Direct-buried conductors subject to movement by settlement or frost shall be arranged to prevent damage to what?

• A. Insulation
• B. Enclosed conductors
• C. Joints
• D. Terminals

Answer: (B)

When underground wiring can move because the soil settles or freezes, the risk is that that movement will put stress on nearby conductors that are housed in protective enclosures. The rule is to arrange direct-buried conductors in a way that prevents damage to those enclosed conductors, since the enclosure contains conductors that are already protected by a barrier and are more vulnerable to being compromised by shifting cables nearby. By spacing or routing the buried conductors so they don’t rub or strike into the enclosures, you keep the integrity of the enclosed conductors intact and reduce the chance of insulation wear, shorts, or other faults that could affect the system.

Insulation, joints, and terminals are important components, but the requirement specifically targets preventing damage to conductors that are enclosed within raceways or enclosures, where movement could propagate harm to the protected conductors inside.