MQ-135 Air Quality Sensor
The MQ-135 Air Quality Sensor is a versatile gas sensor designed to monitor indoor air quality by detecting harmful gases such as ammonia (NH₃), benzene, smoke, alcohol vapors, nitrogen oxides (NOx), sulfides, and other volatile organic compounds (VOCs). It is widely used in Arduino, ESP32, Raspberry Pi, and IoT-based environmental monitoring projects.
Features
- Detects multiple harmful gases and pollutants
- High sensitivity with fast response and recovery time
- Analog (A0) and Digital (D0) output options
- Adjustable sensitivity via onboard potentiometer
- Long lifespan and stable performance
- Compatible with Arduino, ESP8266, ESP32, Raspberry Pi, and other microcontrollers
Technical Specifications
| Parameter |
Value |
| Operating Voltage |
5V DC |
| Output Type |
Analog & Digital |
| Detection Gases |
NH₃, NOx, Benzene, Alcohol, Smoke, CO₂ (indirectly), VOCs |
| Detection Range |
10–1000 ppm (gas dependent) |
| Heater Consumption |
≤ 800mW |
| Operating Temperature |
-10°C to 45°C |
| Humidity Range |
<95% RH |
| Preheat Time |
24 hours recommended for accurate calibration |
Pin Configuration
-
VCC – 5V Power Supply
-
GND – Ground
-
A0 – Analog Output
-
D0 – Digital Output (threshold adjustable)
Applications
- Indoor Air Quality Monitoring
- Smart Home Automation
- Air Pollution Detection Systems
- Industrial Safety Monitoring
- Gas Leakage Detection
- Environmental Monitoring Projects
- IoT-Based Air Quality Stations
Package Includes
- 1 × MQ-135 Air Quality Sensor Module