Father drilled a mains cable - is this legal under current wiring regulations

My dad was drilling through a door frame (top bit) and drilled through a cable. All the electricity went off bypassing the consumer unit and blowing the electricity boards fuse that comes into the house.

I isolated the circuit and they replaced the fuse no problems but I have a couple of worries

1) The correct fuse was installed in the consumer unit - why didn't this blow?

2) Is it legal to have wires behind a door frame in the first place? The house was rewired in 1980.

3) I have also noticed a lot of back boxes (metal ones) do not have the earth fly lead attached, so when I replace sockets I always add this (using the correct insulation sleeve) and I also wondered if this was legal back in 1980.

Thaks.

 

Is your Dad ok?

 

Yep luckily he was fine, just a bit shaken up, the fuse must have blown before the drill became live.

 

check the building regs, there are specs on all this, i thought it was minimum 6 inches from any edge or corner.

 

disconection times and fault currents dear boy,each type of fuse/mcb will operate in a certain time at a certain fault current,each type of protective device has a diffrent fault/time characteristic

yep,as the wiring regs aint a statutory code,however it aint good practise

as above,but it was at one time common not to bother with the box earth, the screws holding the face plate on would do the job for you was the attitude of many sparkys,especially on lighting circuits were its not uncommon on older installations not to bother with an earth either