Reader Feedback: Arc Flash Really So Common?

June 14, 2012
Where Did We Get Our Statistics on Electrical Accidents?

I read with interest the recent article, "Arc Flash: Not My Fault", which states: "Tens of thousands of electrical accidents still occur each year in industrial environments. According to the National Fire Protection Assn. (NFPA), hundreds of deaths and thousands of disabling injuries occur each year that are caused by shock, electrocution, arc flash and arc blast." And then you say that arc flashes are the most common electrical incidences, responsible for about 80% of the electrical-related injuries.

These statements seemed questionable to me, so I attempted to locate some substantiating statistics. First I went to the NFPA website and searched for "arc flash statistics," "electrical injury statistics," "arc flash injuries" and "electrical injuries," but all I found were reviews of the comments and reported results of the meetings in which NFPA 70 text was finalized. There are no statistics at all on that site, as far as I could tell.

I see from the first statement that electrocutions are lumped in with arc flash and arc blast. I went to the site for the National Institute for Occupational Safety and Health (NIOSH) and reviewed 17 years (1992–2008) of listed electrical fatality cases and found, as expected, that the bulk of these resulted from accidental contact with medium-voltage (MV) and high-voltage (HV) distribution lines by workers whose jobs were primarily not electrical work. The remainder, except a number of incidents you could count on the fingers of one hand, involved utility linemen working on MV and HV lines. There was not one single case of arc flash listed.

I found no statistics on the Occupational Safety & Health Administration (OSHA) site related to arc flash.

I wonder if you might be able to provide a source of the hard numbers that prompted you to make the statements quoted above. Or did you perhaps just repeat what some manufacturer of arc flash protective gear has put in its press release?

I don't want to minimize the risk of arc flash, especially for utility workers and electricians who work around MV and HV equipment. There is no amount of money that would get me to work around energized MV equipment without full protective gear to modern standards, and none that would motivate me to work HV hot under any circumstances.

In my 40 years of experience as an industrial electrician, licensed electrical contractor doing only industrial work including some MV work, and controls engineer in the industrial machinery industry, I have witnessed one arc flash incident. It was 25 years ago, where an untrained non-electrician worker used a $9 multimeter to test for blown fuses on a 480 V system. The results were spectacular and he was temporarily injured, but fortunately had no lasting injuries. His eyeglasses (non-safety) probably saved his eyesight. Compliance with OSHA regulations in place 10 years or more ago would have prevented that accident, as would common sense.