Scholarly record
CORRELATION BETWEEN MEASUREMENTS MADE BY THE GRAVIMETRIC METHOD AND THE OPTICAL METHOD FOR THE DETERMINATION OF PM10 DUST IN AMBIENT AIR
Abstract
Dust sampling equipment exhibits significant variations over time depending on the operating principle, being influenced by interaction of environmental factors, such as air flow velocity, relative humidity, ambient temperature and barometric pressure. The objective of this study is to perform a comprehensive comparative evaluation between the gravimetric reference method and the optical method for determining PM10 particles in ambient air. In order to allow the evaluation of each observation in relation to method variability of the measured method, z scores were calculated for each method separately. The analysis shows that the z-score obtained from the optical method highlights the tendency of the optical method to amplify extreme values. Such results are consistent with the hypothesis that optical instruments are more sensitive to external factors (e.g. air humidity), especially at higher concentrations. The comparison shows that the average values of optical measurements are 1.2 micrograms per cubic meter higher than gravimetric concentrations.
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References5
Chow, J.C., Watson, J.G., Lowenthal, D.H., et al. (2015). PM2.5 chemical composition and source apportionment. Atmospheric Environment.
Titos, G., et al. (2016). Evaluation of optical particle counters for PM monitoring. Atmospheric Measurement Techniques.
Crilley, L.R., et al. (2018). Evaluation of low-cost optical particle counters. Atmospheric Measurement Techniques.
Jayaratne, R., et al. (2018). Influence of humidity on optical particle sensors. Atmospheric Environment.
Sousan, S., Koehler, K., Hallett, L., Peters, T.M. (2016). Evaluation of consumer aerosol monitors. Journal of Aerosol Science.