A duct and air transfer openings that penetrate a ceiling membrane of a fire-resistance rated assembly must be protected with what?

In the context of fire-resistance rated assemblies, the protection of duct and air transfer openings that penetrate a ceiling membrane is crucial for maintaining the integrity of the fire-rated barrier. This is necessary to prevent the spread of fire and smoke between different areas of a building, particularly when different occupancy types are adjacent to each other.

A fire damper serves to close off ducts when a fire is detected, stopping the flow of smoke and preventing the spread of flames through spaces that ducts may connect. This is especially important in maintaining the fire-resistance rating of the assembly.

A ceiling radiation damper is specifically designed for openings that are created in a ceiling to allow for the passage of ducts. It is designed to close automatically when a certain temperature is reached, helping to control the transfer of heat and possibly flame through the ceiling assembly.

A shaft enclosure provides a more extensive level of protection for vertical ducts in multi-story buildings by creating a fire-rated pathway that can contain fire and smoke for a specified duration, typically fulfilling fire safety regulations.

Since all these devices serve to protect openings and maintain the integrity of fire-resistance rated assemblies in different situations and scenarios, the correct answer indicates that all of the listed options play a vital role in ensuring adequate fire safety measures are implemented