On 10/11/2020 14:49, Fredxx wrote:
Safe zones aren't applicable for the OP's networking and coaxial cables.

Good point. Too far down the thread to remember it was only a co-ax
cable but still a good idea to follow the practice. Unlike mains if you
drill through an aerial wire or network cable nothing dramatic happens
at the time. Depending how much that cable gets used it could be a few
days before you find the TV's not working or a computer has no
connectivity by which time you don't associate it with having drilled a
different bit of wall and have problems finding the cause of the trouble.

I have always assumed that a blanking plate can create a "safe zone" but
the wiki doesn't imply that and intrigued which regulation might allow
it? After all, it might not be obvious it's covering 240V cables.

It may not be officially recognised but the presence of a blanking plate
implies there was something electrical there once and there might still
be cables. I would expect anyone aware of the risks of drilling into
cables and who was aware of the concept of safe zones would regard a
blanking plate as indicating the possible presence of cables. Of course
none of this will do anything to protect the person who just blindly
drills into a wall directly above a light switch.