A room has the dimensions of

10m

long,

8m

wide and

3m

high and a window of

2m

long and

1.5m

high. A

10kg

wood sofa is ignited. The room temperature is

20\\\\deg C

, and heat of combustion of wood is

18.6M(J)/(k)g

\ (a) If the initial fire heat release rate is

500kW

, can it always trigger the heat detector (RTI =

50m^((1)/(2))s^((1)/(2))

) with a threshold temperature of

65\\\\deg C

?\ (6 marks)\ (b) What is the shortest possible time to trigger the heat detector?\ (9 marks)\ (c) If there are 20 sofas in the room, and flashover occurs in

3min

, what is the total burning duration?\ (10 marks)

A room has the dimensions of 10m long, 8m wide and 3m high and a window of 2m long and 1.5m high. A 10kg wood sofa is ignited. The room temperature is 20C, and heat of combustion of wood is 18.6MJ/kg (a) If the initial fire heat release rate is 500kW, can it always trigger the heat detector (RTI= 50m1/2s1/2 ) with a threshold temperature of 65C ? (6 marks) (b) What is the shortest possible time to trigger the heat detector? (9 marks) (c) If there are 20 sofas in the room, and flashover occurs in 3min, what is the total burning duration? (10 marks)