How many SFRM thickness tests are required underneath metal decking that is 6,500 square feet?

The requirement for the number of SFRM (Spray-Applied Fire-Resistive Material) thickness tests is typically based on the area of application and specific codes or standards that govern fireproofing installations. In many guidelines, such as those outlined by the International Building Code (IBC) or other relevant standards, a systematic approach to testing ensures that the application meets the required fire-resistance rating throughout the entire surface area.

For an area of 6,500 square feet, the prescribed testing procedures usually involve conducting thickness tests at specific intervals to adequately represent the entire surface. The decision to select 7 tests in this case aligns with the common practice of establishing a testing frequency that ensures quality and compliance across the entire installation. The number of tests can be determined by a formula or rule of thumb that takes into account the square footage, allowing inspectors to verify that the applied fireproofing maintains consistent thickness for effective fire resistance.

This method ensures that hot spots or areas where the application may not have met the specified thickness are identified and addressed, ultimately leading to a safer and more code-compliant structure.