What aspect must wiring methods meet to be included in the National Electrical Code?

Wiring methods included in the National Electrical Code (NEC) must meet the aspect of suitability. Suitability refers to the appropriateness and acceptability of the wiring methods for the specific applications they are intended for. This entails that the materials and methods used must be compatible with the conditions they will operate in, which can encompass factors such as the environment, electrical load, and installation practices.

The NEC outlines specific requirements to ensure that electrical installations are safe, reliable, and effective for the intended use. By emphasizing suitability, the NEC ensures that wiring methods can handle the electrical loads they will encounter, resist environmental factors, and comply with safety standards. This focus is critical because using wiring methods that are not suitable for a particular application can lead to safety hazards such as overheating, electrical failures, or fires.

Cost-effectiveness, while an important consideration in construction and installation, is not a primary criterion for inclusion in the NEC. Similarly, durability and efficiency are desirable attributes but do not fully encapsulate the main requirement of suitability as it relates to specific application standards outlined in the code.