Fire stops are materials or systems used to prevent the spread of fire and smoke through openings in walls, floors, and ceilings. They are essential in maintaining the integrity of fire-rated assemblies, which are designed to resist fire for a specific period. Common fire stop materials include fire-resistant caulk, intumescent sealants, and fire stop blocks. These systems are installed around penetrations, such as pipes and electrical conduits, to seal gaps and openings. Proper installation of fire stops is crucial for building safety, as they help protect occupants and property by slowing down the movement of flames and smoke during a fire incident.