UFIPOLNET - Ultrafine Particles
![Comparison pinhead to rock: Ultrafine particles to diameter of a hair](/umwelt/img/luft/UFIPOLNET_groessenvergleich_361_rdax_413x310.jpg)
Ultra fine particles are 1000-times smaller than the diameter of a human hair. They are smaller than 100 nanometer. Unthinkable small: If a 2 meter rock would equal to the diameter of a hair the pinhead would equal to an ultrafine particle.
Particles in environmental aerosols are in the size range from one nanometer to 100 micrometer (µm = millionth part of one meter). They can be put into specific size ranges dependent on their origin. Particles smaller than 10 µm are important for the human health.
![Different sizes of particles in aerosols of the ambient air](/umwelt/img/luft/UFIPOLNET_pm_bereich_327_rdax_413x205.jpg)
Particles in environmental aerosols are in the size range from one nanometer to 100 micrometer (µm = millionth part of one meter). They can be put into specific size ranges dependent on their origin. Particles smaller than 10 µm are important for the human health. Source: modified from O. Meckes/EOS/Agentur Focus
![Figure: Diesel soot is one of the harmful substances to health, which are in ultrafine particles. (Photo: Ulrich Heinzmann)](/umwelt/img/luft/413_dieselruss.jpg)
![Composition of fine particles in Dresden, Schlesischer Platz near road traffic](/umwelt/img/luft/413_feinstaubzusammensetzun.gif)