AERMOD is a "new generation" air dispersion model. AERMOD was promulgated as a preferred regulatory model in the U.S. in the Federal Register on 11/9/2005, with an effective date of 12/9/2005. AERMOD should be used for all applications for which ISCST3 was previously used. The AERMOD System consists of the AERMOD model, its meteorological preprocessor, AERMET, its terrain preprocessor, AERMAP, and the screening model AERSCREEN.
PLEASE NOTE: AERSCREEN replaced SCREEN3 as the screening model for AERMOD as of its release in March 2011. SCREEN3 is no longer the recommended screening model for AERMOD.
Link to EPA SCRAM website for all codes and documentation for the AERMOD modeling system.