A single layer or multilayer assembly is tested by face ignition. Limited spread of flame of the specimen is determined when a calibrated flame is applied to the surface of the vertically oriented specimen for 10 seconds.

"After flame" (persistence of flaming of material after the ignition source is removed), "after flame" time (the time duration for which the material continues to flame after the removal of flame) and "after glow" (persistence of glowing combustion) is recorded.

Molten debris and formation of hole, if any, are also reported for classification of the material.