Are you sure about your Fault Current level and X/R Ratio?
To ensure you are using properly rated temporary grounding equipment, you must know the maximum possible fault current and the X/R value at the grounding site. Both can vary due to location and changes in your system. Once you know these variables, the appropriately tested temporary grounding (TPG) sets can be determined.
Are you sure of the Condition Your of Grounding Equipment?
Equipment used in the field can take a hard beating. It’s very important to have your TPG sets periodically tested (OSHA 1910.269 App C Section III.D.3.i; ASTM 2249) to confirm they are still in good working condition. The TPG sets need to provide a low impedance path to ground to clear a fault (OSHA 1910.269(n)(4)(i,iii)) and provide a low resistance parallel path to the lineworker that will pass virtually all of the fault current and minimize the current going through the worker to a non-hazardous level (OSHA 1910.269(n)(3)). Industry “best practice” is to test grounding equipment at least every 12 months. Check out our Ground Set Tester.
Are you sure you are creating a proper Equipotential Zone?
Required by OSHA 1910.269(n)(3), an Equipotential Zone is “a zone that minimizes differences in electric potential between conductive objects in the work area” (OSHA 1910.269 Appendix C, (III)(D)(2)(ii)). Are you making the grade? Bonding all conductive objects in the work zone minimizes the risk of a hazardous difference in potential across the worker’s body. In 2014, OSHA 1910.269 Appendix C was modified to include guidelines for how employers can comply with this Equipotential Zone requirement. Read about it here.
A comprehensive guide to grounding for de-energized construction and maintenance.