In electrical wiring, what is a general NEC expectation regarding conductors?

• A. All wires must be insulated
• B. All wires must be bare
• C. Wiring insulation is optional
• D. Conductor insulation is prohibited

Answer: (A)

In most electrical systems, keeping conductors insulated is essential for safety and proper operation. Insulation protects people from shock, prevents accidental contact with live parts, and shields conductors from moisture, abrasion, and environmental damage. It also allows conductors to be routed through walls, ceilings, and equipment without risk of shorts or arcing, and enables color coding to identify hot, neutral, and ground paths.

That’s why the general NEC expectation is that conductors are insulated. Bare conductors are not the norm for typical circuits because they create serious shock and short‑circuit hazards. The statement that insulation is optional or prohibited would ignore the safety protections insulation provides. The only common exception is that equipment grounding conductors can be bare in many installations, but this is not the general rule for all conductors.