I would say no. It is down to the Designer.

For example, a low level site spark who only does what he is told, would have no input on the Design, and fits the equipment as he has been told. The Tester would also have little or no input, apart from maybe making a note that the Design may not meet the BS requirements, and to note the Design Guidelines that are provided to explain why it has been constructed the way it has, and how it does meet an equivalent safety standard.

A similar example that I am currently working on is a block of flats that has the LIfe Safety Systems secondary (back up) supply fed from the same cable as the main power incomer. It does not meet BS5839 in my view, (and an esteemed Inspector who posts here agrees), but I have no say at all in the matter, I just connect the wires. I mentioned it to the Site Manager, who knew it didnt comply, and said there was no other way of supplying the back up power. He really means that it costs more than they want to pay, and, hopefully, it wont come back to bite them on the backside if an emergency happens on the site in the future.  For this example, the Installer would have no liability, but the Designer would be liable, as his drawings clearly show both supplies from the same cable. Whether they actually try to justify it on any Certification is difficult to say. I'd hope so, but they may just forget to mention it if it is inspected.

See below Alan, but all this is because there is no effective comeback on Inspections. The Inspector needs to have serious risk of repercussions if he doesn't do the job properly. How do you "miss" inspecting and testing part of an installation?

See below Alan, but all this is because there is no effective comeback on Inspections. The Inspector needs to have serious risk of repercussions if he doesn't do the job properly. How do you "miss" inspecting and testing part of an installation?