Danc,
Welcome to ECN, mate!.
Glad to have you along.
Glenn(safetygem), good comments, I have to say, that if us Linemen didn't have rubber we'd have to pack up and go home.
Danc,
Please bear in mind that insulated matting is just one part of a whole PPE system.
I use mats at work with the PoCo here in NZ and it's written in our safety rules that gloves(Insulated) and visor needs to be worn as well.