Air Quality

The PMSA003I is a high-precision laser-based particulate matter (PM) sensor designed for real-time air quality monitoring in the 3D-PAWS system. This sensor continuously measures and reports the concentration and number of airborne particles of various sizes, providing detailed insight into local air pollution.

How It Works Internally

• Laser Scattering Principle: The PMSA003I uses a laser and a fan to draw air into its detection chamber. As particles pass through the laser beam, scattered light is detected and analyzed to determine particle size and count.

• Particle Output: The sensor outputs both the number and mass concentration of particles in several size bins (e.g., PM1.0, PM2.5, PM10).

  • Number concentration is reported as particles per 0.1 L of air.

  • Mass concentration is reported in micrograms per cubic meter (μg/m³).

• Adaptive Sampling Modes:

  • Stable Mode: When air quality is steady, the sensor samples at a real interval of 2.3 seconds.

  • Fast Mode: If particle concentrations change rapidly, the sensor automatically switches to fast mode, sampling every 200–800 ms. The higher the concentration, the faster the sampling.

• 3D-PAWS Integration: The 3D-PAWS system samples the PMSA003I every second, recording the highest 1-second value observed during each measurement interval for robust air quality tracking.

Power Considerations & Recommendation

Note: The PMSA003I is a power-hungry sensor because it runs a fan continuously to ensure accurate, real-time sampling. This significantly increases the station’s energy requirements.

For reliable operation, we strongly recommend using a Voltaic V75 battery and a 10 W, 6 V solar panel for air quality stations equipped with this sensor.

Instruction Slides