Q: We have gotten mixed advice from our colleagues at other utilities and can’t decide whether or not civil workers digging a foundation by hand in a hot substation should be required to wear arc protective clothing. They are inside the fence but in a new area approximately 20 feet from the nearest distribution structure. Where do we find the requirements or OSHA guidance?
A: That depends. Sometimes it depends on the criteria in the statutes, and sometimes it depends on compliance with company policy. Normally, following the guidelines of OSHA 29 CFR 1910.269(l)(8) – which establish the criteria for arc flash protection – excavation in a substation would not produce the type of work exposure you described that could create an arc flash. The location of the work and the type of work would not bring a worker within any distance of an energized bus or apparatus that would be a threat. If that’s the case, there would not be a requirement for arc-rated clothing for civil workers in a substation.
We are aware that there are utilities that require all workers, no matter what their craft or task is, to wear arc flash protective shirts while in a substation because it’s a company policy. But in regard to your question, it’s all about exposure. No exposure, no requirement for shirts. It is obvious that it’s not quite that simple for policymakers and risk analysts, who often are the people who make these decisions. Utilities must decide how to protect employees, protect the company and comply with the standards. That goal sometimes results in a blanket requirement as opposed to writing detailed criteria for when workers must suit up. The rules held by some utilities raise this question: If workers must wear arc-rated shirts, why don’t they have to wear arc-rated face protection? In fact, most of the inquiries we’ve made would seem to indicate the decision to require arc protective clothing in substations is more about gut response to the spirit of arc flash protection for contractors and employees than the result of arc flash analysis. Processes and knowledge are still expanding in the industry. As most would say, it doesn’t hurt for civil workers to wear arc protective shirts unless there is an unacceptable heat stress factor involved. In fact, there are some pretty lightweight pullover tees in Cat 2 that may help relieve both arc flash and heat stress.