Fire Resistance Rating

• A. The smoke development rating of a partition.
• B. The fire duration rating used for insulation materials only.
• C. The time, in minutes or hours, that materials or assemblies have withstood a fire exposure as determined by the tests, or methods based on tests, prescribed by this Code.
• D. The energy absorption capacity of a barrier.

Answer: (C)

Fire resistance rating is the time, in minutes or hours, that a material or assembly can withstand a standardized fire exposure while still performing its intended function. This rating comes from fire tests (such as ASTM E119 or UL 263) and is used to determine how long a barrier can delay fire spread, maintain structural stability, and limit heat transfer during the test. It applies to walls, floors, doors, and other assemblies, not just insulation, and it’s separate from how much smoke is produced or how much energy the material can absorb.