Attention risk assessors! It's time to move to the AERSCREEN air dispersion model

摘要

AERSCREEN is now the USEPA's recommended screening-level air dispersion model for regulatory modeling applications. AERSCREEN has enhancements for building wake, terrain elevations, and meteorology that make it more accurate and site-specific than its predecessor, the SCREEN3 model. AERSCREEN can be tedious to use. This study presents a framework to help a novice user quickly set up and execute the public domain version of AERSCREEN. The AERSCREEN and SCREEN3 predictions were compared in an example for a simple vertical point source. The AERSCREEN predicted maximum concentrations were up to six times higher than the SCREEN3 predicted maximum concentrations using the building downwash option and up to nine times higher with no building downwash. The key to having acceptable air dispersion modeling results is to follow a proper protocol. AERSCREEN should be used so the protocol is consistent with US EPA guidance; this may reduce the review time and the effort.