Applicability of factory calibrated optical particle counters for high-density air quality monitoring networks in Ghana

In this study, we demonstrate the feasibility of using miniaturised optical particle counters (OPCs) for understanding AQ in Sub-Saharan Africa. Specifically, the potential use of OPCs for high-density ground-based air pollution networks and the use of derived data for quantification of atmospheric emissions were investigated. Correlation and trend analysis for particulate matters (PM), including PM(10), PM(2.5) and PM(1) were undertaken on hourly basis alongside modelled meteorological parameters. Hourly averaged PM values were 500 μg/m(3), 90 μg/m(3) and 60 μg/m(3) for PM(10), PM(2.5) and PM(1), respectively and Pearson's correlation coefficient ranged between 0.97 and 0.98. These levels are in the agreement with range of PM emission reported for these types of environmental settings. PM was locally associated with low wind speeds (<= 2 ms(−1)) and was closely linked to anthropogenic activities. This study provides a benchmark for future AQ and demonstrates the feasibility of the current generation of OPCs for AQ monitoring in environments typical of large parts of West and Sub Saharan Africa.