6-in-1 Personal Air Quality Monitor — PM2.5, PM10, CO₂, VOC, Temperature & Humidity

Particulate matter smaller than 2.5 μm penetrates alveolar tissue — this laser-scattering sensor counts every particle in real time, in the air you're breathing right now.

The PM2.5/PM10 sensor uses laser light scattering (Mie scattering theory): a 650 nm diode laser illuminates a sample chamber, and a photodetector counts forward-scattered pulses. Pulse count per unit volume is converted to mass concentration (μg/m³) using empirical aerosol density models. The electrochemical CO₂ sensor (NDIR — non-dispersive infrared) measures 4.26 μm CO₂ absorption. The MOX (metal-oxide) VOC sensor measures resistance changes caused by reducing gases adsorbing onto a heated tin-oxide sensing element — the same physics as a Taguchi gas sensor from 1971.

• PM2.5 (0–999 μg/m³, ±10%) + PM10 laser particle counting
• CO₂ NDIR: 400–5000 ppm (±50 ppm); VOC MOX sensor: 0–9.99 ppm equivalent
• Temperature: ±0.5 °C; Relative Humidity: ±3% RH
• 2.8-inch colour TFT with AQI gauge, historical graph; USB-C rechargeable

Every purchase directly funds independent physics research at the Golden Physics Project.