I recall an installation where most ground connectors in the building wer connected together, but the connection from there to ground broke.

Anything in a metal cabinet you touched gave you a severe kick.

It was found that a unit had shorted a phase to the ground and that broke a bad place in the ground circuit.

So, for safety use a GFI (ground fault interrupter) in addition to a good ground and do not use ground as a current receptor.

Erik