Which type of environment restricts the use of standard NM cable?

The correct answer is wet environments because NM (non-metallic) cable, commonly known as Romex, is not rated for use in locations where it may be exposed to moisture or wet conditions. Wet environments can include areas where the wiring may be in contact with water, such as outdoor installations, areas prone to flooding, or locations like basements that can experience high humidity or standing water.

Using NM cable in such situations could lead to serious safety hazards, including electrical shock or fire risk, as the cable is not designed to withstand moisture, which can degrade insulation and lead to potential short circuits.

On the other hand, while standard NM cable can be used in dry environments, corrosive environments pose risks as well, though the concern is more about the materials used in the cables facing chemical reactions than moisture. Similarly, low temperature environments do not restrict the use of NM cable, as it can perform adequately at lower temperatures. Understanding the proper applications for NM cable helps ensure both the safety and functionality of electrical installations.