In what situation is it necessary to use a conduit?

Using a conduit is particularly necessary when running wiring on the surface or through walls for several reasons. Conduit serves as a protective pathway for electrical wires, safeguarding them from physical damage, moisture, and corrosive elements that might be present in the environment. This is especially important in situations where the wiring could be exposed to wear and tear or where building codes require additional layers of protection.

In areas where wiring is run through walls, conduit not only protects the wiring but also organizes it, making it easier to replace or add wiring in the future. This can be crucial in avoiding fire hazards or electrical problems that may arise from improperly installed or damaged wiring.

In contrast, installing residential light fixtures, connecting outlets in a room, or installing switches usually involves the use of wire that is already in a protected form and does not necessitate the additional protection of conduit unless specified by local codes or if the installation is in an area deemed hazardous.