Pop` wrote:
Everything you said is correct, as best as I recall it. But what are you
citing? It sounds more like a local code than a national code.

National Electrical Code now calls for all utilities to share a
common earth ground. Water pipe as earth ground is no longer
sufficient. Water pipe is bonded to breaker box. That connection
must be within five feet of where pipe leaves earth. But that
connection is electrically better if it does not pass through a solder
joint to earth. Also meter must have a bypass ground wire. These code
requirements are for human safety have changed significantly since 1970
construction.

To make the same earthing sufficient for transistor safety means both
meeting and exceeding post 1990 National Electrical Code. Therefore an
earthing wire must be even shorter than required by code - 'less than
10 feet'. Other requirements such as not inside metallic conduit,
wires separated, no sharp bends, etc are for electric currents (ie
transients) that are beyond the scope of NEC - that will not harm
humans and that can harm transistors.

Saftety ground to a gas pipe is unique to that gas company's
requirements. NEC does not require that ground. Gas companies also
typically put an electrical insulator adjacent to the gas meter so that
their outside gas pipes are not functioning as an earth ground.
Bonding a gas pipe to breaker box would only bond gas pipes inside the
building for human safety- and again only if required by that gas
company.