Which of the following is NOT a common material used in firestop systems?

The identification of gypsum board as not being a common material specifically used in firestop systems is accurate because gypsum board is primarily utilized as a construction material for walls and ceilings, providing fire resistance and structural integrity. While it does possess fire-resistant properties, its main function is as a substrate rather than a firestop component.

In firestop systems, materials like intumescent seals, firestop caulk, and firestop collars are specifically designed to prevent the spread of fire, smoke, and heat through openings in fire-rated walls, floors, and ceilings. Intumescent seals, for example, expand when exposed to heat, filling gaps and creating a barrier against fire. Firestop caulk is formulated to seal penetrations and joints, effectively containing fires in their origin. Firestop collars are devices used to protect plastic pipes, expanding during a fire to close off the opening and prevent the passage of flames.

While gypsum board can contribute to the overall fire-resistance rating of a building, it does not serve the same specific purpose and function as the other materials listed, which are integral components of firestop systems.