Automated fire fighting system with smoke and temperature detection

In the present work, we fabricated an automated fire fighting system with locally available components. The system can response in presence of smoke and high temperature. If any or both of smoke and temperature above a certain limit are sensed, the alarm goes on warning and the valve of a water spraying nozzle opens to extinguish the fire. The presence of smoke and temperature is sensed by the change of resistance of a LDR or a NTC accordingly. A latch circuit is incorporated to make the alarm continuous. The system is effective and as well as cheap.