NESC Line Relations: Clarifying Section 220.B.2.b

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Section 220.B.2.b of the NESC specifies that supply circuits must be positioned on the end and adjacent pins of the lowest support arm, with a required climbing space of 750 mm (30 in) from the ground to at least 600 mm (24 in) above the circuits. This regulation applies to supply lines of 600V or less and under 5kW on structures that also support other line classes. The term "climbing space" refers to the area left clear for maintenance workers to safely ascend the pole. There is uncertainty about whether the climbing space measurement should start from the ground conductor, but this interpretation lacks clear justification within the code. Clarification on these points is sought to ensure compliance with the NESC standards.
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I have a question about a confusing section of the NESC (not that many sections are not confusing, but this is my current issue).

Section 220.B.2.b reads as follows
That the supply circuits be placed on the end and adjacent pins of the lowest through signal
support arm and that a 750 mm (30 in) climbing space be maintained from the ground
up to a point at least 600 mm (24 in) above the supply circuits. The supply circuits shall be
rendered conspicuous by the use of insulators of different form or color from others on the
pole line or by stenciling the voltage on each side of the support arm between the pins carrying each supply circuit, or by indicating the voltage by means of metal characters.

This section has to do with supply lines of 600V or less and carrying less than 5kW coming to a support structure carrying other classes of lines. I believe there is a word missing, but can't prove it.

The confusion, at least for me, is the 30 climing space from ground. I suspect that must be the ground CONDUCTOR, but since the code is notoriously anal about its application, I can't justify that thought. Can somone provide some clarification?

Thanks.
 
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Ping @Tom.G can you make sense of this spring clean post? I don't understand the phrase "climbing space".
 
The space left open for a worker to climb the pole to do maintenance.
 
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