What does BX commonly refer to in electrical wiring?

BX commonly refers to insulated wires that are covered with flexible steel armor. This type of cable is also known as armored cable and is designed to provide both mechanical protection and a degree of fire resistance. The outer metal sheath protects the insulated conductors within, making BX cable suitable for various installations, particularly in areas where additional protection is necessary due to environmental concerns or potential physical damage. The insulation around the conductors helps prevent electrical shorts and protects users from electrical shock.

The other options do not accurately describe BX wiring. Uninsulated wires are not associated with BX, as BX specifically includes insulated conductors. Wires made of aluminum fall into a different category of wiring and are not what BX refers to. High-voltage wires, while they may also be armored, involve different specifications and uses that do not align with the characteristics of BX. Understanding the specific features of BX and its applications is essential for safe and effective electrical work.