NESC Part 1 vs Part 2 1

I am looking for a general consensus of where part 1 of the NESC stops and part 2 starts. I understand the basics of part one is for substations and equipment and part 2 is for Overhead electric and commo lines. The last sentence under the "Scope" portion of the title states that part 1, "It also covers the conductor and equipment employed primarily for the utilization of electric power when such conductors and equipment are used by the utility in the exercise of its functions as a utility." This speaks to the use of conductors and etc, so could this be applied in the circuit level design of a distribution system? Thanks for any input.