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The design of a power system is an assessment in safety and functional performances correctible and perfectible during its life cycle with risk and quality management. Hazards exist and will continue to exist in a world of ever-increasing technology, so risk assessment is mandatory. Professionalism requires dedication by the individual; it needs the highest competence like major basis for decision making and for avoiding errors. In work activities, authority has to derive from qualification, responsibility has to imply competence. The competence of a person rests on a double root, related to conscious-unconscious that is objective characteristics and to sensorial-subsensorial that is subjective capacities. Index Terms--Competence iceberg, competence responsibility characteristics capacities, comprehensive design and life cycle documentation, electrical safety culture, open systems globalization criteria, operation of electrical installations, risk assessment and reduction, uncertain logic and decision making.

This paper discusses the effect on humans of arcing and flashing from high-energy electrical equipment. It reviews the results of a survey of several large petrochemical facilities in the U.S. about personal protective equipment (PPE) and other equipment currently used for protection from arcing and flashing. This paper also presents the results of calculations done for typical industrial and large commercial electrical distribution systems and supports the use of personal and other protective equipment for work performed on or near high-energy electrical equipment. Index Terms - Benchmarking, curable burn distance, flash burn hazards.

Recent emphasis on safety in the workplace and reduction of damage due to fires has led to the introduction of new types of wire and cable which are insulated with materials that contain no halogens and produce less smoke and/or toxic emissions when burned. These wires and cables have been available for general building wire for several years, but not as Type SIS wire, which is required by ANSI/IEEE standards for use in switchgear equipments. Now Type SIS wire insulated with low smoke, low emission, halogen-free material is available. To investigate the performance of this wire under fire conditions, two identical equipments were built, one wired with standard SIS wire and one with low-emissions SIS wire. Wires were deliberately ignited in each cubicle and the results recorded. Measurements of the effects of emissions on the contact resistance of control devices were made, and the relative ease of cleaning was checked. A comparison of the results shows that the low-emissions wire did reduce the effects of the fire on both internal appearance of the equipment and on the contact resistance of control devices.

The recognized and generally accepted good engineering practice covering electrical safety in the workplace was adopted in the fall of 1999. The National Fire Protection Association (NFPA) accepted several significant changes to Standard 70E entitled 'Electrical Safety Requirements for Employee Workplaces.' The changes resulted from public proposals and comments based on new technology and developments, substantiated by testing. Each recommendation was reviewed, discussed and approved by the NFPA 70E Technical Committee during actions on the proposals and comments over the past two years. Text was updated to conform to the 1999 National Electrical Code. All definitions were placed in one section under Introduction. All training requirements and qualifications were placed in one chapter. Additional methods were provided for identifying the level of electrical arc flash hazard, determining safe approach distances, and selecting personal protective equipment appropriate for the degree of hazard available at the work place. Part IV was added to provide guidance for safe work practices around special electrical equipment and systems such as electrolytic cells, batteries, lasers, and power electronic equipment. Index Terms--Arc flash, electrical safety, Occupational Safety and Health Administration, shock.

The cause and prevention of electrical arcs have been explored since the early 1960's. Engineering design, construction of equipment enclosure, modifications with structural protections, and more recently, requirements for employee safe work practices have all targeted the risks of electrical arc hazards. Yet arcs accompanied by explosions continue to occur in electrical systems. Both human factors and equipment malfunctions contribute to the unexpected release of explosive electrical energy in the workplace. This paper presents experimental results of staged tests simulating the participation of workers in the test scene. Observations regarding the intensities of electrical arc flash events, variances between predicted and observed measurements, and implications for safety management are discussed. The intent is to improve understanding of how people are exposed to electrical hazards in industrial settings so that prevention strategies may be enhanced. Index Terms--Arc fault tests, arc flash, arcing, explosion.