Standards used for indoor telephone cabling?
The usual source is TIA/EIA-568, which also describes the cat5e and cat6
cables used for Ethernet.  I believe normal house wiring is cat3 under
that standard.

I'm not sure 'PE' (does that mean polyethylene?) is a specified insulator or sheathing material, though.   There are both PVC and other (plenum-rated) sheathing materials for cat5, so the standard is unlikely to be very specific.