It is an interesting one - ignoring for now that the omission of an RCD to the bathroom lights may be more serious if there is inadequate bonding as well, there is a more general question.

The thinking is that the problem with private accommodation is that the folk that live in it are likely to fiddle with it, and drill holes to hang pictures, take light fittings down and replace them, perhaps incorrectly, when painting the ceiling etc.This is less likely if the person living there does not feel it is their own home - so long term tenants may do things that folk in a holiday let may not, and a paid up home owner may do more major works. It is not clear if this view is correct - student rental may be short term, but some odd things happen to it sometimes. So the RCD protects a bit against those picture hook and disconnected CPC incidents.

Where the supply comes from and if it shares a main fuse with another flat, a dairy farm or a pub car park is not that relevant,  is not really so important as to who is using the supply and for what, at least unless that imposes other conditions, such as a TT supply (the dairy farm perhaps).

Personally, I'd consider overnight accommodation anywhere to require the same standard of safety as domestic, even if in law that is not always true. (tents caravans boats.. ) I suspect others will disagree a bit. I'm not surprised that you see conflicting inspection reports - not only is it a bit subjective, even if it was not, each case is different, and may hinge on other factors as well  - bathroom fan on the lights needs an RCD perhaps if in zones. Attempts to produce a 'see this. tick that' simple set of rules are likely to throw up quite a few exceptions, despite the fact that various organisations have had a go at this over the years.
Good really, as it would make inspecting a very easy job requiring no technical knowledge. If anything the reverse is true - the inspector has to know enough about all possible situations and installation methods to make an informed decision. The installer just has to have his/her favourite recipes for specific situations.

Mike.

Yes I would agree with what your saying, particularly with bathroom lighting, i would expect a separate observation for any circuits feeding or passing through a bathroom to be listed with a C3, potentially with an observation for lack of supplementary bonding to follow which would likely require a C2 as Reg 701.415.2 has then not been met. This would be expected on any install of course. 

I would agree with the premise of what your saying about overnight accommodation particularly semi permanent, but as there are difference's for some installations (care homes etc) I was just interested in other peoples thoughts.

I definitely agree with your last statement, even if in my experience this is not the case, and that the industry and wider construction industry has a real lack of competency starting to grow. To many quick routes to becoming an electrician and not enough accountability. Lots of reports out there I have seen aren't worth the paper they are printed on, but I'm sure that is a separate discussion that would prompt lots of heated arguments. 

Domestic lighting circuits need 30mA RCD protection these days even if there aren't any concealed cables - I suspect the reasoning has something to do with the continued existence of BC and ES lampholders where it's far from impossible to put fingers on live parts - especially if fumbling to replace a blown lamp in the dark.

Usually C2 for sockets expected to feed equipment outdoors.

   - Andy.

Accommodation at work is not domestic.

There is a definition in S. 53 of the Health and Safety at Work Etc. Act 1974:

"domestic premises” means premises occupied as a private dwelling (including any garden, yard, garage, outhouse or other appurtenance of such premises which is not used in common by the occupants of more than one such dwelling), and “non-domestic premises” shall be construed accordingly;

Interested in what you guys would code an LED lighting circuit with type AC RCD

What action if any would you take if asked to change GU10 down lights for LED on a type AC RCD or no RCD circuit. I think the right action would be to fit a type A RCD but would be interest in what others think. but on the other hand its a minor works certificate no additions to the circuit just changing the fitting.

What does the manufacturer specify?

No more than C3. I say that not least because when I installed my installation (what else can you install? :-) ) to BS 7671: 2018 a bit before the drawbridge came down, I deliberately omitted RCD protection because I could. They are well beyond reach and it is difficult to see how they could ever present a shock risk.

Concerning type A vs type AC: my RCBOs at home are all type A because that is what the manufacturer (Eaton) supplies. A couple of years ago I had a problem inasmuch as a boiler specified type A, but Schneider only supplied type AC. Type A was in the Irish catalogue, but I could not get them.

Sometimes you cannot win.