Why "No RCD protection on lighting circuit"?

[ericmark]

I do like PBC_1966 comments they are very valid. The problem is we want to shift blame. Once reported does not matter what code then we have transferred the onus to some one else. It was said the 4 code system failed because owners could not work out what was informative and what needed action, but the 3 code system is the same. We can however put items in notes so we can still report items which don't attract a code.

The Electrical Safety Council seem to have taken in on themselves to list what should and what should not be reported. And what code should be given. To my mind it is all wrong. If I am testing an installation I feel any portable appliance plugged in at the time is beyond my remit. Neither is it up to me to comment that there are not enough outlets.

To test a house just completed and fail it because there are driers plugged in with leads going through door ways is silly, as we know once the house is in use that would never happen. It seems common sense is not very common, we just follow the rules laid out by some one who thinks he knows it all, and these people who think they know it all are especial annoying to those of us that do.

To my mind we are tradesmen and should act as such. We should be allowed to use our knowledge and experience rather than following some book. I think the BS7671:2008 is a good guide. It's not law it's just a guide to what is good practice. But to then publish guides to the guide seems to be going OTT.

I still don't understand why when taking the C&G2382 we should be asked questions about the appendix? It is an appendix not the regulation so why ask questions on it?

To my mind questions should test understanding. I know now changed but the question asking if a competent person can look after the safety of others or just himself was silly. What is needed is not to test ability to read but ability to interpret the regulations.

So the question "What is the maximum length of an unfused spur off a 32A ring final circuit"
A) 3 meters.
B) No limit as long as line - neutral impedance is better than 1.54 and line - earth better than 300Ω when RCD protected.
C) 50 meters.
D) As defined by 434.2.1.

I am not giving an answer as to be frank I am not sure what it is. But a question like this tests the ability to interpret rather than simple reading parrot fashion. We get all our bits of paper but we are not really qualified until we have completed or journeyman. My dad after doing a 5 year apprenticeship had to serve 6 months with four other firms before he was considered as a tradesmen. In other words 7 years to qualify. To my mind having to work 7 years in the trade before being allowed to work solo was good. Even the poor apprentice in 7 years will pick up enough to ensure he knows his trade.

As to allied trades that's a harder question. I admit I trained as an Auto Electrician not a simple electrician. When I made the sidewards move I will also admit I made mistakes. This was in 1977 I knew electrics what I didn't know was the regulations. I worked for a large firm SLD pumps. As a result I had some back-up to help me move. When employed the comment was they needed some one who could repair traffic lights and pumps. I knew the traffic lights like the back of my hand, and they thought easier to teach me pumps than teach a pump man traffic lights.

In 1980 I went to work in Algeria and that was a steep learning curve. Dutch system with Siemens bottle fuses and German sockets. After that it was the Falklands forget the rule book it was keep it going if possible in a safe way. Did not do bad 20 coffins sent out start of job and 4 returned at end unused. That includes heart attacks as well as accidents.

On returning to UK the BSi had combined with IEE as it was then to issue the 16th Edition. For the first time people were quoting rules. Before that the wiring regulations never left the managers office. Since then I have taken my exams and now have level 5 qualifications, but to be frank having a degree does not help in every day electrics. I still make errors like everyone else. OK as a member of the IET and attending meetings I may gain some facts which the simple electrician is not given.

But to be told what I should pass or fail seems to me to be missing the whole point of education. I consider myself as a tradesman and I feel I should be able to judge what is safe without having to read books, I know circuits with an RCD are safer than those without but I also realise we need to see where we are going. Where we have battery back-up then the RCD is not a problem, but without that the idea of being plunged into darkness being safe does not seem to follow my line of thinking.

We live in a world of method statements and risk assessments and to ignore them and hide behind the wiring regulations seems to me flawed.

To me we should be asking which exposes occupants to the least danger. So a house with a central stair case will likely be better with no RCD to stair case lights and one with windows lighting the stair case will be likely better with RCD protection. We have to ballance chance of electric shock to falling down the stairs.

Problem is obtaining data. Injurys due to falling down stairs due to failed lighting due to RCD tripping v injurys due to electric shock which a RCD would have stopped. A RCD does not stop us getting an electric shock. It only protects when the fault will cause the RCD to trip before we make contact with the power. So drilling through cable it offers no protection best it can offer is reduced contact time so in real terms it only protects where the fault is not due to direct human action but indirect like a water leak.

