Why are the standards for arc flash changing?
In 2002, the National Electrical Code (NEC) expressed a need for an arc flash warning label to be attached to certain equipment. Again in 2005, the NEC was updated with even more requirements. The NFPA 70E “Electrical Safety in the Workplace ” publication made it mandatory for all non-dwelling facilities to follow these regulations. The OSHA 1910 publication further supports these regulations. What is one calorie? A calorie is the energy required to raise one gram of water one degree Celsius at one atmosphere. The onset of second-degree burns will occur at 1.2 calories per centimeter squared per second. One calorie per centimeter squared per second, can be equal to holding your finger over the tip of the hottest part of the flame of a cigarette lighter for one second. Are all arcs equal? No. You must conduct a hazardous assessment to determine the level (intensity) of energy from the arc in calories. From that you can determine the proper PPE needed. What causes an Electrical Arc? An a
