What is the minimum cubic inch volume required for a two-gang box that contains specific NM cables and clamps?

To determine the minimum cubic inch volume required for a two-gang box containing specific NM cables and clamps, one must consider the various factors that contribute to box fill calculations.

The National Electrical Code (NEC) provides guidelines for calculating the box fill based on the conductors, clamps, and devices that will be housed within the box. For a two-gang box, the volume must accommodate not only the wires but also the space needed for the clamps and any other devices being installed. Each conductor has a specific volume allowance based on its size and type, and the clamps also require additional space.

In this scenario, the combination of the number of NM cables and clamps dictates that the box must have a minimum volume of 30 cubic inches. This value provides enough space for all the conductors and clamps while adhering to the code requirements. Insufficient box volume may lead to overcrowding, which can increase the risk of overheating and potential fire hazards. Therefore, the choice of 30 cubic inches ensures compliance with safety standards, allowing for proper installation and operation of the electrical system.