What This DIY Arduino Air Quality Monitor Does
An Arduino air quality monitor is a DIY air sensing system that uses an Arduino board and external sensors to measure fine particulate matter like PM2.5, then reports and logs those readings in real time so you can track indoor or outdoor pollution and respond with ventilation, filtration, or behavior changes. In this project, you will build a PM2.5 sensor Arduino setup around the Arduino GIGA R1, paired with the DFRobot PM2.5 Sensor (SEN0460) using its Gravity I2C interface. The GIGA R1’s dual-core STM32H747XI microcontroller, 2MB flash, 1MB RAM, and extra SDRAM provide enough power for real-time measurements, data logging, and optional wireless features. The result is a DIY air quality system that rivals many commercial monitors while remaining accessible to hobbyists who want better insight into the air in their homes, offices, or research sites.
Hardware Setup: Arduino GIGA R1 and DFRobot PM2.5 Sensor
Start your Arduino GIGA R1 project by preparing the development board in the Arduino IDE. Install the latest IDE, add the “Arduino Mbed OS GIGA Board Package” in Boards Manager, then select Arduino GIGA R1 WiFi and the correct USB-C port. The board runs at 3.3 V logic, so avoid sending 5 V to any GPIO pins. According to DFRobot, the PM2.5 Sensor SEN0460 works from 3.3 V to 5 V and accepts 3.3 V I2C signals even when powered at 5 V. Wire VCC to 5 V, GND to GND, SDA to pin 20, and SCL to pin 21, using the default I2C1 (Wire) bus. The sensor’s default I2C address is 0x19, which you can confirm using an I2C scanner sketch before moving on to coding and calibration.
Programming the PM2.5 Sensor on Arduino
With the wiring complete, install the “DFRobot AirQualitySensor” library via Sketch → Include Library → Manage Libraries. This library hides the low-level protocol and exposes clear functions to query PM1.0, PM2.5, and PM10 values. Create a DFRobot_AirQualitySensor object on Wire with address 0x19, then call begin() in setup() inside a retry loop so the sketch waits until the sensor responds. In loop(), use gainParticleConcentration_ugm3() with PARTICLE_PM1_0_STANDARD, PARTICLE_PM2_5_STANDARD, and PARTICLE_PM10_STANDARD to read concentrations in µg/m³ every second and print them to the Serial Monitor at 115200 baud. You can also read atmospheric values, though the standard outputs are recommended for general use. A simple if/else block can categorize PM2.5 readings as Good, Moderate, or Unhealthy to give non-technical users an immediate sense of current air quality.
Calibration, Data Logging, and Trend Analysis
To make your Arduino air quality monitor more reliable, focus on repeatable calibration and data logging. Begin by running the sensor in a stable, clean environment to understand its baseline PM1.0, PM2.5, and PM10 values, then compare readings with a reference monitor if available. The GIGA R1’s processing power and multiple interfaces allow you to add SD card storage for CSV logging, capturing timestamps alongside particle concentrations for later analysis in spreadsheets or plotting tools. Over days or weeks, this data reveals trends related to cooking, cleaning, traffic patterns, or seasonal changes. Because the DFRobot PM2.5 sensor uses laser-scattering technology to measure particles from 0.3 µm to 10 µm, it can highlight fine particulate spikes that matter most for health-focused trend tracking in homes, offices, or outdoor research deployments.
Expanding Your DIY Air Quality System
Once the core PM2.5 sensor Arduino build is running, you can extend the DIY air quality system in several directions. The Arduino GIGA R1 provides 76 GPIO pins, three I2C ports, four UARTs, and two SPI ports, so there is room to add temperature, humidity, or gas sensors alongside the DFRobot module. You can connect an LCD or OLED to display live data, or use Wi-Fi and Bluetooth connectivity on the GIGA R1 to push readings to an IoT dashboard for remote access and alerts. With extra storage, you can keep long-term logs for environmental research projects or building monitoring. This flexible, budget-friendly platform lets you tune sampling rates, AQI thresholds, and output formats so your air quality monitor fits your space, from a single room to a distributed sensor network.
