Arc Flash Boundary Calculation Question
Arc Flash Boundary Calculation Question
(OP)
In the calculation of the Arc Flash Boundary, an incident energy of 1.2 Cal/cm2 in the equation as the arc flash boundary is based on the incident energy that would result to 2nd degree burn.
Now, how about if the say a client specifies that all their PPE requirement is Category 2 (8.0 Cal/cm2). Can we change the arc flash boundary based on 8.0 Cal/cm2. I know it is little bit dumb question but a clarification would help me (and others) understand the proper application of the equation.
Thanks
Now, how about if the say a client specifies that all their PPE requirement is Category 2 (8.0 Cal/cm2). Can we change the arc flash boundary based on 8.0 Cal/cm2. I know it is little bit dumb question but a clarification would help me (and others) understand the proper application of the equation.
Thanks






RE: Arc Flash Boundary Calculation Question
RE: Arc Flash Boundary Calculation Question
RE: Arc Flash Boundary Calculation Question
Indeed, incident energy does not have any risk associated with it. But incident energy coupled with time interval, within which the energy was delivered, does. For example, bare skin exposure to 1.2 cal/cm^2 incident is generally safe and oftentimes beneficial unless the energy was delivered within one (1) second time interval. In fact, only a fraction of 1.2 cal/cm^2 is required to cause the damage when delivered within shorter than 1 second time interval (see Evaluation of Onset to Second Degree Burn Energy in Arc Flash for more information). This may also explain the reason why NFPA group abandoned Category 0 and removed any references to it in new NFPA 70E year 2015 edition.