A smoke detector is an electronic fire-protection device that automatically senses the presence of smoke, as a key indication of fire, and sounds a warning to the building occupants.
In this project, we have used MQ-2 gas sensor. It is a metal oxide semiconductor, which is a robust Gas sensor suitable for sensing LPG, Smoke, Alcohol, Propane, Hydrogen, Methane and Carbon Monoxide concentrations in the air. We have also included a buzzer and an LED connected to the microcontroller.
The detector will detect the smoke and notify the user through the buzzer and red LED if the smoke density is above the safety limit.