On 05/08/15 22:31, Andrew Gabriel wrote:

Double insulated kits have been available for some metal CU's for years.
They basically provide an extra plastic layer to insulate the incomer
cables/connections through to the RCD.


Technically the tails are already double insulated. So this would be
"triple insulation"?

But there would be something to be said for a plastic sub enclosure in
all CUs to fully separate the incomer from the final circuits.