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Transport management


Dealing with air pollution from mobile sources requires an integrated approach involving

  • good transport planning including Travel Demand Management (TDM) and Transport Systems Management (TSM)

  • the setting of standards for clean fuels and vehicle emissions and to encourage clean new vehicles

  • and effective inspection and maintenance of the in-use fleet

Significant political will and technical capacity is required for implementation and vigorous efforts should be made to create both.

Care will be required to ensure that the poor people are benefited by actions to improve air quality and not displaced or unfairly disadvantaged.


"Transport planning" is defined as the objective analysis of travel demand and socio-economic/ land use factors giving rise to that demand, the formulation of improvement alternatives that address explicitly stated improvement objectives, the formulation of a recommended set of activities to realize stated objectives as well as the regular monitoring and evaluation of those objectives and activities. It is multi-disciplinary in nature. Ensuring that development is sustainable requires a focus on mobility of people and goods, not vehicles. Appropriate objectives should include ensuring that recommendations support sustainable development including improved air quality and ensuring access to jobs and the goods and services that people need.

"Travel Demand Management" (TDM) aims to influence demand and indirectly supply to manage congestion and minimize vehicle-kilometers of travel in the short and long terms. Ideally, TDM should be integrated with all aspects of transport planning. In so doing, TDM needs to address the appropriate roles for buses, cars, non-motorized vehicles (NMVs), walking and other modes.

"Transport Systems Management" (TSM) aims to make best use of existing infrastructure and concentrates on managing person-movements rather than vehicle flows. TSM is usually implemented in tandem with TDM.

  • Transport planning should be integrated with comprehensive planning for land use and air quality.

  • Transport planning should seek to influence both demand and supply to achieve societal objectives including that of improving air quality.

  • All plans and projects should be based on appropriate levels of consultation with transport system users and other stakeholders. They should benefit rather than disadvantage the poor.

  • Implementation of sustainable transport and associated plans requires strong leadership, good coordination and integrated institutional responsibilities for air quality and transportation.

  • Public transport should be promoted in preference to private modes by formulation of soundly based policies and projects.

  • Support to create clean public transport vehicles should be carried out within the framework of an appropriate regulatory and franchising regime that takes into account the capacity of public transport operators to finance improvements on a sustainable basis.

  • Better pricing of transport, in particular, to ensure car and motorcycle drivers correctly perceive the full costs of their travel decisions is required.

  • Setting of improvement priorities should be carried out on an objective basis taking into account of all relevant costs and benefits including social and environmental effects.

  • Plans should protect the existing role of non motorized vehicles and pedestrian movements and encourage the expansion of this role where beneficial.

  • Use of planning tools, data and models verified for Asian city use should be used for plan formulation and as an to aid decision making.

  • Creating the political will to improve air quality requires: public awareness, then influencing of public attitudes through communication of accurate information on health impacts, and an open media and process of public hearings.

  • As there is much to do and many urgent priorities, reliance on government agencies alone for implementation is not recommended. Innovative approaches harnessing the private sector, non-government organizations and other groups should be developed.


Transport's contribution to air pollution is a serious and growing issue because

  • transport or mobile sources contribute the majority of most pollutants in urban areas particularly when viewed in terms of human exposure

  • transport contributes the vast majority of the increases in urban air pollution

  • emissions of most pollutants greatly increase as vehicle speeds fall

  • Asia's large cities are plagued by growing traffic congestion with a temporal and geographic expansion of that congestion

  • previous studies have shown that without good transport planning and management total emissions will rise even with other improvements.

In Asia, studies have confirmed that the main pollutant of concern is particulate matter (PM) especially very fine PM , which has serious proven health impacts. Other pollutants, such as nitrogen dioxide and ozone, also warrant serious attention.

Even though air pollution may have regional and global implications the most direct and severe impact is on human health and this impact is highly location specific. For example, in Asia with the high levels of human activity in and around transport corridors the incidence of people suffering health damage is very high.

Asia's cities have diverse motorization experiences, transport modes and socio-cultural environments. Within cities different road users have different needs that are frequently conflicting.

Finally, there is a lack of knowledge on how best to address motorization and associated problems that is locally appropriate. To date, there has been a reliance on western experience. Undertaking relevant local research activities and data collection to formulate appropriate planning methods and models is required.

  • Urbanization is rapidly increasing throughout Asia. And urban growth is largely unplanned.

  • Economic growth is associated with growth in vehicle traffic in the minds of decision makers. This prevailing mind-set sees car ownership and use as highly desirable and a status symbol.

  • Many cities in Asia have implemented traffic management measures with mixed success. In many cases, there are inadequate resources to maintain these schemes and they are abandoned.

  • Noise from transport sources is also an issue in many of Asia's cities.

Go to the BAQ 2004 website
Vehicular air pollution > Transportation and traffic management

Secretariat: The World Bank & Asian Development Bank