Late contributor and, no, I am afraid I haven't read through this entire thread, its far too long, but I just wanted to add how I view this new measure and how it should be treated.
Lets just assess this for one moment. The current manufacturing standard for consumer units is not considered good enough for containing a fire. In order to improve on this it has been decided to introduce a better consumer unit that will be capable of containing a fire. That is all I see it as, tbh. It doesn't mean that post Jan 2016 all old style CUs become C2 (or C3) on an EICR, in my opinion, but no doubt many will see the need to code it. But read on. Electricians conveniently forget that regs are NOT retrospective. All it means as far as I am concerned in this case is that post Jan 2016 we are required to install an
improved item of equipment that GOING FORWARD will improve fire safety issues attributed to CUs . Taking out existing CUs because they are not the improved model is quite frankly daft. Fire-rating has nothing to do with ELECTRICAL safety. Its not like adding a 30mA RCD to a circuit, for example, this improves safety from electrical hazards. Improving the fire rating integrity of a CU is nothing to do with electrical safety it is moving in to the realms of Part B fire safety. If you approach the situation from that angle it helps to rationalise what is going to happen. I think the trade organisations need to properly consider how the improved CUs should be handled because at the minute I am already seeing the implementation of the improved CUs as a retrospective reason to code current CUs which plainly is not as it should be. [

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