Overview of Measures

A wide range of measures can be taken to improve air quality. We have selected nine categories of measures based on their potential to reduce particulate matter (PM10) and nitrogen dioxide (NO2), pollutants for which the EU sets limits for local concentrations. The commitment to reduce these is a major motivation behind most cities’ air quality strategies. The categories have also been selected based on their potential to reduce soot emissions from traffic and non-road pollution sources. The purpose of the ranking is not to measure the reduction potential of the different measures. The aim is to highlight best practices and assess which of the 23 selected cities have made most use of them. Several measures address the main emitters at source, for instance by introducing Low Emission Zones and cleaning up public vehicles fleets or non road mobile machinery such as construction machines. Other strategies such as economic incentives, traffic management, and promotion of cycling and walking may reduce car use and thus improve air quality. In addition, we looked at the reported reduction of local PM10 and NO2 emissions between 2008 and 2012 as well as at the level of public information and citizens’ participation in decision making.


Reduction Success Local Emissions

Background concentrations of PM10 can’t be much influenced at city level and requires national and even internationally coordinating action. However, local traffic is responsible for a significant amount of PM10 concentrations leading to violations of EU limit values. We therefore compared the reported data of traffic stations and background station between 2005 and 2009 …
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Low Emission Zones & Bans of High Emitters

Local Emissions Zones (LEZ) can be an effective way of reducing PM10 and soot emissions. To be effective, a LEZ must be introduced early enough, should be big in size, set ambitious emissions standards (Euro 4 and better) and be strictly enforced. Bans of high emitters have the risk of only relocating pollutants but not reducing them.
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Public Procurement Clean Cars

Municipal vehicles and buses cover big distances in cities and thus become a relevant emission source. They can also serve as a role model by setting the example. Retrofitting existing vehicles by diesel particulate filters (DPFs) and furnishing new ones with effective filters or other clean technologies would help reducing their emissions …
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Non-Road Mobile Emission Sources

Non Road Mobile Machinery (NRMM) is a major emission source which is often overlooked. In some cities, it is responsible to up to 30% of traffic pollution. Construction machines are in use many hours every day and extended time periods. Vessels and railways are other emitters which should be equipped with particle filters if they operate in cities …
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Use of Economic Incentives

Road or congestion charges have proved to lead to important reductions. Revenues can be used for investments in environmentally friendly modes of transport. Other economic incentives can also be introduced through parking management.
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Traffic & Mobility Management Incl. Modal Split

What has been the modal split trend during the last five years? The ranking looked into reductions of personal motorised transport as well as possible targets for the coming years. Some cities are developing innovative mobility management measures aimed at citizens but also companies, schools or universities …
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Promotion of Public Transport

Measures to raise the share of public transport can reduce car use and improve air quality. The ranking looked into investments for expansion of public transport networks and other tools promoting public transport. We looked at the measures implemented over the last five years as well as solid plans to do so in the future …
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Promotion of Walking & Cycling

Hard (infrastructure) and soft (communication) measures were looked into and compared. We assessed whether the measures were ambitious enough and whether their success was documented. We considered future plans when they were concrete with solid political and financial support …
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Transparency & Communication Policy

This category looks both at the public participation in decision making and the level and quality of information available to the public. The level and quality of information was assessed based on wide range of criteria e.g. whether online information tools were sufficient and updated or whether air quality plans were easily accessible. Public participation in decision making has also been assessed.
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