General Order 64-A

Section XI

Supply Lines And Communication Lines Crossings Over Railways

112.1    Duplex Pin Construction.

Where this type of construction is used at railroad crossings, a guard arm of at least the length of the longest duplex arm shall be placed not less than 6 inches below the lowest duplex arm except where an arm supporting other than duplex construction is used in lieu thereof.

In addition, the corresponding ends of all duplex arms and the guard arm shall be so connected as to further prevent any of the conductors from falling into the grossing.