What is the minimum allowable average TFIFRM thickness for a beam requiring 48 mils of thickness?

The minimum allowable average thickness for fireproofing a beam is established to ensure that the protective layer effectively provides the necessary fire resistance. A requirement of 48 mils indicates a specific standard that must be met to protect the structural integrity of the beam during a fire event.

When the standard specifies 48 mils of thickness, the expectation is that the fireproofing system will deliver the specified thickness uniformly across the beam’s surface. Having a minimum average thickness of 100% means that the average measurement must indeed meet or exceed the specified thickness of 48 mils, without allowances for any percentage less than that.

This ensures that in situations of exposure to fire, the fireproofing will perform as intended—maintaining the structural stability required to withstand heat and potential collapse. Any deviation below this standard could compromise the effectiveness of the fireproofing, which is critical for the safety of the structure and occupants.

Other percentages below 100% would not meet the regulatory or safety standards for adequate fireproofing, which is why 100% is the correct answer for this specific requirement.