If we are looking at a water leak then a 100 mA RCD would protect just as well as a 30 mA RCD they will both trip before a human can contact the power. The quoted fact that 30 mA is the limit a human can take has really nothing to do with selecting the RCD size. A 30 mA RCD can still take 40 ms to trip which is enough to kill some one. But with a 100 mA RCD loss of lighting is less likely to happen. I would personaly access that there is less risk using a 100 mA RCD than a 30 mA RCD when falls due to lighting failure are taken into account.

But it's not up to me, it's up to those people who think they know it all?
C)

 

[ban-all-sheds]

You are being really tedious, presumably in an attempt to 'win' (in your eyes)!

You know jolly well what I'm saying - that I personally find it laughable (and doubt that I am alone) that the regulations are such that the situations we were talking about have to be regarded as non-compliant.

I really am struggling to know what you are saying. I read your words, but they make no sense.

Do you find the whole concept of regulations changing to be laughable?

If people don't comply with the regulations then what they have done is non-compliant - that's the way it works. And it doesn't matter whether the regulations they contravened had been in force for a year, or a day, or an hour, or a minute - non-compliance is non-compliance, and to find the idea that non-compliance should be regarded as non compliance to be laughable is so utterly bizarre that I really cannot make any sense of it at all. It genuinely makes no sense.

So I'm sorry you are finding it tedious, but the reason that this has dragged on so long is your refusal/inability to put forward a set of rules which you think should be in place to allow for a "little bit" of non-compliance if there is already a "fair amount" of old stuff in place and it hasn't been "that long" since the regulations changed, and which make sense.

Am I safe in assuming that you would prefer it if the regulations were not laughable? If so, you must surely know how you would like to see them worded so as not to be laughable?

I'll ask you again - how would you word the final sentence of 522.6.202, to provide a codified method, which could be consistently applied by everybody, to incorporate your concepts of what needs to be allowed for it to no longer be laughable?

 

[Risteard]

the thing I find laughable is to 'make a fuss' about (let alone 'code' as 'potentially dangerous and needing urgent attention') a few feet of non-RCD-protected new buried cable in an installation in which 95% of the buried cables are (without 'fuss') not RCD protected.

A periodic inspection should have recommendations attached to any lack of RCD protection where this is now required by the Regulations. It is completely irrelevant whether it is new or old wiring. Indeed the notes appended to the model forms explicitly state that any ommission of required RCD protection must be coded.

 

[PBC_1966]

To my mind we are tradesmen and should act as such. We should be allowed to use our knowledge and experience rather than following some book.

{.....}

But to be told what I should pass or fail seems to me to be missing the whole point of education.

Indeed. Surely as somebody with the requisite knowledge and experience it is up to you to apply that knowledge and experience to the particular situation at hand to assess whether some small non-compliance with the current guidelines is acceptable, or even desirable? Or to be able to assess whether it might not be ideal in a perfect world, but it's not an unreasonable deviation given how much work would be involved to achieve full compliance and to use your own judgment to deem it a reasonable compromise? There are so many variations in what one might encounter, that surely that's the whole point of having that education, otherwise "electricians" might just as well be given a flowchart to follow with simple yes/no answers at each branch so they don't really have to know or understand anything.

 

[Risteard]

red/black cable is going to be around in British homes for decades to come, so they'll need to know it anyway.

Foreign labour is unlikely to be flown in to extend a circuit in a house. It is much more likely that they would be involved with major construction projects where they are liable to be supervised and directed by chargehands; foremen, etc.

So knowing harmonised colours ought to be sufficient.

It is a nonsense to suggest that courts will endorse the use of pre-harmonised colours in contravention of Standards and the norm, however, and it would also certainly be a breach of the terms of the contract.

 

[EFLImpudence]

So the question "What is the maximum length of an unfused spur off a 32A ring final circuit"

I presume you mean with 2.5mm²

A) 3 meters.

No, you are not having to comply with 434.2.1

B) No limit

Yes, no specified length limit.

as long as line - neutral impedance is better than 1.54 and line - earth better than 300Ω when RCD protected.

Surely you mean line - earth (Zs - 1.37Ω now).
If you are relying on an RCD, surely <7666Ω (30mA)

C) 50 meters.

Not as a blanket figure.

D) As defined by 434.2.1.

No, it comes under 434.2.2 and the relevant device is the B32 MCB.

