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Good Morning Mr. Jooma I trust that your day is going well. I have a question about ground grid testing that I am hoping that you can answer. I thought I had read in the NESC at one time that there is a 5 year requirement for utilities to test their ground grids. Is this in fact true? I have been looking thru the NESC the last 2 days and can only find the testing and maint. is required but not time frame