What is the maximum voltage permitted between conductors supplying screw shell lampholders in dwelling occupancies?

The maximum voltage permitted between conductors supplying screw shell lampholders in dwelling occupancies is 120 volts. This standard is based on safety considerations, ensuring that residential lighting fixtures pose a minimal risk of electric shock or electrical fires. In most residential applications, lighting circuits are designed to operate on a standard voltage of 120 volts, which aligns with the voltage ratings of common household equipment and fixtures.

Choosing a voltage higher than this in dwelling areas would increase the risk of hazards without any significant advantages, given that the primary function of lighting fixtures is to provide illumination safely and efficiently within homes. Therefore, the specification of 120 volts aligns with both practical applications and safety codes, making it the correct and widely accepted choice for these installations.