Background Air pollution from high levels of particulate matter (PM) is a major environmental and health problem in many European cities. Raised levels of these tiny, solid particles in the air are linked to health hazards such as heart disease, breathing problems and lung cancer. The European Commission estimates that the problem causes 300 000 early deaths each year, with the major contributors to PM being motor vehicles - particularly diesel engines - domestic fuel burning, and industry. Such pollution is a special problem in the cities of Klagenfurt, Graz and Bozen (Bolzano) in Europe’s southern Alpine region, which took part in this LIFE project. This is partly because of their geography and climate. In some areas, air pollution has been exceeding the EU limit of 50 µg/m³ for microdust - PM10 - on more than 100 days each winter. Some recorded concentrations have been greater than in densely populated areas such as London. The situation is to some extent alleviated in the summer when warm air and winds lift the particles and distribute them over a wider area, but is at its worst for the six winter months, and re-suspension - the taking up of deposited dust particles from the roads back into the ambient air – is a particular factor. Objectives The “KAPA GS” project had four objectives: 1. To reduce concentrations of microdust with particulates smaller than 10 or 2.5 micrometers - PM10 and PM2.5. 2. To develop simulation models to predict effects of different measures and provide forecasting of PM levels. 3. To inform the public about PM10 concentrations. 4. To carry out a cost-benefit analysis. Results At its conclusion, the project was regarded as a model of best practice - from its administration to its success in achieving nearly all expected results. Reductions in PM concentrations were achieved in a number of areas. Thanks to a statistical forecast model the team can now provide useful forecasts about PM levels a day ahead and take action to reduce them. Work began with establishment of air-quality-monitoring and particle-dispersion models. Methods of reducing PM emissions - such as driving bans or restrictions - were simulated. Forecasting models were set up for the project locations using traffic patterns and weather conditions. Actual PM values were monitored and a new measurement instrument developed. The result was dubbed “Nowcasting” giving an accurate current and future picture of PM levels. Street closures and other traffic restrictions were put in place when levels demanded. Eight large indicator boards beside access roads into Klagenfurt informed the public about current PM ratings and restrictions. A red, yellow and green display was used to show PM status. To decrease car numbers, bus-ticket prices were reduced in some areas and park-and-ride systems established; September 22 each year is a car-free day in Klagenfurt and Graz. To promote acceptance of these measures, a PR campaign was launched. To reduce the amount of PM from public transport, 114 city buses in Graz were adapted by “retro-fitting” particle oxidation catalysts, achieving a 70% reduction when used with bio-diesel. In Klagenfurt, 15 buses were fitted with particle filters, achieving a near-100% reduction. The project identified that 26% of PM in winter arises through re-suspension of particles from the streets. New road-sweeping machines were tested using more efficient technology, generating lower emissions. Gritting was abandoned and moist salt used in place of dry. Applying calcium magnesium acetate (CMA) in place of salt every second day was found to reduce re-dispersion by 48%. A higher level could be achieved if used each day, but with corresponding cost increases and there is an issue with CMA causing slippery surfaces. Pollution from individual carbon-based domestic-heating systems was addressed in Klagenfurt through a programme of publicity and financial subsidy to encourage connection to the district heating system or to natural gas. During the project, 101 new connections were made and a further 700 are planned. Reductions achieved at the end of the project were: Retro-fitting of catalytic converters in Graz: - 1 400kg PM10/year Retro-fitting of particle filters in Klagenfurt: -182 kg PM10/year New district heating and natural gas connections: -811 kg PM10 /year Optimised winter services (roads) - 1-2µg PM/m³ annual average Shuttle bus: -7.5 kg PM during the project period.With no increase in traffic volume, Klagenfurt could achieve all days under the PM limit by 2020. It is now considering whether to introduce a toll for drivers. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section). This project has been selected as one of the 17 "Best" LIFE Environment projects in 2008-2009.