Section E3405 requires protection of electrical wiring from physical damage. Romex cables in unfinished basements must be protected where subject to physical damage, typically by raceways or conduit in high-traffic areas. Cables run across floor must be protected by conduit. Cables in walls must avoid contact with nails and screws, typically by positioning in the center of studs or by protection plates. Low-voltage circuits (telephone, TV, internet) must be separated from high-voltage circuits to prevent interference.