That is a rubbish system, if you use neutral as a protective earth, then as it has a resistance and carries currents, there will be a voltage drop along it. This means that if a power supply is "earthed" at one socket and an oscilloscope "earthed" at a different one, there will be a proper small (you hope) voltage between the earths and the only thing to limit the current is the mains fuse.
The best way would be to connect all your equipment earthed together and to an earth stake and to any bench metalwork, so anything that is around you is at a common potential and is connected to earth.
The next best thing is to run all your kit from one socket outlet and have your own distribution board, this will ensure that the voltage on the "earth" conductor is the same for all your kit. The problem now is that thhe buildinng metal work can be at a different potential.
Frank