The first steps of this lesson
Step 1: Why the clear space exists
8 CCR §2340.16(a): sufficient access and working space shall be provided and maintained about all electric equipment to permit ready and safe operation and maintenance. The detailed dimensions in §2340.16(b) apply to equipment likely to require examination, adjustment, servicing or maintenance while energized. Under (c), working space shall not be used for storage, and when normally enclosed live parts are exposed for inspection or servicing in a passageway or general open space the space must be suitably guarded.
Step 2: Depth: Table 2340.16 and the CFC floor
§2340.16(b)(1): the depth of the working space in the direction of access to live parts shall not be less than the minimum in Table 2340.16 (600 V or less), measured from the live parts if exposed or from the enclosure front or opening if enclosed. The table is entered by Condition 1 (live parts on one side, nothing live or grounded on the other), Condition 2 (live parts on one side, grounded parts on the other; concrete, brick or tile counts as grounded) or Condition 3 (live parts on both sides with the operator between). Exception 1 allows 2.5 ft for installations built before April 16, 1981. The 2025 California Fire Code §603.4 separately requires, in front of electrical service equipment, working space not less than 30 inches wide, 36 inches deep and 78 inches high, and the width is not less than the equipment width if it is wider than 30 inches. Note: the numeric rows of Table 2340.16 are not reproduced in the text copy used for this lesson, so the worked example uses the 36 in printed in CFC §603.4.
The remaining 3 steps, the worked example and the quiz are in the course. This is a preview. The full lesson, with the step-by-step explanations, a worked example and a quick-check quiz, is inside the classroom.
Independent exam preparation. Contractors Classroom is not affiliated with the Contractors State License Board, and no course can guarantee a passing result.