Ambient air quality monitoring housing comprising an external wall configured for enclosing a sensing unit having a sensing region , wherein the housing comprises - an airflow inlet configured for receiving incoming ambient air, - a U-shaped path comprising: ∘ a straight first part of the U-shaped path , the straight first part being in fluid communication with the airflow inlet and configured for: ▪ receiving the incoming ambient air, and ▪ providing an airflow direction, ∘ a bended second part defining the bended part of the U-shaped path , being in fluid communication with the straight first part and configured for turning the airflow direction, and ∘ a straight third part of the U-shaped path , the straight third part being in fluid communication with the bended second part , characterised in that the relative position of the straight third part is configured with respect to the sensing unit such that the airflow flowing through the straight third part is directed parallel to the sensing region of the sensing unit so that the sensing region is able to detect and measure particles and gases entrained in the ambient air, - and in that the airflow inlet is located transversally to the longitudinal direction of the straight first part of the U-shaped path . - an airflow inlet configured for receiving incoming ambient air, - a U-shaped path comprising: ∘ a straight first part of the U-shaped path , the straight first part being in fluid communication with the airflow inlet and configured for: ▪ receiving the incoming ambient air, and ▪ providing an airflow direction, ∘ a bended second part defining the bended part of the U-shaped path , being in fluid communication with the straight first part and configured for turning the airflow direction, and ∘ a straight third part of the U-shaped path , the straight third part being in fluid communication with the bended second part , characterised in that the relative position of the straight third part is configured with respect to the sensing unit such that the airflow flowing through the straight third part is directed parallel to the sensing region of the sensing unit so that the sensing region is able to detect and measure particles and gases entrained in the ambient air, ∘ a straight first part of the U-shaped path , the straight first part being in fluid communication with the airflow inlet and configured for: ▪ receiving the incoming ambient air, and ▪ providing an airflow direction, ▪ receiving the incoming ambient air, and ▪ providing an airflow direction, ∘ a bended second part defining the bended part of the U-shaped path , being in fluid communication with the straight first part and configured for turning the airflow direction, and ∘ a straight third part of the U-shaped path , the straight third part being in fluid communication with the bended second part , characterised in that the relative position of the straight third part is configured with respect to the sensing unit such that the airflow flowing through the straight third part is directed parallel to the sensing region of the sensing unit so that the sensing region is able to detect and measure particles and gases entrained in the ambient air, - and in that the airflow inlet is located transversally to the longitudinal direction of the straight first part of the U-shaped path . <EOS>