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        Swiss Environmental Protection Agency (BAFU), Bern | 
        
       
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        The Swiss Federal Research Institute EMPA in Dübendorf | 
        
       
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        Department of Commerce of the Duchy of Liechtenstein | 
        
       
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        States of Austria: Tyrol, Vorarlberg, Salzburg, Kärnten, Oberösterreich, Niederösterreich | 
        
       
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        OSTLUFT (ambient air survey institution in eastern Switzerland)
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        | The following cantonal EPAs: | 
        
       
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        Aargau, Zürich, Solothurn, Freiburg, Grisons, Lucerne, Nidwalden, Ticino, Uri, Zug, St. Gall, Bern, Glarus, Basel, Neuchâtel, Valais.
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        | Cities and municipalities: | 
        
       
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        Zürich, Lucerne, Baden, Davos, Bonstetten, Wettswil as well as several others. | 
        
       
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        In Luft, monitoring network of Central Switzerland | 
        
       
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        Swiss Federal Railways | 
        
       
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        Brenner Railway Company (BEG), Austria | 
        
       
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        Various companies with industrial plants | 
        
       
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        Asfinag (Austrian Highways Society) | 
        
       
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        Various service companies | 
        
       
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        Trade and industry associations | 
        
       
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