An Overview of Fire Resistance Rating in Construction
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Passive fire protection systems and materials must be able to withstand standard fire resistance tests in order to be considered fire resistant. Fire resistance Rating (FRR) refers to a construction material or assembly's ability to withstand a standard fire exposure for a specified period of time, in minutes or hours. Fire Resistant Rating Features The fire resistance of a material or assembly is measured by its FRR. To determine it, a standardized fire test and calculation are used. Additionally, a fire rating level (FRL) is determined by the test result obtained after testing fire resistance.