 

[ericmark]

1.54Ω line - neutral with a 13A protective device would give just under the volt drop permitted. I was not really trying to say that should be the question, however questions of that type would require the student to understand rather than simply read the regulations. I realise the 3 meter limit for unprotected cable is a controversial one. However really it should be simple to read the regulations and know the answer. The fact that electricians argue over the answer really points out the problem with BS7671:2008. It does not matter what the answer is, the point is we should be able the read the regulations and know the correct answer.

I read the regulation on RCD protection and although it would be crazy to require RCD protection for a SELV cable buried in the wall with the original BS7671:2008 it seemed to require it even though I can't find a single 12 volt RCD for sale. Maybe the regulation now states low voltage.

As to reduced low voltage again trying to work out what is required is hard. Do we still need RCD protection and more to the point would it work at only 55 volt to earth? I have found some in-line units but no panel mounted 55 volt RCD's.

 

[JohnW2]

... the reason that this has dragged on so long is your refusal/inability to put forward a set of rules which you think should be in place to allow for a "little bit" of non-compliance if there is already a "fair amount" of old stuff in place and it hasn't been "that long" since the regulations changed, and which make sense.

It would undoubtedly take years, of discussion and debate within learned committees, followed by public consultation (undoubtedly with a lot of disagreement between the parties involved) to come up with an agreed "set of rules" which were both reasonable and "made sense", so it's a bit ridiculous to criticise my "refusal/inability" to come up with 'an answer' on the spur of the moment.

One of the greatest problems any such discussions would have to attempt to address would be that of multiple/progressive new works over a period of time. If it were not for that complication, the regulations could simply require that, to be compliant, any new works must not increase the amount of buried non-RCD-protected cable, or the number of non-RCD-protected sockets, by more than X% (that being 5%, 10% or whatever).

... but it's not going to happen, so we are stuck with a situation which "makes little (common) sense".

Kind Regards, John

 

[ban-all-sheds]

Indeed, I certainly could not look at most of these examples and say that I would consider something to cease to be reasonably safe after X years, simply because X years have passed since some regulation changed. I'm looking at it on the basis of my knowledge and experience of whether I consider something to be reasonably safe, regardless of whether whatever it is ceased to comply with the IEE Wiring Regulations/BS7671 last year or 40 years ago. If it was reasonably safe in 1980, it will still be just as safe in 1990, and just as safe in 2000, and just as safe today, short of something else changing to affect the situation (as with water-pipe earthing).

It may surprise you to learn that I have a great deal of sympathy with that view. I have always said (and in fact have been thrown off websites for saying, when their policy was to lie and deny), that there is no requirement to comply with BS 7671. In terms of what the law requires, you could indeed make a case to say that complying with an earlier version of the regulations, or that complying with regulations A, B & C but not X, Y & Z was reasonably safe. And if you were right, and confident, and articulate, and had independently verifiable competence, and properly presented your case, your position would be unassailable. But you would face an uphill struggle in getting the authorities to agree with you. Were you to be prepared to push it all the way to a court case, the fielding of expert witnesses etc, you might well prevail, but would you want to go that far? Would anybody?

The flip side of the "freedom" to choose how to "make reasonable provision for safety" is that there is no codified way of doing so which you can say will be your method and which those charged with ensuring that you do comply can easily verify except compliance with BS 7671. So that is by such an enormous margin the easiest, cheapest and most efficient way to comply with Part P that it's what people do. And you cannot criticise them for doing that. You would too, if it was your financial well-being at stake, without a moment's hesitation.

What you and John seem to be failing to grasp is that once you have elected to comply with BS 7671 you have to comply with it. You have surrendered your right to use it as a "guide", and to cherry pick from different provisions from different dates, and to say "well it doesn't really matter if I don't comply with this reg because it's only a little bit of cable and there's so much like it already there". The regulations do not allow that. The Building Regulations probably do, but the Wiring Regulations definitely do not.

British electricians working to BS7671 and in the various schemes are pretty much already insisting that anything installed new has to comply with the current rules, as in providing RCD protection for that new 4 ft. length of cable to a switch even though there are dozens of similar switch drops not so protected.

Well of course they do - that's how regulations work. They are not "insisting that anything installed new has to comply with the current rules" because they are jobsworths, or because they can't think, or because they belong to a scheme, they are insisting on it because it is what the regulations insist on. They have no choice, and frankly it is invidious for someone to say that their position is laughable, or if there are non-compliances that it is laughable for someone inspecting the work to note them.

