Fire Resistance Level
Fire Resistance Level (FRL) as defined in the Building Code of Australia (BCA) is the grading period in minutes for three criteria: structural adequacy, integrity and insulation.
- Structural adequacy means the ability of a structure to maintain its stability and loadbearing capacity;
- Integrity means the ability of a structure to resist the passage of flames and hot gases and
- Insulation means the ability of a structure to maintain a temperature below specified limits on the surface not exposed to fire.
Hence, a FRL requirement for a wall of 90/60/30 means that the wall must maintain structural adequacy for 90 minutes, integrity for 60 minutes and insulation for 30 minutes, as tested to AS 1530.4-1990: “Methods for fire tests on building materials, components and structures – Fire-resistance tests of elements of building construction”.
References: Building Code of Australia