Services & DistributionQuestion 53 of 521
What is the minimum depth of working space in front of a 120/240 V panelboard (Condition 1, exposed live parts on one side)?
a.2 ft (0.6 m)
b.4 ft (1.2 m)
c.3.5 ft (1.07 m)
d.3 ft (0.9 m)
Explanation
Per Table 110.26(A)(1), Condition 1 for systems 0-150 V to ground requires 3 ft (900 mm) of clear working depth. 2 ft is too shallow, and 3.5 ft/4 ft apply to higher-voltage or Condition 2/3 situations.
Law Reference: 2023 NEC §110.26Practice all 521 questions free — no signup required.
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