Abstract

Continuous measurements of PM10, PM2.5, and PM1 concentrations were carried out by collocating a GRIMM Aerosol Laser Spectrometer model 11-C as a reference instrument and three Plantower PMS7003 low-cost sensor (LCS) from June 11, 2019, to April 23, 2020, in a residential/ commercial area of the city of Santiago de Chile. Completeness, precision, linearity, bias, and error metrics were analyzed to evaluate the performance of PMS7003. Linear regression and quadratic polynomial models were proposed to correct the concentrations provided by LCS based on the environmental variables studied. The performance of the LCS was outstanding for the PM1 fraction, obtaining R2 = 0.98, slope = 1.1. PM2.5 and PM10 concentrations were underestimated in drier and warmer summer conditions and slightly overestimated in colder and wetter winter conditions. In the case of PM2.5, three correction models were proposed, two of which considered four possible conditions based on the relative humidity and temperature to identify their influence on the LCS performance, achieving R2 values of 0.869 and 0.875, respectively. The LCS showed low linearity and bias value for PM10; the correction model for this PM fraction with the highest value in the metrics obtained an R2 = 0.630, therefore its use is recommended only for educational purposes.