Consider the analogy of a road where the speed limit has changed. Yesterday it was 60mph, today it is 50. Would you carry on doing 60mph, on the grounds that it's only 10% over the new limit, that if 60 was OK yesterday why is it not OK today, and anyway there are still loads of roads just like it where the limit is still 60? Would you laugh at other drivers who did stick to the new limit? Would you tell plod that it was laughable for him to be enforcing it?

Would it be a case of refusing to do any job, however small, unless everything within the installation were brought up to current regulations? Imagine, for example, somebody asking an electrician to add a light somewhere and being told that the whole house needs to be rewired to put all the cables into safe zones! If the electrical trade went down that route, I fear it would actually have an adverse effect on safety, as more people who really shouldn't be tackling electrical work would "have a go" instead.

I think the idea of requiring improvements to older installations has merit. Whether in practice there is much that could practically be required is, of course, another matter. We already have at least one example where it is done - earthing and bonding. Clearly enforced rewires could not be done.

Or perhaps it would be done through Building Regulations any time somebody applied for something. There are actually a few instances of a situation like that here in California, e.g. if you apply for a building permit for certain things now, you're required to change all your plumbung fixtures to the newer water-saving types, even if your work has absolutely nothing to do with them.

Re my earlier question about replacing the previous ones - that's not unheard of here with doors, when people have altered a property in a way which introduces a requirement for fire-doors, they quite often store their lovely period doors and put them back once the work has been signed off.

Or how about when a property changes hands? The trouble there is that we could, once again, be talking about a complete rewire in many cases to bring everything up to the current regulations,

I don't think that any sane person would ever suggest that sort of thing. And it's hard to see how any changes/updates/renewals/etc could be mandated without changing the status of BS 7671, which for some reason they don't want to do.

 

[ban-all-sheds]

Foreign labour is unlikely to be flown in to extend a circuit in a house. It is much more likely that they would be involved with major construction projects where they are liable to be supervised and directed by chargehands; foremen, etc.

And that is outwith the scope of Part P, at least in the context of changes to an existing installation, and therefore irrelevant.

It is a nonsense to suggest that courts will endorse the use of pre-harmonised colours in contravention of Standards

Were it ever to be in court then there would be two problems to overcome regarding that.

1) The law does not require any particular colours to be used, and therefore the court has no jurisdiction there.

2) You'd need to find an expert witness prepared to testify on oath that continuing the use of the existing colours was not reasonably safe.

it would also certainly be a breach of the terms of the contract.

Contractual issues are easily avoided. Particularly as 120.3 would allow an EIC to be issued with the continued use of the existing colours documented as a departure.

 

[ban-all-sheds]

It would undoubtedly take years, of discussion and debate within learned committees, followed by public consultation (undoubtedly with a lot of disagreement between the parties involved) to come up with an agreed "set of rules" which were both reasonable and "made sense", so it's a bit ridiculous to criticise my "refusal/inability" to come up with 'an answer' on the spur of the moment.

That's a cop-out.

Of course the process would be as you describe, but does that mean that you would be incapable of responding to any consultation? That you would not have an opinion until after the great and the good had given theirs?

You think that this is a laughable requirement:

Where indent (i) but not indent (ii) applies, the cable shall be provided with additional protection by means of an RCD having the characteristics specified in Regulation 415.1.1.

You really have no right to voice that opinion if you cannot propose an alternative way to word it, or propose that it simply be done away with. At which point I start to wonder if what you find laughable is any change to the regulations at all.

One of the greatest problems any such discussions would have to attempt to address would be that of multiple/progressive new works over a period of time. If it were not for that complication, the regulations could simply require that, to be compliant, any new works must not increase the amount of buried non-RCD-protected cable, or the number of non-RCD-protected sockets, by more than X% (that being 5%, 10% or whatever).

You think that's a common sense approach? Sockets are easy enough to count, but how would someone determine how much unprotected buried cable there already was? There would have to be a way. And with the number-of-sockets, how long do you think it would be before people started dividing up the adding of new ones into multiple separate jobs to keep under the threshold? Particularly as each unprotected one they add raises the threshold for the next one. How long do you think it would be before someone claims that it's OK to continually re-evaluate the numbers during the process of adding more, e.g. (assuming a 10% figure) "I had 28 sockets and I wanted 5 more, which is >10%, but once I'd added the first two I was able to add another 3"?

