Method for detecting the concentration of organic particles in the air and apparatus therefor

A method for detecting a concentration of organic particles (14), in particular viruses, with a determined target diameter in air (10) which comprises organic and/or inorganic aerosol particles,

• wherein aerosol particles contained in the air (10) are bound in a fluid (40), so that said aerosol particles are contained as particles in the fluid (40),
• wherein the fluid (40) with the particles contained therein is exposed in a measurement chamber (30) to a second light (B) fragmenting the organic particles and/or to an ultrasound (C) fragmenting the organic particles, so that the organic particles are fragmented in the fluid (40),
• wherein before the fragmentation of the organic particles, a first light scattering of a first light (A) and after the fragmenting of the organic particles, a second light scattering of the first light (A) on the fluid (40) are determined, and, from a difference between the first light scattering and the second light scatterings, the concentration of the organic particles (14) in the fluid (40) and thus in the air is determined.