Nanoparticle monitoring for exposure assessment

Particulate air pollution comprising inhalable particles with d_p les 10 mum is an important determinant of the severity of the overall air pollution level. Among these, the airborne UFPs and NPs with d les 0.1 - 0.3 mum form a particular class of particles because of recent insights that the particle toxicity per unit particle mass is inversely proportional to the particle size. The toxicity of many engineered NPs is thereby still unknown, thus mandating precautionary measures to reduce personal exposure. In this context, the Aerasense NP monitor is a useful instrument to promote human awareness about the issue of NP pollution, to assess personal exposure, to trace pollution sources, and to monitor the effect of exposure reduction measures. Its output signals allow for a characterization of the encountered NP/UFP pollution level and for a generation of a signal that is foreseen to directly relate to the incurred inhalation- induced health risk. In addition, the NP monitor can be used for early warning purposes and for feedback to actively control the settings and operation of air-handling units and air-cleaning units. This can be used to ensure that the NP or UFP pollution levels remain at all times below certain set concentration levels and that the strategy with which this is done is carried out such that the required energy consumption is minimized. Judicious compromises can then be made between the optimization of the indoor air quality in a variety of environments on the one hand and the incurred energy costs on the other hand.