sources on a local scale. It is a Gaussian plume model for point, area, line and vehicular traffic sources. It includes plume penetration of inversions aloft, building effects, NOx chemistry and it can handle street canyons. It does not include wet or dry deposition, complex atmospheric chemistry, or the effects of complex terrain. DISPLAY-2 (Greece) – A vapour cloud dispersion model for neutral or denser-than-air pollution plumes over irregular, obstructed terrain on a local scale. It accommodates jet releases as well as two-phase (i.e., liquid-vapor mixtures) releases. This model was also developed at the National Centre of Scientific Research "DEMOKRITOS" of Greece. EK100W (Poland) – A Gaussian plume model used for air quality impact assessments of pollutants from industrial point sources as well as for urban air quality studies on a local scale. It includes wet and dry deposition. The effects of complex terrain are not included. FARM (Italy) – The Flexible Air quality Regional Model (FARM) is a multi-grid Eulerian model for dispersion, transformation and deposition of airborne pollutants in gas and aerosol phases, including photo-oxidants, aerosols, heavy metals and other toxics. It is suited for case studies, air quality assessments, scenarios analyses and pollutants forecast. FLEXPART (Austria/Germany/Norway) – An efficient and flexible Lagrangian particle transport and diffusion model for regional to global applications, with capability for forward and backward mode. Freely available. Developed at BOKU Vienna, Technical University of Munich, and NILU. GRAL (Austria) – The GRAz Lagrangian model was initially developed at the Graz University of Technology and it is a dispersion model for buoyant plumes from multiple point, line, area and tunnel portal sources. It handles flat or complex terrain (mesoscale prognostic flow field model) including building effects (microscale prognostic flow field model) but it has no chemistry capabilities. The model is freely available: http://lampz.tugraz.at/~gral/ HAVAR (Czech Republic) – A Gaussian plume model integrated with a puff model and a hybrid plume-puff model, developed by the Czech Academy of Sciences, is intended for routine and/or accidental releases of radionuclides from single point sources within nuclear power plants. The model includes radioactive plume depletion by dry and wet deposition as well as by radioactive decay. For the decay of some nuclides, the creation of daughter products that then grow into the plume is taken into account. IFDM (Belgium) – The immission frequency distribution model, developed at the Flemish Institute for Technological Research (VITO), is a Gaussian dispersion