Yes, you read the title correctly – Second degree burns, my wife and a chili cookoff! And it all took place at home. But, before I get into that story, let me back up a bit.
Standards such as NFPA 70E, IEEE 1584 and several others address the arc flash hazard in terms of incident energy with the severity quantified in terms of calories per square centimeter (cal/cm2). The generally accepted value for “the onset of a second degree burn” is 1.2 cal/cm2 as shown in the following examples.
The NFPA 70E definition of the Arc Flash Boundary contains an Informational Note that references the “the onset of a second degree burn on unprotected skin is likely to occur at an exposure of 1.2 cal/cm2 “
“The onset of a second-degree skin burn injury based on the Stoll curve.” is also found in Informational Note 3 of the definition of Arc Rating. Continue reading