49 CFR §192.471

1. (a)Each test lead wire must be connected to the pipeline so as to remain mechanically secure and electrically conductive.
2. (b)Each test lead wire must be attached to the pipeline so as to minimize stress concentration on the pipe.
3. (c)Each bared test lead wire and bared metallic area at point of connection to the pipeline must be coated with an electrical insulating material compatible with the pipe coating and the insulation on the wire.