What is the column web depth limit when a primer is beneath SFRM?

The column web depth limit when a primer is beneath Spray-Applied Fire-Resistive Material (SFRM) is 16 inches. This limit is established based on considerations regarding the effective performance and adherence of the SFRM. When the web depth is within this limit, the spray-applied material can adequately bond and provide the necessary fire resistance, ensuring that the structural integrity of the column is maintained under fire exposure conditions.

Understanding this specific depth limit is crucial for proper installation and compliance with safety standards. If the web depth exceeds this limit, the performance of the fireproofing might be compromised, leading to an increased risk of steel member exposure to high temperatures during a fire event. Therefore, adhering to the 16-inch limit is essential for ensuring that fireproofing meets both code requirements and provides effective thermal protection for structural steel elements.