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Garments respond differently to four types of arc exposures. Moisture in arc exposed garments can alter their appearance in ways not typically observed in standardized arc flash testing such as ASTM F1959, IEC 61482-1-1, IEC 61482-1-2 or ASTM F2621. Color change commonly seen in garments exposed to standard tests do not occur as expected when garments are moist. This information may be useful in accident investigation and hazard assessment. The four types of arc exposures described herein are: Radiated Arc, Ejected Arc, Arc-in-a-box, and a “Tracking” Arc. Two of these arc exposures can be described as plasma-rich and the other two are only circumstantially plasma-rich depending on equipment configuration, duration, voltage, and fault current level. New methods to reduce arc hazards, such as blankets meeting ASTM F2676 and shields meeting ASTM F2522 and how they relate to potential arc exposures will also be discussed. [ABSTRACT FROM PUBLISHER]

Power transformer is one of the most important components in a power system. It experiences thermal and electrical stresses during its operation. The insulation system consisting of mineral oil and the insulation paper used in transformer undergoes chemical changes under these stresses and gases are generated. These gases dissolve in oil. The extracted dissolved gases are analysed in the laboratory using gas chromatograph. The fault identifications in a transformer are based on certain key- gas ratios. International standards such as IEEE and ASTM are in use for fault identification. However, these standards are not able to diagnose the fault under certain conditions. Hence, there is a need to improve the diagnostic accuracy. In this paper an attempt has been made to diagnose the faults in a power transformer using a three level perceptron network. Three types of neural network simulation models are developed using MATLAB™ Software and trained using the IEC TC 10 databases of faulty equipments inspected in service. The outputs of the Neural Network models are compared with the IEEE and ASTM methods. The comparison of the results indicates that the condition assessments offered by the models are capable of predicting the fault with higher success rate than the conventional diagnostic methods. [ABSTRACT FROM PUBLISHER]

PPE exposed to arc flash is not always designed for arc flash exposures. This paper discusses the critical PPE rated for arc flash exposures for electrical workers and the test methods employed for those ratings. It also further explores other PPE which is frequently exposed to arc flash but which is not arc-rated. The purpose of the paper is to provide some guidelines on proper use and dangers posed by using the improper materials in arc flash exposures until standards have caught up with the state of the art research. [ABSTRACT FROM PUBLISHER]

Common mistakes made in Personal Protective Equipment (PPE) selection by a cross section of industry, specifically industrial controls workers, can make the job less safe and more difficult to perform. The NFPA 70E standard has made the workplace safer for the average electrical worker but some employers, and even some employees, make life much more difficult by improper PPE choices or PPE overkill. The paper will explore mistakes commonly made in the selection of arc flash suits, daily work wear, faceshields, and issues with gloves and arc flash protection. [ABSTRACT FROM PUBLISHER]

PPE exposed to arc flash is not always designed for arc flash exposures. This paper discusses the critical PPE rated for arc flash exposures for electrical workers and the test methods employed for those ratings. It also further explores other PPE which is frequently exposed to arc flash but which is not arc-rated. The purpose of the paper is to provide some guidelines on proper use and dangers posed by using the improper materials in arc flash exposures until standards have caught up with the state of the art research. [ABSTRACT FROM PUBLISHER]

PPE in the electric arc has been evolving since the early 1990's. With the introduction of OSHA Safety and Health Standards in the US and arc test methods in ASTM International, the growth of knowledge in PPE and proliferation of PPE for electric arc has grown throughout the world. In 1995, NFPA 70E began addressing arc flash boundaries and NESC added safety requirements for electrical safety. Misunderstandings and errors in marketing still abound but knowledgeable users, manufacturers and researchers have helped 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 CSA Z462 have codified clothing for electric arc. Brazil, Peru, Russia, recently South Africa, New Zealand, and Australia are codifying laws related to arc flash PPE so the international focus is critical. [ABSTRACT FROM PUBLISHER]