The million dollar question…
Can you just use the PPE Charts in the NFPA?
If I had a dollar for every time I’ve been asked that question… it seems like a fair question while discussing the need to conduct an Arc Flash Analysis. After all, the NFPA 70E states that a person “Can” use those charts to simply choose what PPE to wear while working in an electrical enclosure. OSHA makes it very clear that a worker must have and use the correct PPE. In fact, as we have seen so many in recent years they will fine employers up to a half million dollars should the employee be caught without the correct PPE.
Having been faced with the opportunity to discuss this issue with several facility Safety Directors who, for some strange reason want to argue about keeping their workers safe, I thought I would shed some very important light on this subject.
Let’s take a close look at the regulation…
NFPA 70E Section 130.7(9) says you are allowed to use the PPE chart in lieu of an Arc Flash Hazard Analysis if… and here is the big “IF”… The electrical supply circuit upstream has a minimum requirement of “a maximum of 25,000 short circuit amps, AND the clearing time of the protection device is less than 2 cycles”.
First off, without a short circuit study, there is no way to know the short circuit current upstream to every point that your workers may be exposed, and without a protective device study there is very little way to know the clearing time of the protective devices in the circuit. This information is what is calculated and studied in an “Arc Flash Analysis”.
So, in short, while the NFPA does give you another method to determine the level of PPE needed at every panel, you still need the information gathered by a typical Arc Flash Analysis to determine if you can in fact use the PPE Chart!
Dave Carpenter, Electrical Engineer
ITU President
