How are grounds counted in box fill?

All equipment grounds combined usually count as one conductor volume based on the largest ground conductor in the box.

How are devices counted?

Each yoke device typically counts as two conductor volumes of the largest conductor connected to that device.

Quick NEC 314.16 style check of required vs. actual box volume.

Conductor Size

Insulated Conductors

Device Yokes

Internal Clamps Present?

All Grounds Present?

Actual Box Volume (in³)

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