Many studies have shown that air pollution affects people's health. This paper describes the results of a project to use Urban Traffic Management and Control to manage vehicle emissions. Modelling showed that several key strategies applied in large urban areas could have an effect on vehicle emissions, such as efficient signal co-ordination, road pricing and queue relocation. The effect of the strategies applied with different levels of severity were estimated. Some of the strategies require a high impact to motorists to produce a significant impact on the level of emissions. This is likely to be unpopular with motorists. On-street trials tested the benefit of queue relocation. Queues were relocated through gating, controlled by traffic signals. This aimed to reduce emissions in sensitive areas at the expense of increases in areas where less people would be exposed to the pollutants and natural ventilation would reduce the impacts. Results showed that during the 2 hour peak period emissions were reduced in the protected areas by 3% to 10% according to pollutant. Further analysis showed that during the peak quarter hour within the morning peak the reductions were almost twice as great as the reductions in average values. The queue relocation trials showed that if suitable sites were available to store the relocated queues emissions could be successfully relocated.
Abstract