How many total SFRM thickness measurements are required on a joist?

The requirement for a total of 14 SFRM (Sprayed Fire-Resistive Material) thickness measurements on a joist is based on industry standards for ensuring adequate fireproofing coverage and performance. This number is established to adequately assess and document the thickness of the fireproofing material applied to structural components, such as joists, to ensure they achieve the desired fire-resistance rating.

The measurement process involves taking multiple readings to account for potential variations in application due to factors such as surface irregularities, unevenness in substrate, or variations in spray application technique. By specifying 14 measurements, the standards ensure that there's a thorough assessment of the SFRM application, helping to identify any deficiencies that could compromise the structural integrity or fire protection performance of the joists in a fire event.

In the context of construction and fire safety, thorough measurement and adherence to recommended practices are vital for compliance with codes and standards, ultimately ensuring occupant safety and structural performance during a fire incident.