800+ Plastic KMF switches or Plastic cased fused isolators being used to protected tails feeding CU over 8m away. Idea was new connected meter, tailed into KMF then onto CU. Has been flagged that KMFs are plastic therefore cannot be connected to, Meter company want to install additional DP isolator then sparks to attach from that to KMF. However also in the meter box will be all equipment associated with solar panels simply know room. Now if the meter box was deemed as a non-combustible enclosure the KMFs are fine how are they classed? Anyone have any input?