What rating must through penetrations in fire-resistance-rated walls have when protected?

Through penetrations in fire-resistance-rated walls must have an F rating when protected. This rating indicates that the firestop system in place effectively maintains the wall's fire-resistance integrity. Fire-resistance-rated walls are designed to limit the spread of fire and smoke between different spaces in a building, and any penetrations, such as pipes or electrical conduits, can compromise this rating if not properly protected.

The F rating specifically assesses the ability of these firestop systems to prevent the passage of flames and hot gases through the penetration, serving as a crucial measure to ensure that the overall fire-resistance performance of the wall is upheld. Therefore, to maintain safety and compliance with fire protection standards, it's essential for through penetrations to be rated appropriately with an F rating, ensuring fire safety in commercial buildings.