In box fill calculations, how are equipment grounding conductors counted?

• A. They count as a single conductor regardless of number.
• B. Each equipment grounding conductor is counted separately.
• C. They are excluded from box fill calculations.
• D. They count as two conductors if there are two or more.

Answer: (A)

In box fill calculations, equipment grounding conductors are counted as a single conductor, no matter how many there are. This follows the NEC rule that all grounding conductors in a box together count as one conductor for fill purposes. The volume used for that one conductor is based on the largest grounding conductor present in the box. So if you have several grounding conductors of different sizes, you still count them as one conductor, using the size of the largest one to determine cubic inches. For example, if the box contains grounding conductors of 14 AWG, 12 AWG, and 8 AWG, you count them as one conductor and use the volume of an 8 AWG conductor to determine the box’s cubic inch requirement.