SUMMARY
More than 20 real time transport and dispersion models were applied to a 3 fictitious releases and the results compared. The novelty of the system is that the results all communications, model results acquisition and inter-comparison are performed by means of a web-based system. Through this system the modeling groups spread around the world are informed of the occurrence of an accident, can perform a forecast of the dispersion, submit the results to JRC Ispra and, in few hours, look at the result of the model Inter-comparison.