cf95dee8_cascade_impactor___LabAutomate__NGI
[0] Flight path of the aerosol particles [A3G] Same as in the ACI [NGI] 
At least twice as long as in the ACI. To prevent aerosol droplet evaporation, many people have started to freeze their NGIs prior to use, thus severely restricting throughput and increasing cost. Without the freezing step, the data is biased more towards the fine particle fraction.
andersen-cascade-impactor - LabAutomate
NGI