Which NEC section requires firestopping of electrical penetrations?

• A. 300.21
• B. 310.15
• C. 200.1
• D. 400.8

Answer: (A)

Firestop requirements come into play whenever electrical cables, conduits, or other penetrations pass through fire-rated walls or floors. The goal is to maintain the fire-resistance rating of the assembly by sealing around those openings with listed firestop materials. The NEC section that directly addresses openings through fire barriers and the need for proper fireproof sealing around electrical penetrations is the one that best fits this concept. It specifically requires firestop protection to preserve the integrity of the barrier. The other sections focus on different topics: ampacity of conductors (not firestopping), general scope for wiring within Article 200, and the use of flexible cords (not firestop requirements).