General Order 64-A

Section XII

Supply Lines And Communication Lines Under Structures

121.1    Clearances.

The clearances to be observed are given in Section III, Table 1, Case 9, referring particularly to the clearances to be observed from wires to a bridge structure.  The clearances of the wires above the ground are also given in Table 1, Cases 1 to 5 inclusive.

A.    Cable or Conduit.

Where the clearances required in Section III for open wires can not be obtained, the crossing may be made in cable or conduit.