Nitrogen dioxide is a nasty smelling important air pollutant in urban areas and cities. It contributes to the formation of smog and can severely impact human health if exceeding a certain concentration. Major sources of nitrogen dioxide are the burning of fossil fuels, motor vehicle exhaust, petrol and metal refining, electricity generation and other manufacturing industries.
Sulfur dioxide is noticeable component in the atmosphere as well as a major air pollutant. Exceeding a certain concentration, the gas has a significant impact upon human health, the habitat suitability for plants as well as for animal life. Emissions of SO2 are a precursor to acid rain and atmospheric particulates.
The sampler collects NO2 and SO2 by molecular diffusion along an inert tube to an absorbent, in this case mixture of potassium carbonate, glycerol and triethanolamine.
The passive sampler is composed of a polypropylene housing with an opening of 20 mm diameter. To reduce wind disturbance a glass fibre membrane is attached, supported by a wire net. The sampler is placed in a specially designed shelter to protect it during its exposure.