NO2 emissions are known to be primarily generated by industrial facilities or vehicle exhausts. Recently, a research team from POSTECH analyzed satellite remote sensing data from ESA and released results showing that food processing facilities and high-rise apartments that are 10 stories or higher are significant sources of NO2 emissions. The team estimated average NO2 concentrations at the spatial resolution of 500 m in California between 2018 and 2019 and assessed whether NO2 concentrations measured at ground monitors were representative of population exposures to NO2 in each county. They also evaluated which property types showed the highest NO2 emissions and therefore exposures. Their assessment revealed that the highest NO2 exposures were attributed to food processing facilities and high-rise apartments that are 10 stories or higher. The same results were obtained when traffic was taken into consideration.