What is the annular space in relation to firestopping?

The annular space refers specifically to the gap or distance between a penetrant, such as a pipe, conduit, or cable, and the edges of the opening through which it passes in a fire-rated assembly. This space is critical when considering firestopping measures because it is where firestop materials are applied to prevent the spread of smoke, flames, and heat through the opening. Properly filling this space with an appropriate firestop material is essential to maintaining the integrity of fire-rated walls and floors, thereby contributing to the overall fire protection strategy of a building.

Understanding this concept is crucial for anyone involved in firestop applications, as it emphasizes the importance of ensuring that all gaps around penetrants are effectively sealed to meet life safety and building code requirements.