Introducing the RZ model for definition and optimization of the boundary of low emission zones

Abstract

Poor urban air quality is one of the most pressing environmental problems, and the rapid growth in the number of motor vehicles is a major contributor to it. To tackle this problem, low emission zones (LEZs) were introduced and they have been applied in many of the mega cities around the world. Yet, a scientific approach to design the boundaries of LEZs is missing. This study develops an innovative model to address this gap, using total vehicle kilometers traveled (VKT) as the basis. The model allows defining and/or optimizing the LEZ boundaries. It is applied for the Tehran metropolitan area, as a case study, and the results show the optimality of the existing LEZ boundaries; however, they challenge the efficiency of the proposed policies on modifying current boundaries.