John H>> The NEC does get revised periodically, 2002 the most recent.
> The 2005 version has been out for several months.
They must review it more often than I (and others) are expecting. The electrician I hired over the winter was interested in the 2002 code book I had.
The biggest effect on building grounding systems has been the decrease in reliance on metal plumbing, due to the usage of plastic piping.
I got my books from
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which are more user friendly than the actual code books, which are more like legalese.