What are firestop pillows, and when are they typically used?

Firestop pillows are designed as soft, compressible materials that provide firestopping capabilities for temporary or flexible penetrations within fire-rated assemblies. They are often used in applications that require easy installation and removal, such as when cables, conduits, or other services pass through walls, floors, or ceilings.

The flexibility of firestop pillows allows them to adapt to various sizes of penetrations and different types of penetrant materials, ensuring a reliable seal against the passage of fire, smoke, and hot gases. They can be placed around these penetrations as a preventive measure in buildings to maintain the integrity of fire-resistance-rated constructions.

In contrast, hard materials or rigid blocks typically relate to permanent firestop systems that are used in conjunction with structural elements. Sealants, while also important firestopping materials, serve different purposes primarily focused on sealing joints rather than filling flexible penetrations. Therefore, the defining characteristics of firestop pillows as soft, adaptable materials clearly align with their correct identification and typical applications.