Fine dust is a danger to human health. However, the fine dust is not only caused by exhaust emissions: each braking action releases particles. In future the new brake dust particle filter from MANN+HUMMEL will retain these emissions directly at the source.

As the level of air pollution worldwide is on the rise, the awareness of risks and consequences to human health is also increasing. Many cities plagued by contaminated air are constantly discussing the causes and possible solutions. Particles with a diameter of less than 10 micrometers (PM10) are particularly dangerous because they can penetrate pulmonary alveoli. Smaller particles than that can even directly enter the blood and cause heart disease and respiratory illnesses.

The focus of current legislation is concentrated on the exhaust emissions of the combustion engine. Other sources of fine dust such as the fine dust generated by brake abrasion have up to now been disregarded to a great extent. In Germany approximately 10,000 tons of brake dust particles are created every year. Measurements on test benches show that more than 90% of this consists of particles with a diameter smaller than 0.55 micrometers. The fine dust pollution is especially high at busy road junctions because at such locations many braking actions are required. But longer visits to underground railway stations can also be harmful to health. Measurements in the London underground system, for example, have registered air pollution with inhalable particles in the range of 500 to 1,120 micrograms per cubic meter. The daily limit specified by the European Union of 50 micrograms per cubic meter is therefore greatly exceeded. But it is not only vehicles with a combustion engine or trains which create the fine dust. In electric and fuel cell cars with no exhaust emissions and stationary engines braking actions also take place which result in the generation of dangerous brake dust.

New Filter

MANN+HUMMEL has developed a new solution for all of these applications in the form of the brake dust particle filter. Located close to the brake and therefore the source, the filter retains the particles which are the result of mechanical abrasion on the brake. The filter consists of a robust housing which is positioned directly in continuation to the brake caliper and captures particles created in the braking process. The new development can be fitted to any existing installation space and can be adapted to different brake sizes and concepts.

The vision is for zero emissions

One of the first field tests for the brake dust particle filter was made in the ‘fine dust eater’ vehicles from MANN+HUMMEL. These vehicles have been on the road for a number of months. Their mission is to retain more fine dust than the vehicles generate themselves. To make this a success, the ‘fine dust eater’ vehicles are equipped with three different types of filter systems: a fine dust particle filter, a new type of NO2 fine dust combi filter for the cabin and a brake dust particle filter. For MANN+HUMMEL this is a further step towards implementation of the vision zero emissions.