You know that people will always look for ways to wriggle out of having to comply with things, and to "interpret" regulations in a way which justifies their wriggling. Do you think it is common sense to create new ways in which they could get out of complying with a changed regulation? If you did I would again have to wonder if what you would really be opposed to was the new requirement itself.

but it's not going to happen, so we are stuck with a situation which "makes little (common) sense".

Well - so you believe. I believe that it makes perfect sense, once a regulation has changed or a new one has been introduced and the date of it coming into force has passed, that people should be expected to comply with it if it applies to what they are doing.

 

[ban-all-sheds]

The Electrical Safety Council seem to have taken in on themselves to list what should and what should not be reported. And what code should be given. To my mind it is all wrong.

You need to remember who the ESC really are, and what their typical member is capable of.

 

[JohnW2]

You really have no right to voice that opinion if you cannot propose an alternative way to word it, or propose that it simply be done away with.

As I said, it's a very complex issue, primarily due to problems of implementation, but I did go on to mention one possible approach. However, as you rightly observed ...

You think that's a common sense approach? Sockets are easy enough to count, but how would someone determine how much unprotected buried cable there already was? There would have to be a way. ...

As I said, there would be serious problems of implementation, which would require endless discussion and debate, not the least about practicalities.

You know that people will always look for ways to wriggle out of having to comply with things, and to "interpret" regulations in a way which justifies their wriggling.

Exactly, hence the serious difficulties.

Well - so you believe. I believe that it makes perfect sense, once a regulation has changed or a new one has been introduced and the date of it coming into force has passed, that people should be expected to comply with it if it applies to what they are doing.

Of course - we agree about that. However, IF a way could be found to word and implement an alternative, that does not mean that a regulation necessarily has to require that a tiny proportion of an installation has to be to the 'new standard' whilst the great majority of the installation is not (and does not have to be) to that 'new standard'. It depends entirely on how the regulation is worded.

One approach (albeit still with plenty of 'wriggle room', particularly if the reg were not worded optimally) would be for some of these new regulations to apply only to 'new installations' (as is the case with many of the Building Regs) - but I imagine that much of the problem/wriggling would then be in relation to the definition of a 'new installation'.

As I intimated before, I would have a lot of sympathy with the concept of requiring all installations to be fully compliant with a regulation "X years" after that regulation came into force - but attempting to implement, let alone 'police', that would probably present almost insuperable problems.

Kind Regards, John

 

[ban-all-sheds]

As I said, it's a very complex issue, primarily due to problems of implementation, but I did go on to mention one possible approach.

No - you suggested something totally unworkable. It was not a possible approach.

As I said, there would be serious problems of implementation, which would require endless discussion and debate, not the least about practicalities.

And despite those serious problems, and the amount of discussion needed about the practicalities, you think the regulations are laughable because they haven't had those discussions, and haven't overcome the problems, and haven't put something in place which would allow some people to avoid complying with the regulations in force.

I see.

Of course - we agree about that.

But you don't agree with it. You think that some people should not have to comply with the regulations in force, and that they should be changed so that they no longer apply to them. You think that for two identical jobs, let's say adding a light switch, someone in a 1-bed flat should have to have RCD protection added to the circuit, but someone in a 20-bed mansion should not, and you believe that that would not be laughable.

However, IF a way could be found to word and implement an alternative, that does not mean that a regulation necessarily has to require that a tiny proportion of an installation has to be to the 'new standard' whilst the great majority of the installation is not (and does not have to be) to that 'new standard'. It depends entirely on how the regulation is worded.

But why?

Just what is the root of your objection to the principle that when the regulations change everybody has to comply with them?

One approach (albeit still with plenty of 'wriggle room', particularly if the reg were not worded optimally) would be for some of these new regulations to apply only to 'new installations' (as is the case with many of the Building Regs) - but I imagine that much of the problem/wriggling would then be in relation to the definition of a 'new installation'.

That is such a fundamental change to the basis of how the regulations work that I am now convinced, beyond reasonable doubt, that what you really don't like is the whole idea of regulations changing.

 

[PBC_1966]

Foreign labour is unlikely to be flown in to extend a circuit in a house. It is much more likely that they would be involved with major construction projects where they are liable to be supervised and directed by chargehands; foremen, etc.

So knowing harmonised colours ought to be sufficient.

