Not usually, at least not by BS 7671. Other standards/guides/advise may differ of course (including manufacturer's instructions)
Sometimes it's a quick and dirty means of making things are bonded (e.g. using the water pipe as a bonding conductor for the gas, or for heating pipes if they're sunk into an old solid floor or some such) but it's hardly the ideal approach. Occasionally it's thought that extra bonding might help protect when things are partially dismantled (e.g. during routine boiler maintenance), especially if worried about a fault elsewhere in the installation at the same time - but the likelihood/magnitude of such things are getting to be beyond what BS 7671 considers.
Not usually, at least not by BS 7671. Other standards/guides/advise may differ of course (including manufacturer's instructions)
Sometimes it's a quick and dirty means of making things are bonded (e.g. using the water pipe as a bonding conductor for the gas, or for heating pipes if they're sunk into an old solid floor or some such) but it's hardly the ideal approach. Occasionally it's thought that extra bonding might help protect when things are partially dismantled (e.g. during routine boiler maintenance), especially if worried about a fault elsewhere in the installation at the same time - but the likelihood/magnitude of such things are getting to be beyond what BS 7671 considers.
