Which of the following factors does not affect the allowable number of conductors in a box according to NEC?

The allowable number of conductors in a box is determined by several key factors related to safety, heat dissipation, and space considerations in electrical installations. Among these factors, the gauge of the conductors impacts the overall fill calculations because different gauges have different physical sizes and take up varying amounts of space within the box. The dimensions of the box itself are critical, as larger boxes can accommodate more conductors than smaller ones, in accordance with the rules outlined in the National Electrical Code (NEC).

The installation environment plays a role as well, influencing considerations such as heat dissipation and potential physical damage. For example, conductors installed in a damp or wet location may require different handling than those in a dry location. These environmental factors can therefore affect the allowable number of conductors due to cautionary measures taken for safety and equipment longevity.

In contrast, the type of raceway does not influence the allowable number of conductors in a box according to the NEC. While raceway type can affect other installation practices or the protection of conductors, it does not directly determine how many conductors can be safely housed within a box. Thus, it is not a factor in the calculations for box fill, making it the correct choice for this question.