General Order 64
Section IV
General Clearance Requirements – All Classes Of Lines
44 Lateral Working Space (See Appendix E, Fig. 11)
(a) Height of Working Space: The lateral working space between supply conductors and between supply and signal conductors shall have an approximate vertical height of not less than that given in Table 2.
(b) Width of Working Space: This space on the climbing side of the pole extends laterally from each side of the climbing space to the outer pin position of the arm and with a minimum horizontal width from the face of the crossarm equal to the width of the climbing space required fro the highest voltage conductor concerned.
(c) Freedom of Obstruction: No vertical or lateral conductors shall obstruct this working space. Such conductors, if not on the opposite side of the pole from the climbing side, must be at least as far from the crossarms as the width of the climbing space required for the highest voltage conductors concerned.