There are appropriate boom type lifts with 'glass inserts in the boom section(s) that effectivly insulate the platform & operator...but that rental item has to be searched for. The rental companies are very CYA about using the equipment properly, all the legaleese is within the rental documentation. Maintaining clearances from electrical lines is probably mentioned many, many times.
A scissor lift theoretically is 'insulated' by virtue of the tires; but yes, contact with a grounded object can be a problem.
There are boom trucks with steel booms, with the basket mounted via insulators.
I owned a bucket truck, 55' TECO, end hung, with 'glass inserts in the lower & upper boom sections. Certified and tested to 35KV.
Bottom line is, maintaining clearances from conductors, and maintaining a non-conductive path to earth. Using a device that is 'non'grounded' via tires is only good IF there is no contact between the earth and the device by a person touching the device. (That's one of the many safety decals)
On the same note, using a 'glass ladder and coming into contact with a live item, and another conductive item.....the 'glass don't help. Training, concentration, and common sense rule!
