General measures like speed limits or laws against combustion engines and oil heating systems to meet the PM limits can be accompanied or avoided by the reduction of pollution from specific sources or for example dynamic traffic management. To reduce emissions from specific sources, PM levels have to be collected on a fine grid, the particle sources need to be identified and analyzed and PM distribution mechanisms have to be understood. Dynamic traffic management based on PM levels even needs real-time measurements.
Public agencies investigate PM values using scientific instruments which come with considerable investments and installation thresholds. Such measurements are suitable for point-wise investigation of PM in a coarse measurement network. Already a few streets away from the measurement location strong deviations are possible – depending on topography, buildings, wind or PM sources. For locations that were not selected by public agencies, the closest measurement values may already be invalid and even many kilometers away.Solution
As a solution to this, much cheaper but still sufficiently accurate PM sensors are needed that can be installed easily and everywhere. Such devices can be used to provide a finer measurement grid for local information about the air pollution – leading to widespread knowledge of the local immission file:///A:/Marketing/Ago/14%20Stories-PR-Presse-Kombis/Feinstaub/Meteorological%20Technology%20International%20_%202023.docx#_msocom_1
and enabling distribution studies as well as source identification. At the same time, the measurements have to be reliable even if the scientific precision is not reached to the core.Methods for measuring particulate matter
Classically, particulate matter is measured by deposition of particles on a filter. The filter is usually exchanged on a daily basis, dried and weighed in a laboratory. The relevant measurement values are consequently recorded as micrograms of dust on the filter per cubic meter of filtered air. Information about the chemical substances involved is not obtained regardless of the potentially different impact on the human body. The PM classes are derived from separation of the dust sizes by inertia-based impactor filters. The dust particles with diameters up to 2.5 microns in PM class 2.5 are also included in the fraction PM10.