A SHORT NOTE ON USING A TIME CONSTANT IN SPECIFYING SMOKE FILLING TIME IN AN ATRIUM UNDER AN UNSTEADY FIRE

A time constant derived from at-squared fire with the geometry of an a trium is proposed to specify the smoke filling time. The smoke filling processes in 27 atria with volume varying from 2,500 to 35,000 m(3) w ere simulated by the fire zone model CFAST version 2.0. The atria are located adjacent to a ''fire'' shop at a lower level. Correlation rela tionships between the smoke filling time and the time constant are der ived. Further, performance of smoke control systems in the atria are e valuated.