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Title: User's guide to CAL3QHC version 2. 0: A modeling methodology for predicting pollutant concentrations near roadway intersections

Technical Report ·
OSTI ID:6210230

CAL3QHC is a microcomputer based model to predict carbon monoxide (CO) or other inert pollutant concentrations from motor vehicles at roadway intersections. The model includes the CALINE-3 line source dispersion model and a traffic algorithm for estimating vehicular queue lengths at signalized intersections. CAL3QHC enhances CALINE-3 by incorporating methods for estimating queue lengths and the contribution of emissions from idling vehicles. The model permits the estimation of total air pollution concentrations from both moving and idling vehicles. It is a reliable tool for predicting concentrations of inert air pollutants near signalized intersections. Because idle emissions account for a substantial portion of the total emissions at an intersection, the model is relatively insensitive to traffic speed, a parameter difficult to predict with a high degree of accuracy on congested urban roadways without a substantial data collection effort.

Research Organization:
Environmental Protection Agency, Research Triangle Park, NC (United States). Office of Air Quality Planning and Standards
OSTI ID:
6210230
Report Number(s):
PB-93-210250/XAB; EPA-454/R-92/006
Resource Relation:
Other Information: See also PB--85-211498 and PB--93-105559
Country of Publication:
United States
Language:
English