Lightning protection and NFPA 780

Old 01-11-20, 08:35 AM
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Lightning protection and NFPA 780

I am designing a lightning protection system for my new boathouse. it sits over salt water, around 5 feet water depth. NFPA 780:2008 doesn't really cover over water structures well. Although it does consider watercraft themselves.
My structure will be alongside a seawall, with clay under turf. I'm going to suspect that I don't need to drive ground rods underwater, but that a short horiz run of grounding conductor can cross the seawall to find non-submerged dirt. Note that I already need a #6 running from a subpanel in the boathouse to one or more ground rods.
Also, any comment on the idea of submerged copper sheathing around wood piles? The structure will have a dozen 10" dia piles driven in the canal.
There is a high chance of lightning strikes in this area; my friend's sailboat was hit directly last summer, one canal over. It devastated his shore power system, aboard and ashore.
Old 01-11-20, 12:53 PM
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Is your boathouse high over current terrain ?
A boathouse is not a typical building associated with lightning strikes.
A sailboat with a tall mast would be.

Is this a saltwater area ?
The salt will kill most anything in the ground near it.

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