250.64(b)

[anbm]

250.64(B) ...a #4 awg or larger copper or aluminum grounding electrode conductor shall be protected where exposed to physical damage.


If we run #250kCM ground riser inside the building connect all electrical rooms' ground bars and bond to building steel, water metal pipe, etc. I assume we can run this wire without conduit as long as we secure it?

How do you guys understand the term "exposed to physical damage" above? Does this mean the conductor exposed to conditions of bad weather? rain, snow, etc? Thanks!

 

[Buck Parrish]

"Physical Damage" is physical such as a hallway with carts. They could bump it. Any thing that could damage it.
The weather IMO does not count. Although all connections and connector devices must be rated for the purpose they serve.

 

[anbm]

couldn't think anything can damage this large wire if we secure it to the bldg structure...