Aerosol particles are a key component of Earth’s atmosphere, affecting human health, climate, and radiation balance. They enter the atmosphere through direct emissions or form from gaseous precursors. Under favourable conditions, molecules cluster together, growing into aerosol particles. These clusters vary in concentration throughout the day, forming in the morning and either growing or disappearing.\nHowever, the exact processes behind the new particle formation (NPF) remain unclear. The NPF events significantly affect the particle concentration in the atmosphere. NPF depends on environmental conditions, for example gaseous precursors, UV radiation, precipitation, wind speed and direction, atmospheric boundary layer characteristics, and the origin of interacting air masses. There is quite a small number of devices able to measure small particles, such as 1 nm in diameter, which are able to monitor the beginning of the NPF event, for example, PSM (Particle Size Magnifier) or nanoSMPS (nano Scanning Mobility Particle Sizer) measuring all particles regardless of their original charge. NAIS (Neutral and Air Ion Spectrometer) is able to measure neutral particles and also charged clusters, giving the idea about the charge distribution in the atmosphere.