Frank,
The 'simple' answer? Keep away from 'stuff' it may interfere with.
As for the worst case thing with high voltage? Change your antenna
arrangement.
How about hanging that ladder line from the suspended ceiling? Out of
the typical 'foot traffic zones'? Anyone asks, tell'em it's an RF
railroad line to your antenna. Sound crazy? so what, 'they' think
we're crazy anyway...
- 'Doc