National air pollution control
On January 1, 2005, the European limits for fine particulates (PM10) came into force with the 22nd Federal German Immission Protection Order. These limits regulate dusts with a maximum particulate diameter of 10 mµ (= one hundredth of a millimetre). The mean daily value for these particulates (PM10) should not exceed 50 µm per cubic metre of air. In accordance with the EU Directive, this value can be exceeded 35 times in a calendar year. In addition to the daily value, there is also a mean annual value of not more than 40 µg per cubic metre of air. Target values for NO2 of 50 µg per cubic metre have also been introduced.
In 2005, a total of 34 municipalities, including the city states of Berlin, Bremen and Hamburg, reported more than 35 exceedances of the mean daily value. Of the remaining towns, six were in Saxony, five in Bavaria and Baden-Württemberg, four in North-Rhine Westphalia, three in Hesse, two each in Lower Saxony, Rheinland-Palatinate and Brandenburg and one each in Saxony-Anhalt and Thuringia. No exceedances of the 35-day limit were reported in Saarland, Mecklenburg-Western Pomerania and Schleswig-Holstein.
In 2005, the temporary measuring station at Stuttgart-Neckartor recorded the most exceedances of the mean daily value – a total of 181 – followed by Leipzig-Mitte and Munich-Landshuter Allee. Even the North Sea island of Norderney reported eighteen such exceedances.
After one year’s experience with the new values, the enormous influence of meteorological factors is becoming ever clearer. Exceedances of the mean daily value usually only occur during the winter months. As a rule, exceedances can be observed simultaneously over large areas. This goes hand-in-hand with high-pressure or inversion weather patterns. This has been confirmed by the German Government, which has stated that 70 percent of the exceedances were reported during weather patterns with poor airflow. However, vehicle traffic is there all the time. Furthermore, high immissions can be measured during periods of no precipitation since the precipitation itself and the duration of the precipitation have a considerable influence. In Dresden-Nord, between 2001 and 2002, for example, particulate concentrations in the air were measured during dry periods and during precipitation. When there was no precipitation, values of more than 35 µg per cubic metre were attained. When there was precipitation, they fell to 12 µg per cubic metre. The Fraunhofer Institute in Dresden (IVI) states that the proportion of PM 10 attributable to transport is relatively constant and is normally less than 8 µg per cubic metre at street measuring stations.
Having exceeded the average daily values, many German cities have already decided to introduce air pollution control plans or even adopted some of the measures they involve. The Bavarian Administrative Court of Appeal recently reached a verdict stating that the authorities must draw up plans of campaign within a reasonable time to lower fine dust levels if these have been exceeded. However, it is not compulsory for such plans to ensure that the limit values are reached, and the authorities have a free choice of the tools they can adopt. In this verdict the Court accepts scientific knowledge to the effect that measures limited to small areas have no significant effect on the PM 10 level. Frankfurt am Main is one such example. Here one trunk road was closed off to commercial vehicle through-traffic, gateway traffic lights were installed and measures to improve traffic flow were implemented. Despite the much lower volume of traffic during the holiday period around New Year, by the beginning of January the mean daily value was already being exceeded at the measuring point; the New Year fireworks alone in the early hours of January 1 caused peaks of 350 µg per cubic metre. Further peaks of up to 200 µg per cubic metre and more were recorded at the weekends. It is quite obvious that vehicle traffic cannot be contributing significantly to these exceedances.
Similar figures were reported in Switzerland. When air pollution increased, the Swiss authorities lowered the speed limit on motorways from 120 to 80 kilometres per hour. As the Swiss measuring institutes found, this measure succeeded in reducing the proportion of fine particulates measured at street level by 10 percent. At the same time, however, road traffic volume fell by around 15 percent. In addition, the Swiss also noted that emissions from domestic open fires were contributing just as much to fine particulate levels as road traffic did as a whole.
In Germany, like in Switzerland, fine particulate emissions from house fires are more significant than engine emissions from road transport. The Federal Environment Agency states in its current background paper that in the one year, from 2002 to 2003, fine particulate emissions from vehicle engines fell by more than 10 percent and in 2003 totalled just 22.7 kt. This figure will fall even more, and on a continual basis, as more and more diesel particulate filters are introduced. This figure of 22.7 kt from engine emissions contrasts with the 24 kt attributed to small wood fires. Consequently, wood fires are emitting more than all the engines from road transport.
What was tantamount to a large-scale trial took place last year in the Rhine/Main area, during the visit of US President George W. Bush. On this day, the centre of Mainz and the southern suburbs of Wiesbaden were practically traffic-free. Though the levels recorded for the Rhine/Main region were lower on that day, this was due to the general weather situation. This reduction was observed in the whole of the southwest region, in other words in regions not affected by the traffic restrictions. Consequently, when taking a year’s experience into account, it can be seen that closing off roads and other such traffic restrictions do not have any significant effect on the levels of fine particulates in the air.
Thanks to air pollution control measures, dust and fine particulate pollution has been falling sharply and continually for a number of years. In Switzerland, for example, levels fell by around a third between 1999 and 2000. This downward trend is continuing.
The German automotive industry – leading the way with diesel particulate filters
Over the past few years, soot emissions from diesel vehicles have already been reduced significantly. The filters available today lead to an almost hundred-percent reduction in particulates in exhaust gases. In 2004, German car manufacturers issued a clear signal in favour of the installation of soot filters with the worldwide unique "Stuttgart Declaration". In it, they announced that, by 2008/09, they would offer a diesel particulate filter on all vehicles sold in Germany. This goal will be achieved considerably earlier.
Around two years have passed since the Stuttgart Declaration on the introduction of diesel particulate filters, so it is a good time to assess the effect of the declaration. And the results can be clearly seen. More than 60 percent of newly registered diesel passenger cars in Germany are now fitted with particulate filters, three times more than just one year before. There will soon be 250 models available with particulate filters. At the beginning of 2006, the market share of German brands was 84 percent, while French brands had a 14 percent share, and the rest of the market share was held by Asian and other European suppliers.
Retrofit programmes are underway as well. At the end of 2005, the second chamber (the ‘Bundesrat’) adopted the technical regulations for retrofitting particulate reduction systems. This establishes the basic pre-conditions for any promotion of diesel particulate systems through tax incentives.
The German automotive industry offers retrofit filters for any existing diesel vehicles. However, it is becoming increasingly evident that customers will not opt for retrofit kits in any great numbers unless the kits are also promoted by means of tax incentives. Although the government has often spoken of such a promotion, up till now there has been no implementation. It is not yet clear whether this will take place during 2006 and begin to exert an effect before the end of the year. The automobile industry fears that promotional models may be considered that could lead to an increased burden on the car owner.
The German automotive industry will continue to play an active part in the reduction of emissions. It should not be forgotten, however, that other sectors are also obliged to reduce their emissions to technically and economically feasible levels. If wood fires contribute more to fine particulate pollution than road transport as a whole, it is clear that this area needs to be looked at.
