https://99designs.com/logo-design/contests/clean-air-solutions-symbolkraft-f%C3%BCr-feinstaubsauger-gesucht-879035/entries/4
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Kreiert mit 99designs von Vista
funny and serious logo -> "Switch off a Fine Dust Cloud" or "cleaning air" with fine vacuum cleaner at (Office, Home, Outside) Fine vacuum cleaner = fine dust & vacuum cleaner = here air filtration systems.