MQ135 Air Quality Gas Sensor

MINIMUM TECH FEATURES

• Power Supply: 2.5V ~ 5.0V
• Power Consumption: < 800 mW
• Operating Temperature: -10°C to +50°C
• Relative Humidity: < 95% RH
• Response Time: < 10 seconds
• Dimensions: 40 × 21 × 16 mm
• Weight: 7 g

DESCRIPTION

• The MQ135 is a versatile air quality sensor designed to detect multiple harmful gases, making it suitable for indoor and outdoor air monitoring applications.
• It can sense ammonia (NH₃), alcohol, benzene, smoke, CO₂, and various other volatile organic compounds (VOCs).
• The sensor is highly sensitive to ammonia, sulphide gases, and smoke, providing reliable readings for environmental changes.
• It outputs an analog signal proportional to the gas concentration—higher concentrations produce higher output voltage.
• A 24-hour burn-in period is required for optimal accuracy, especially during first-time use.
• The sensing element includes a heating component and a SnO₂ (tin dioxide) layer whose conductivity changes in the presence of detectable gases.
• Built with a robust housing, the sensor maintains stable performance and typically lasts 2–3 years under normal operating conditions.
• Its compact design makes it easy to integrate with Arduino, Raspberry Pi, ESP32, and other microcontroller platforms.

TECHNICAL SPECIFICATIONS

APPLICATIONS

• Air Quality Monitoring Systems
• Indoor Air Quality (IAQ) Monitors
• Smart Home Devices
• Environmental Monitoring
• Industrial Safety Systems
• Toxic Gas Detectors
• Leak Detection Systems
• Emission Control Systems
• Smoke and Fire Detection Systems
• Smoke Detectors
• Fire Alarms
• Automotive Air Quality Monitoring
• HVAC & Ventilation Systems
• Environmental Research
• Agriculture and Animal Husbandry