MQ-135 Air Quality Sensor Module for Arduino Raspberry Pi IoT Projects Detects Benzene Alcohol Smoke DIY Electronics Kit SKU-9528
Disclosure: Best Components earns from qualifying purchases as an Amazon Associate. Availability may change.
“A competent budget sensor for relative air quality tracking in DIY projects, but unsuitable for applications demanding absolute accuracy or regulatory compliance.”
Our Review
The MQ-135 delivers solid baseline air quality monitoring for hobbyist IoT projects, though it requires realistic expectations about accuracy. The sensor detects ammonia, benzene, and smoke effectively enough for relative trending rather than calibrated measurements. Integration with Arduino and Raspberry Pi is straightforward via analog output, and the included module PCB simplifies breadboard prototyping. However, the sensor exhibits significant drift without regular calibration, and the datasheet claims are optimistic—don't expect laboratory-grade ppm readings. Response time runs 10-30 seconds, which limits real-time applications. For environmental logging or home automation alerts, it performs adequately after accounting for its limitations.
What We Like
- Simple analog interface compatible with both Arduino ADC and Raspberry Pi with MCP3008 converter
- Dual output pins (analog + digital threshold) enable flexible trigger-based applications
- Compact module form factor with onboard resistor network reduces external components
Watch Out For
- Requires 48-hour warm-up period and frequent recalibration to maintain accuracy—drift is noticeable within weeks
- Cross-sensitivity issues make distinguishing between specific gases unreliable without additional sensors
The Verdict
“A competent budget sensor for relative air quality tracking in DIY projects, but unsuitable for applications demanding absolute accuracy or regulatory compliance.”
Related Sensors & Modules Components
