Arduino-Based smoke detector and Fire Detection System Using Gas Sensor

Fire smoke detector project for kids

Overview

This project deals with a fire or smoke detector using a Gas Sensor, which senses the threshold value for the smoke and gives input to the buzzer and LEDs accordingly.

In this smoke detector, when the gas sensor detects a value greater than 300, the buzzer and LED – Red get activated, and if the value is less than 300, then the LED – Green will be activated.

Hardware required 

1. Arduino Uno R3
2. LED
3. Resistor
4. Jumper Wires
5. Gas Sensor
6. Buzzer

Schematic Diagram

Fig 1.  Circuit Diagram

Arduino Code :

int redLed = 12;
int greenLed = 11;
int buzzer = 10;
int smokeA0 = A5;
int sensorThres = 300;

void setup() {
  pinMode(redLed, OUTPUT);
  pinMode(greenLed, OUTPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(smokeA0, INPUT);
  Serial.begin(9600);
}

void loop() {
  int analogSensor = analogRead(smokeA0);

  Serial.print("Pin A0: ");
  Serial.println(analogSensor);
  if (analogSensor > sensorThres)
  {
    digitalWrite(redLed, HIGH);
    digitalWrite(greenLed, LOW);
    tone(buzzer, 1000, 200);
  }
  else
  {
    digitalWrite(redLed, LOW);
    digitalWrite(greenLed, HIGH);
    noTone(buzzer);
  }
  delay(100);
}

Precautions

1. Connections should be done properly.
2. Arduino is case Sensitive, so code accordingly.
3. Give different and appropriate colours to the wires.
4. Use resistors for sensors and LEDs.

Conclusion:

This project demonstrates how simple yet effective an Arduino-based smoke detector can be when combined with a gas sensor, buzzer, and LEDs. By setting a threshold, the system provides instant alerts for smoke or fire hazards, making it a practical safety solution. Such projects not only enhance technical skills but also spark creativity in electronics and coding.

Platforms like coding schools play a vital role in guiding learners to build real-world applications with Arduino and sensors. Exploring hands-on experiments encourages innovation while strengthening problem-solving skills for budding engineers and hobbyists alike.