Cables buried in plaster, Settle arguement at work please.

[JACKC]

If 2.5 t & e is clipped to a wall and covered in plaster which is not 50mm deep, does it have to be protected by steel conduit, or am I misenterpretating the regs. If its in the 150mm safe zone, is protection reqd. Diagonals do require protection I argue, in safe zone no protection I argue and also horizontally/vertically from outlet no protection reqd as its assumed cable runs are to it. Guy at work says protect ALL if less than 50mm, I disagrea.
Clarification appreciated, lots of beer on this. I'm currently looking for me regs book, tidied up now can't find it

 

[sparkybird]

Go claim your pint! See page 53 of OSG
Have a good night!

SB

 

[Spark123]

I think you are correct, if the cable is run in a safe zone then no protection is required.
http://www.niceic.org.uk/downloads/C5-43.pdf
http://www.niceic.org.uk/downloads/concealedcables.pdf
http://www.iee.org/Publish/WireRegs...les_concealed_in_thin_walls_or_partitions.pdf

 

[RF Lighting]

Regulation 522-06-06 of BS7671 states:

"A cable concealed in a wall or partition at a depth of less than 50mm from the surfaces of the wall or partition shall:
(i) comply with Regulation 522-06-07, or
(ii) be installed within 150mm of the top of the wall or partition or within 150mm of an angle formed by two adjoining walls or partitions. Where the cable is connected to a point, accesory or switchgear on the wall or partition, the cable may be installed outside these zones only in a straight run either horizontally or vertically, to the point, accesory or switchgear."

Regulation 522-06-07 refers to covering cables with earthed metallic protection.

So in summary no protection is required in safe zones by BS7671, but it is good working practice to fit it regardless.

 

[JACKC]

Thanks for all your help, I can go to work armed with my OSG and be as smug as I want now.