MQ-135 : AIR QUALITY DETECTION SENSOR

                                                    An MQ-135 sensor is used for detecting poisonous gases that impact air quality. It is suitable for detecting ammonia (NH3), nitrogen oxides benzene, smoke, CO2 and other harmful or poisonous gases that impact air quality. The MQ-135 sensor unit has a sensor layer made of tin dioxide (SnO2), an inorganic compound which has lower conductivity in clean air than when polluting gases are present. We can interface MQ 135 sensor with Arduino to detect the air quality.

Application:

• The MQ-135 sensor can detect or measure Air Quality.
• To sense the quality of air.
• To check the quality of air by knowing the composition of oxygen in air.

Sample Project With Arduino:

                                 In this we going to detect the level of air quality using the MQ-135 sensor.

Materials required:

• MQ-4 gas sensor
• Arduino UNO
• Jumper wires

Circuit:

Code:

int sensorValue;

int digitalValue;

void setup()

{ Serial.begin(9600);  // sets the serial port to 9600

pinMode( 0, INPUT);

}

void loop(){

  sensorValue = analogRead(0);  // read analog input pin 0

  digitalValue = digitalRead(0);

  Serial.println(sensorValue, DEC);  // prints the value read

 Serial.println(digitalValue, DEC);

 delay(2000);  // wait 100ms for next reading

}