I have a safety issue that maybe someone can provide me a better explanation and/or point me in the direction to where I can find the correct information.
We are to begin working next to a fence line around a 500kv distribution line. The distance to the switches is well above the minimum clearance established by OSHA and we are grounding all equipment/material to the grounding cable (located on the fence that goes to the underground grid) for an added safety measure. We are told to keep a minimum distance of 10' away from the fence in case there is failure in the distribution system (lightning strike, switch failure, etc.) and the potential of the underground grounding grid to be energized and prevent any pipe within 5-10 feet of the fence to act as a conductor.
My questions:
1. If we are grounding to the fence cable and there is a failure to the system, can the electric current go up our grounding cable and cause a shock potential to the equipment / material it is in contact?
2. To dissipate any static potential we are grounding all material before being touched. Should a separate grounding source be used or is it best to attach to the ground on the fence. And, if we do, will the potential in Question #1 come into effect.
3. The grounding grid extends 5' outside the fence, as indicated by the colored stone. Is a 10' clearance from the fence an adequate distance to prevent the pipe from acting as a conductor in case of a failure, as well as, minimize any static charge?
I would appreciate any assistance (answers, information, resource direction) in this matter. Thank you for your assistance. I can be reached at my email address below.
Rillor
Safety Coordinator
sparker@fast.net
