Tom,
Just for clarity.
If you check, I didn't mention any BS's, I quoted the RRFSO, then there is CDM to consider, both of which are law.
If the layout of the building and the design of the fire alarm system increases the danger to persons, then it's likely a breach of law, regardless of what any BS says.
Then there are building regulations, which again are law, and they also, as it happens, guide readers for advice on compliance to the BS's.
As HSE do with their HSR25 document guiding readers to BS 7671 for guidance on meeting the requirements of EAWR.
So, whilst not law, I agree, the BS's would after the breach of law has been established, likely used as an assistant document to add weight to the prosecution, to illustrate how the duty holder failed in their legal responsibilities, and to illustrate that if they had followed the guidance then the situation likely would not have occurred.
So again, until now, I have not mentioned any British Standards, if you look at my first post I cite RRFSO.
I will repeat what I said earlier though.
The normalisation of deviance is not acceptable, and must be challenged to save lives, prevent injury to persons and damage to property.
Just because it's the norm, does not make it right.
Eventually the rules will change.
Just an example, the requirement for resistance of premature collapse of wiring systems has been a requirement since CDM first became law in 2007, however, it won't be fully implemented into BS 7671 until January 1st 2019.
It's only had to be brought into BS 7671 because it was being ignored, and it killed people.