What is the minimum box volume requirement for two 12 AWG conductors passing unbroken through a lighting outlet box?

To determine the minimum box volume requirement for two 12 AWG conductors passing unbroken through a lighting outlet box, it is essential to understand the factors that contribute to the volume calculation for electrical boxes.

According to the National Electrical Code (NEC), a certain volume is allocated for each conductor entering a box. For 12 AWG conductors, each wire requires a volume of at least 2 cubic inches. In addition to the volume for the conductors, the box must also accommodate additional space for any devices or connections. For a lighting outlet box, if we consider only the conductors, two 12 AWG conductors would necessitate a base volume of 4 cubic inches (2 inches per conductor).

Furthermore, the volume must account for any equipment being installed, such as a switch or fixture, which typically requires an additional minimum volume of 12 cubic inches. This leads to a total calculation of at least 16 cubic inches for the conductors and devices in the box.

When considering option B, which states 16 in.³, this is indeed the minimum volume required to safely and adequately house the two conductors while allowing for additional connections. Therefore, this option meets the NEC requirements for a lighting outlet box with two