Firestopping - What is it?

According to the wiki, "A firestop is a passive fire protection system of various components used to seal openings and joints in fire-resistance rated wall and/or floor assemblies, based on fire testing and certification listsings.

In other words, a Passive Fire Protection System works to slow the spread of fire and smoke through a building with the use of fire and smoke barriers to compartmentalize and contain the fire to a specific area. Those barriers can be fire rated walls, ceilings, and floors (for example) and they must be maintained to ensure the integrity of the Life Safety Fire Protection System of a building. The fire doors that seal the walls and the fire dampers that enclose the ductwork going through the walls and floors need inspection to ensure they are working properly on a regular basis. The firestopping that seals the unprotected openings and penetrations that go through the barriers all must be maintained as well.