Fair enough. As an engineer, I too am expected to make evidence based judgements, or present evidence to colleagues who have to make a decision.
I'm pleased to hear that - and one might hope that would mean that you would share some of my concerns about things which appear to be minimally 'evidence-based'.
You seem to be applying the same flawed logic that the vendors of these so called safety covers use - that they prevent a risk.
Not at all. In the absence of any hard evidence (or either harm or benefit), I'm just remaining 'open-minded' - I'm certainly not dismissing the claims that they result in some risks (since they undoubtedly do to at least some extent), but nor am I dismissing the possibility that they might also sometimes reduce or prevent risks. I just don't know (and certainly don't know about the balance between the pros and cons), and I would perhaps have expected you to feel the same, given your experience of 'evidence-based' decisions.
I would imagine that would be heard to come by. The main problem is that the general public aren't likely to report anything, and the authorities are only likely to know if it's serious (e.g. someone is hospitalised.) Also, some of the potential harms would not be related to the previous (possibly years previous) use of these items.
Evidence (for either causation or reduction/prevention of harm) would certainly be very difficult to 'come by' - but, if one believed in evidence-based decisions, difficulty in finding evidence is not really, in itself, reason to jump in one direction on the basis of one's theeory-based opinion.
I think you are more generous to the manufacturers than I am. .... I am really sceptical that someone looked at the standard and consciously designed something with larger pins.
You are quite possibly right. However, again I just don't know - so if you want to go with your own opinions rather than anything based on facts, then I suppose that is your prerogative.
As I've recently written, I think we're now seeing similar with SPDs (with maybe AFDs/whatever 'to come'). Some people seem to be totally sold on the idea that they are 'necessary', seemingly almost totally because of theory-based opinions - despite the paucity of any evidence I've managed to find (and I've looked quite hard) that there is actually a significant 'need' for them.
Agreed. Either that, or the requirement should specify what standard it is required to meet - e.g. by referencing an existing standard for flammability.
Sure, the reference to 'non-combustible' is quite ridiculous and those who wrote it should have known better - as you imply, they obviously should have clearly defined what degree of 'flammability' is required.
However, that's not the main problem with that reg - more important is the lack of significant evidence (that I've seen or heard of) that there is/was a significant need for some higher degree of 'fire resistance' of CU enclosures - particularly given that metal CUs etc.
do introduce some dangers.
Unfortunately, we seem to be getting ignored as there's been no shortage of people (myself included) who have raised this - yet there's been, IIRC, 2 or 3 new versions where they've failed to fix this f'up that brings BS7671 and BSI into disrepute.
Rumour had it that it was intense pressure/'threats' from LFB that resulted in the appearance of the reg in the first place - so I suppose the same may be resisting any modification to it?
