Using BREEZE ROADS, users can tailor their analyses for a wide variety of scenarios by picking and choosing from the many advanced features this product has to offer. BREEZE ROADS gives users the ability to estimate queue lengths and emissions contributions from idling and moving vehicles on various types of roadways. A two-tiered approach is also employed in CAL3QHCR that allows for emissions, traffic volume, and signalization to be varied by day of the week.


BREEZE ROADS includes the CALINE4, CAL3QHC, and CAL3QHCR line source dispersion models and a traffic algorithm for estimating vehicular queue lengths at signalized intersections. CAL3QHC and CAL3QHCR are enhanced versions of the CALINE3 model that incorporates methods for estimating queue lengths and the contribution of emissions from idling vehicles. BREEZE ROADS will estimate the total air pollution concentrations from both moving and idling vehicles.

Roadway Types

BREEZE ROADS has the ability to calculate pollutant concentrations on at-grade roadways, depressed roadways, fill (raised roof) roadways, bridges, intersection or queuing links, street canyons, bluffs, and parking lots. A two-tiered approach using the CAL3QHCR module allows for a variation of emissions, traffic volume, and signalization data depending on the day of the week.

ROADS Roadways screenshot

Users have the option to choose from a variety of roadways, and can easily draw these roadways on the base map using CAD-like drawing tools.

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