Fire stopping is the process used to seal all fire rated penetrations (Plumbing, Electric, Mechanical, Sprinklers, and Low-Voltage) going through fire rated walls of commercial/ residential buildings using U.L. products that have been tested and approved. The purpose of fire stopping is to contain the origin of fire and smoke within its area to allow enough time to evacuate and allow the building to maintain its integrity for a longer period of time which can vary based on the product and U.L. system being used.