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An example of the information provided by air monitoring stations in Beijing, China. Besides the usual temperature, dew, pressure, humidity, and wind values in hourly readings, the information on following pollutants can be seen: particular matter 2.5 (PM2.5), PM10, O3, NO2, SO2, and CO. Here, the unhealthy status is based on current highest PM2.5 values. The figure is reproduced with permission [11].
