The HEPA-filter ensures cleanness of the carrier gas (nitrogen). In the atomizer a NaCl-solution is sprayed. Downstream the atomizer a diffusion dryer removes the water from the droplets to produce small crystals. The salt crystals concentration for the heterogeneous condensation is about 1E6 … 1E7 per cm³. By means of the screen-bypass downstream to the diffusion dryer the nuclei concentration can be adjusted.The size of the aerosol particles to be produced is mainly determined by the quantity of available vapour per nucleus. The vapour concentration can be adjusted by two parameters: Saturation of the nuclei aerosol at definite temperature; Dilution of the saturated nuclei aerosol with not saturated nuclei aerosol by means of a saturator bypass.

The saturation of the nuclei aerosol takes place in the saturator. The aerosol bubbles through the aerosol material which is held at constant temperature. Depending on the temperature and the material specific vapour pressure a definite saturation concentration of vapour is achieved in the bubbles. The bypass permits the more rapid adjustment of particle size by dilution, rather than by saturator heating or cooling. In the condensation chimney the superheated vapour-nuclei mixture is cooled down causing the vapour to condense onto the nuclei. For particularly high demands on the monodispersity only the core flow in the condensation chimney is exhausted.

The SLG 270 is also equipped with a screen unit for the defined salt core reduction (screen), which allows the generation of larger particles.