The key anthropogenic pollutants are known to adversely affect global environment and human health. Raising public awareness of such negative impacts, as a trigger, contributes to pay more attention to the underpinning air quality monitoring techniques to acquisition of reliable data on spatial and temporal scale. The sampling techniques are broadly classified into two approaches: currently active air sampling systems (AAS) domain the majority of atmospheric monitoring programs as fix-site regulatory monitoring networks; another alternative approach is passive sampling systems (PAS) without extra pump apply, saving power consumption and space, thus making them feasible for exposure measurement.

This study aims to emphasize the performance of the various manifestations of PAS system in c...[ Read more ]

The key anthropogenic pollutants are known to adversely affect global environment and human health. Raising public awareness of such negative impacts, as a trigger, contributes to pay more attention to the underpinning air quality monitoring techniques to acquisition of reliable data on spatial and temporal scale. The sampling techniques are broadly classified into two approaches: currently active air sampling systems (AAS) domain the majority of atmospheric monitoring programs as fix-site regulatory monitoring networks; another alternative approach is passive sampling systems (PAS) without extra pump apply, saving power consumption and space, thus making them feasible for exposure measurement.

This study aims to emphasize the performance of the various manifestations of PAS system in comparison with AAS deployed indoors and outdoors. Interferences of air turbulence on collection efficiency calculated by an empirical equation for CNPSS and external factors on sampling variation are both recognized. The results showed that the general performance of PAS system is accepted. Measurement distortions can be eliminated or recovered either by providing sufficient air movement or increasing wind velocity. However, continuously increasing wind velocity does not benefit for the accuracy of measurement further optimized. This characteristic of PAS system may have substantial implications for interpretation of measurement consistency with AAS system at stagnant air environment.

On the basis of having concepts of PAS system, a compact and novel diffusion-based monitor for real-time gaseous exposure measurement under various meteorological conditions encountered in Hong Kong, China is evaluated. The results show that this portable diffusion-based monitor’s sensor data are enhanced under in dynamic environments without the need for post processing of data with mathematical algorithms. Additionally, enhanced side-by-side calibration (eSBS) by transfer standard is recommended to address sensor drift problem in the long-term run.