The National Centre for Scientific Research “Demokritos” is the biggest and most acclaimed research center in Greece, employing over 1,000 researchers, engineers, technicians and administrative personnel.

The DETRACT atmospheric dispersion modelling system, developed by the EREL, is an integrated set of modules for modelling air pollution dispersion over highly complex terrain.

The modules included in DETRACT include:

* Topography and land use pre-processors that prepare the ground-related inputs for the other modules.
* A meteorological pre-processor to generate meteorological data.
* A module for generating wind fields.