Evaluating Low-Cost Commercially Available Sensors for Air Quality Monitoring and Application of Sensor Calibration Methods for Improving Accuracy

In this paper, we present the results of the evaluation of three low-cost laser sensors and comparison with the standard device Metone Aerocet 531s which is capable of counting dust particles as small as 0.3 μm. The sensors used in this study are PMS5003 (Plantower), SPS30 (Sesirion), SM-UART-04L (Amphenol). During the measurement, the overall trend of the outputs from the sensors was similar to that of the Aerocet 531s. The PMS5003 sensor has a relatively small standard error in the all particle measurement ranges (3 in the low particle concentration range). All sensors have a high linearity compared to data from standard equipment, PMS5003: PM1.0 R2 = 0.89; PM2.5 R2 = 0.95; PM10 R2 = 0.87; SPS30 PM2.5 R2 = 0.95 and PM10 R2 = 0.99; SM-UART-04L PM1.0 R2 = 0.98. Three main sensor calibration methods (single-point calibration, two-point calibration and multi-point curve correction) with implementation steps for each method as well as their practical applications in calibrating low-cost air quality sensors according to standard measuring equipment are also detailed illustrated.