Which material is commonly used for providing firestop seals for cable penetrations?

In the context of providing firestop seals for cable penetrations, pillows are specifically designed to block fire and smoke from passing through openings around cables. They are made from fire-resistant materials and typically conform to the shapes of the penetrations, allowing for effective sealing.

Pillows offer the advantage of being easily removable or replaceable, which is beneficial in applications where cables may need to be added or changed over time. Their flexibility allows them to adapt to different cable configurations, ensuring that they maintain a proper seal while adhering to fire safety codes and regulations.

While other materials like foams, mortars, and caulk can also be used for firestop applications, they serve different purposes and may not provide the same level of adaptability as pillows when dealing with penetrations that need to accommodate changes or additions of cabling. Foams might be better suited for specific areas but may not have the same versatility, and mortars and caulks often imply a more permanent solution that could complicate future modifications. Thus, pillows stand out for their combination of fire protection and practical usability in cable penetrations.