To limit the free passage of smoke, what must fill the space around a duct penetrating a smoke partition?

To effectively limit the free passage of smoke around a duct that penetrates a smoke partition, it is essential to use approved materials specifically designed for this purpose. Smoke partitions are critical components of a building's fire protection strategy, as they help contain smoke within certain areas, enhancing safety and facilitating evacuation during a fire incident.

The use of approved materials ensures that there is a proper sealing mechanism in place that meets fire and safety codes, thus minimizing smoke migration through the penetration. These materials are often tested for their smoke and fire resistance capabilities, thereby contributing to the overall integrity of the smoke partition.

Using materials that are not specifically approved for this application, such as air or insulation alone, may not provide the necessary protection against smoke passage. Similarly, plastic sheeting, while it might offer some level of obstruction, typically does not meet the stringent requirements mandated to ensure fire safety in commercial buildings. Hence, utilizing approved material is critical for maintaining the effectiveness of smoke partitions during emergencies.