Whether particles from combustion processes, particulate matter in large cities, viruses in indoor air, or as an object of health research: a wide variety of scientific fields are focused on the smallest particles.
Among the subjects are
Aerosol generators, aerosol spectrometers, measuring instruments in the nano- to micrometer range, filter testing devices: Palas GmbH offers high-precision technology for a wide range of scientific applications
Nanoparticles or UFP (Ultra Fine Particle), i.e. particles with a size < 100 nm, have become subject of numerous investigations regarding their evolution and their propagation.
Measurements at an airport, which were implemented by Palas® with the U-SMPS , show that nanoparticles can certainly be detected even at a greater distance from the point of origin. In this case, the sources of nanoparticles were aeroplanes during take-off and landing. By means of optimised scan times of the measuring device used, individual take-offs and landings of aeroplanes could be verified even at a distance of 400 meters on the basis of the concentration of nanoparticles. The aerosol source was always eliminated when there was no air traffic at night. Here, the flexibility of the measurement system in particular with regard to the measurement duration was a factor for the successful implementation.
In the context of environmental protection, many different scientific studies have been carried out on aerosol dispersion in the ambient air.
The localisation of the aerosol sources and the nature of the aerosol (material, particle size as well as concentration) are decisive. In addition, dispersion and changes due to influences such as wind direction and speed, relative humidity or temperature are considered. To determine these uniquely, measuring instruments with a high size resolution and very good comparability are needed.
The Stuttgart Am Neckartor measurement station is located on a busy main road. The particulate matter levels measured there are among the highest in Germany and are repeatedly a topic in the media. The enclosed publication describes how the effect of the so-called Filter Cubes on the PM fractions can be reliably measured in the area close to the traffic. The mobile aerosol spectrometer Fidas® Frog and the certified fine dust measuring device Fidas® 200 S . are used here. Since both device types have the same detection technology and the same high measurement accuracy, the results determined at different positions can be compared very well with each other.
During the Covid 19 pandemic, among many other restrictions, cultural events were halted because gatherings of people indoors allow the virus to spread.
Researchers are currently studying how aerosol particles released by people into indoor air via respiration spread through the room. Of interest is how the distance to an infected person affects the risk of infection and the influence of measures such as fresh air supply or air filtration. Reliable results require generators that produce aerosol particles with constant properties and measuring instruments that detect them accurately.
The accompanying article presents results of measurements in theaters and concert halls. Test aerosols similar to those emitted by humans were generated with the Palas AGF 2.0ip, which sets standards for consistency and reproducibility. Aerosol dispersion was studied using highly accurate Palas Promo 2000 , Fidas Frog and AQ Guard aerosol spectrometers. Recent developments ( Europa-Park Rust ) show that safe events are possible by systematic investigations.