Safe zones still apply under the 17th edition.
The reason capping is used it protection until the wall is covered, in other words from the plasterers trowel. No other reason. If protection against impact is specified then you need to look elsewhere.
It's not required for a 'proper job' if it's only a chase you're filling. I do however always use it but not metal, pvc which is the more popular choice.
Thanks for confirming the requirements of 17th edition regarding safe zones. I always like to keep up & you saved me the trouble of checking at some point; I thought the new requirements would have made them irrelevant, at least from a “safety” viewpoint but obviously not.
I do understand & appreciate all of what your saying; I also know PVC is more commonly used for obvious reasons but just think for a minute about what I’m saying; steel capping has the additional benefit over plastic regarding a significant, initial resistance to penetration from an ignorant DIYers masonry drill bit. For the few extra pence it costs, do you not think a steel cap is a better bet than plastic which even a masonry drill will just sail through & then the lights go out? I can honestly tell you, I’ve had quite a few converts!
My original post about a “proper job” was directed at plastering over paper & wood as a filler; it is, after all, the plastering forum! The “steel capping” comment was thrown in because I genuinely believe it gives additional benefits over plastic & that’s what I always do cos it don’t really cost much extra. It had nothing to do with electrical regs. requirements which, for some reason, you seem to have specifically picked up on!
Because of my long & varied background, I do have electrical qualifications (among others) & historically, a strong background in electrickery including hardwired control & signalling systems, albeit in a commercial environment. It’s not what’s currently floating my boat but that’s due to both personal circumstances & advancing technology; but I do like to keep up!