Information on fine dust

1. What is fine dust or particulate matter?

Science distinguishes between various forms of fine dust, which differ from each other mainly in the size of the particles. The smaller the particles, the more dangerous they are. While coarser particles are filtered during inhaling– for examples by the nasal hairs – small particles are able to pass and make their way directly into the lungs. Fine dust consisting of such small particles is called PM10. This means that the particles are smaller than 10 micrometres, which is smaller than 1 hundredth of a millimetre. This is why the limit values set by the EU and our air-quality measurements relate to these PM10 particles


2. What and where are the origins of fine dust?

First of all, fine dust arises wherever and whenever something is burnt, i.e. in automotive engines, in industry and in heating systems. Secondly, fine dust is generated when coarser parts are ground into smaller ones, i.e. by tire abrasion and abrasion of brake linings or by the crushing of gravel. Since the dust is fine, it does not settle to the ground at its source, but is raised and spread over large areas. While petrol engines emit very little particulate matter, diesel engines are considered to be  he biggest polluter in this respect. All in all, it is believed that at least 70 % of fine dust originates from these sources.

3. Where are the limit values?

Limit values can be defined once there is scientific evidence in what way a certain substance affects the human organism and in which quantity a substance does not cause any harm. This means that a health hazard can be scientifically excluded if the limit values are not exceeded. Starting in 2001, measuring of particulate matter and setting limits for ist concentrations were begun throughout the EU. Annual mean value: 40 µg/m³, daily mean value: 50 µg/m³. Since there doesn’t exist a “no effect level” for particulate matter, its concentration must be kept as low as possible.

4. How is particulate matter measured?

The responsible departments of the Carinthian Government as well as the Department of Environmental Protection of the City of Klagenfurt try to determine particulate emissions as realistically as possible. It is obvious that the measured particulate burden can be influenced by the choice of the measuring location.
Naturally, green belts and low-traffic zones are less affected than main roads. The fine-dust burden is therefore measured at critical points.

5. Particulate matter, geography and the weather

Particulate matter is produced not only in winter but throughout the year. Nevertheless, pollution is considerably higher in winter than in summer. This is mainly due to the geographical location of cities in basins and the winter weather.
In summer, the air near the ground is heated much more strongly in cities, rises and is spread over large areas by the wind. As the fine dust rises with the warm air and is dispersed, the pollution is relatively low in the city.
In winter, a layer of cold air develops in basins and traps the air, which accumulates more and more fine dust. The particles can only be removed by strong winds, which are rare, and precipitation (rain or snow). Also, more particulate matter is emitted in winter (heating, grit) than in summer.

6. Particulate matter: A health hazard

Through inhalation, the fine particles migrate all the way to the smallest air cells in the lungs, the alveoli. Short-term high particulate loads clearly impair pulmonary function and cause or worsen diseases such as asthma. Persons, in whom the body’s own immune system is weakened, such as children, persons suffering from an illness or elderly persons, are more susceptible than others. Studies have shown that long-term exposure to fine dust increases the risk for stroke, lung cancer, cardio-pulmonary diseases and respiratory diseases (e.g. chronic bronchitis).

Below there are some suggestions of how you, as a private person, can contribute towards reducing fine dust:

  • Switching to other means of transport such as bikes, buses, trams, walking, roller skates, etc.
  • Many journeys by car can be avoided by careful planning – e.g. write shopping lists and plans your shopping tours carefully – if you don’t forget anything, you don’t have to make another trip!
  • Educate your children towards soft mobility!
  • Share car trips with colleagues, friends and neighbours, not just for professional but also for leisure-time or shopping trips
  • Exchange fleet vehicles for vehicles with particulate filters, electric – or gas vehicles
  • If your old heating system is still fuelled, e.g., by wood or coal, convert it to use a form of energy which is more environmentally friendly (e.g. natural gas or district heat). This will not only improve air quality, but help you reduce you heating bill and reduce energy consumption as well!