I thought of this because the other day i cleaned on a new build estate, the house i was about to clean had overhead power cables not far away. I mean proper power cables on pylons, they were clearly insulated and i estimated the top of my pole was maybe 10m away at most. It was an overcast damp day and i just decided to not do them, i had cleaned that house 3 times before and never really noticed them but for some reason the other day i did and they made me nervous enough to just leave it.
I think if theres to be any education it should be on how to spot a live cable because apart from the obvious ones sometimes its a guess, i clean near a few thin cables that ive always assumed are telephone wires and not dangerous but in reality i dont know for sure .
Always best to act on the side of caution.
If there are 3 supply cables then usually the bottom cable is earth and the others are positive and negative. They will be normal household supply voltage, but still to be very weary of.
At one time we had overhead powerlines supplying an area with high voltage wiring. The electricity board replaced that section we were concerned cleaning around with abc cables which are twisted together.
Any cable connected to a telephone pole isn't an issue but still need to be treated with respect. I'm not sure what's happening now, but suddenly there are cables being added to telephone poles for broad band. I don't know if the old cables will be removed over time. We have a business customer who now has two new cables running right in front of an upstairs window we clean.