Laboratory calibration of a low-cost optical particle counter

Optical particle counters (OPCs) measure the concentration and size distribution of particulate matter on a real-time basis. They are commonly used for monitoring outdoor and indoor ambient air, identifying pollution sources and predicting urban air quality. They rely on a light scattering method and if the particle density is known, the mass concentration of the pollutant can be determined. Progress in modern sensor techniques have seen the commercialisation of smaller, cheaper and portable devices that might improve our capacity to characterise aerosol concentrations with high spatial and temporal resolution (Holstius et al., 2014). The aim of this study was the characterisation of a low cost OPC (Compact OPC N1, Alphasense; hereafter COPC), chosen for its size and manageability.