| Name | Type | Country | Components |
|---|---|---|---|
| Aarhus University Research on Aerosols smog chamber facility (AURA) | Atmospheric simulation chamber | Denmark | 1 |
| ACTRIS-Poland Mobile LAB | Mobile platform | Poland | 1 |
| Aerosol, cluster and trace gas laboratory (Helsinki) | Laboratory platform | Finland | 2 |
| Aerosol from Ground to Cloud Mobile Experiment (ACME) | Mobile platform | Germany | 2 |
| Aerosol Interaction and Dynamics in the Atmosphere (AIDA) | Atmospheric simulation chamber | Germany | 2 |
| AGORA | Observational platform | Spain | 3 |
| ATMOSLAB | Mobile platform | Romania | 3 |
| Atmospheric Chemistry Department Chamber (ACD-C) | Atmospheric simulation chamber | Germany | 2 |
| Atmospheric Observatory of LiLle (ATOLL) | Observational platform | France | 2 |
| Atmospheric Rome joinT supersitE | Observational platform | Italy | 1 |
