"w_tom" writes:

Optical network interface electronics still connects to AC mains. AC
electric is equivalent to an antenna connected to optican network
electronics. That incoming wire must be earthed where it enter the
building to protect optical network electronics..

Agreed. That's why I have whole-house surge protection right at the
meter box...

FIOS installations appear to have some earthing. Cannot say why with
certainty. But an optical cable has a conductive wire within it. A
conductor so that undersground optical cable can be traced before
excavating. Have observed something from optical cable connected to
earthing. But I did not inquire as to what or why.

If that wire is connected to the chassis ground and if that in turn is
connected to the ground prong in the plug, then it should be properly
grounded (and surge protected) in the house. If that electrical signal
is just hanging there isolated from my house wiring then there is not
much I can do about it since I can't access it...

Some gas companies want interior gas lines bonded. Others do not.
You must conform to your gas company demands. However that gas pipe
gets bonded anyway when furnace or other gas appliances also use
electricity. IOW if building earthing is not provided, then (as
happened in one dwelling) building might use gas line to obtain a
return ground - may use that pipe as an alternative neutral wire.
Fortunately no one was home when a gas line gasket eventually broke
down; house exploded. Just another (and rare) reason why all
'conductive' utilities should share a common earth ground.

Agreed. I asked my utility and they said "DON'T BOND IT"...