Still not quite correct Matt.
At that time the DPC stated that 960 deg glow wire tested material would be acceptable.
Some manufacturers will still be selling plastic CU's even after the change in regulations as they believe that their plastic material meets the requirement and, intent of the regulation.
There is still no reason for there not to be a plastic material that meets the flammability requirement of the intent of this regulation.
Not all CU's will be steel, and not all will have to be, the requirement is only that those in dwellings, and attached outbuildings are "non flammable".
A plastic CU will still be acceptable, and allowed, if it is mounted within a "fire proof" enclosure, so a steel box over the outside, or say double plasterboarded box around the unit.
This reg is delayed until Jan 2016.
What I find most disturbing is the reason LFB pushed for this is simply due to incompetent installation practices.
It is so sad that the rest of Europe have no need for this requirement.
It is also BEAMA & their member companies who have pushed the steel bit through it seems, noting that BEAMA also have representation on JPEL/64.
There is nothing to stop a Corrigendum at any point, allowing the use of another material, if one becomes used by a manufacturer and offers a benefit.
It is a shame that this has been allowed to happen IMHO.
There is no need for it.
Also, talking to manufacturers representatives, and looking at one of the proposed units, it was certainly ill conceived in some aspects.
A big as yet unanswered question is about cable terminations into the steel enclosures.
