perform on-site tasks for single or multiple locations, including data collection, labeling, relay settings, breaker testing, device replacement, and installation of an engineered solution.
Professional engineers to perform system analysis, review results, and provide supporting documentation
Comprehensive training program to educate and measure understanding of safety procedures.
Application engineering capability to develop and implement additional mitigation solutions.
Data center project experience for single- and multi-site implementation.
A process to manage system changes that support ongoing personnel safety and system reliability
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