It is my opinion that 250-2(b)requires that metal manhole covers be connected to an equipment grounding conductor. Has anyone ever seen this done? As many manhole installations are outside the scope of the NEC, does the NESC have a requirement to ground conductive manhole covers? Last night a dog in Chicago was killed when it stepped on an energized manhole cover (see http://www.chicagotribune.com/news/metro/chicago/article/0,2669,SAV-0012290261,FF.html). A few years ago an 11 year old girl in an eastern city was killed in the same manner.
Don(resqcapt19)


Don(resqcapt19)