Which type of wiring is most suitable for exposed locations at risk of mechanical damage?

In exposed locations where there is a significant risk of mechanical damage, flexible metal conduit commonly known as BX is the most suitable choice. BX features a flexible metal sheath that provides excellent protection against physical impacts, making it ideal for environments where wiring may be susceptible to being bumped or otherwise damaged.

BX wiring allows for movement and adjustments without compromising the integrity of the conductors inside, which is particularly valuable in applications where wiring runs may be in proximity to activities that pose potential hazards. The metal covering also adds an additional layer of safety by providing grounding, further enhancing the overall protection of the electrical system.

While Romex is often used for residential wiring, it is not designed for exposed applications where mechanical damage is a concern as it has a plastic outer sheath and lacks the robustness of metal sheath options. MC Cable, while also providing some protection, is typically not as flexible as BX and may not perform as well in highly exposed situations. Circuitry refers to a broad category of wiring and does not address the specific requirements or protections needed for exposed wiring in potentially hazardous locations. Therefore, BX is the optimum selection for addressing the risks associated with mechanical damage.