Fair point, but on the general principle that was hardly a good reason for the change in cable colors in itself. I've always thought the change in colors, just to "be in line" with Europe was ridiculous. In making it the same system for that foreign labor it's introduced completely unnecessary complications and confusion for the much larger British labor force, and general population. Besides, foreign workers still have to deal with BS1363 sockets and all the other things peculiar to the U.K., so surely they should be able to deal with red/yellow/blue/black wiring?

It may surprise you to learn that I have a great deal of sympathy with that view. I have always said (and in fact have been thrown off websites for saying, when their policy was to lie and deny), that there is no requirement to comply with BS 7671. In terms of what the law requires, you could indeed make a case to say that complying with an earlier version of the regulations, or that complying with regulations A, B & C but not X, Y & Z was reasonably safe. And if you were right, and confident, and articulate, and had independently verifiable competence, and properly presented your case, your position would be unassailable. But you would face an uphill struggle in getting the authorities to agree with you.

And therein lies the problem, which I've commented on elsewhere, that the electrical trade is so aligned with BS7671 that it's often difficult to get anyone from that trade to think outside of it, even though it has never been a legal requirement.

Here in the U.S. the National Electrical Code is published by the National Fire Protection Association and is not law in itself, but is adopted by every state into its building code and thus becomes the legally required standard, rightly or wrongly. States can also make their own amendments if they wish (most often to impose stricter requirements than the NEC), and sometimes even counties and cities make local amendments (as in the example I've quoted before of the City of Chicago requiring everything to be in conduit). Whatever we might think of some new NEC rule (and some are just as controversial as changes to BS7671), once that new edition of the NEC is adopted by a state, it becomes the legal requirement for new work. If a building inspector wants to fail an installation, he has to be able to cite the specific rule it violates. Of course, I've heard of cases in which an inspector is clearly wrong but it's a relatively small matter to do what he insists upon anyway and people don't bother to argue, but if it's something important it's much easier to challenge when the rules are clear and are the legal standard.

As you say, in the U.K. it would be much harder to argue because of the much more vague requirement of just "reasonable provision for safety."

What you and John seem to be failing to grasp is that once you have elected to comply with BS 7671 you have to comply with it. You have surrendered your right to use it as a "guide", and to cherry pick from different provisions from different dates, and to say "well it doesn't really matter if I don't comply with this reg because it's only a little bit of cable and there's so much like it already there". The regulations do not allow that. The Building Regulations probably do, but the Wiring Regulations definitely do not.

Yes, but if you were doing work on your own home and did not want to follow every last detail of the current edition of BS7671, surely you would not elect to do so on the plans?

And what if you were just submitting a building notice to add a new circuit in your house, without submitting full plans setting out how you intended to comply? You've not elected any particular method of compliance then, merely that the work will be "reasonably safe."

We know that many local authorities have taken it upon themselves to declare that everything must be to the current BS7671 for them to accept it, even though the guidelines in the government's own approved document clearly state that other standards are deemed to be in compliance.

Well of course they do - that's how regulations work. They are not "insisting that anything installed new has to comply with the current rules" because they are jobsworths, or because they can't think, or because they belong to a scheme, they are insisting on it because it is what the regulations insist on.

But as you've acknowledged yourself, those regulations are not regulations with any sort of legal status (other than government guidelines which indicate that complying with them will be deemed to be compliance with the "reasonably safe" provision). They are the rules set out by one particular institution, be it an influential one, and followed by the general electrical trade in Britain. There is nothing, legally, to stop an electrician from deviating from them if he feels it better serves his customer, that a rule is inappropriate to a particular situation, etc.

I don't think that any sane person would ever suggest that sort of thing. And it's hard to see how any changes/updates/renewals/etc could be mandated without changing the status of BS 7671, which for some reason they don't want to do.

That was another rather curious aspect surrounding the whole introduction of Part P. Certainly I do not feel that it would be either necessary or desirable to have BS7671 in its current form imposed on installations, but given just how ingrained it is in the British electrical trade, I do wonder why the government didn't specify that it would become the required legal standard, in a similar way to that in which the NEC is adopted into state laws here.

Perhaps it was a case of not wanting to stipulate a particular British Standard given the way that official regulations in the U.K. have been moving more and more toward those "harmonized" European standards in recent years. The guidelines in the approved document certainly hint at that, given that they recognize the equivalent wiring standards of any other EU/EEA country as being acceptable.

Maybe the long-term plan was to wait until such time as a single "Euro-Norm" set of wiring regulations is published for the whole of the EU, then bring that into the statutes as the legally required standard?