This paper highlights advantages and drawbacks due to the use of portable and low-cost devices for aerosol sampling, showing their performances during an aerosol monitoring campaign with the parallel use of the gravimetric sampling reference method and a cascade impactor. A specific monitoring campaign was held running all instruments in parallel in indoor, confined, and outdoor environments characterized by local emission sources or particulate matter background concentrations. PM_2.5 concentrations were used to compare data emerging from the different instruments adopted. Significant underestimation of PM_2.5 emerged when comparing data coming from optical sensors with those estimated by the cascade impactor, whose data resulted in being coherent with gravimetric determination, integrated over the same sampling time. A cause–effect relationship between PM_2.5 concentrations and specific emission sources was found when observing the daily patterns of all the real-time sampling devices. It emerged that optical devices are useful for detecting concentration trends, the presence of peak values, or changes in the background value, even if with limited accuracy and precision. The comparison with particle size distributions obtained by the cascade impactor data allowed us to define which particle sizes are not detected by different optical devices, evidencing a low representativeness of optical low-cost sensors for health exposure measurements. The correlations among the specific particle size fractions detected by the cascade impactor and their specific emission sources were particularly high for car emissions in a semi-confined garage area.

中文翻译：

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以特定排放源为特征的室内，密闭和室外环境中综合气溶胶采样技术的评估

本文重点介绍了由于使用便携式低成本设备进行气溶胶采样而带来的优缺点，并展示了它们在气溶胶监测活动中与重力采样参考方法和级联冲击器并行使用的性能。在室内，密闭和室外环境中，以本地排放源或颗粒物背景浓度为特征的所有仪器并行运行，开展了专门的监测活动。使用PM _2.5浓度比较采用的不同仪器产生的数据。严重低估了PM _2.5当将来自光学传感器的数据与级联撞击器估算的数据进行比较时，出现了这种情况，级联撞击器的数据导致在相同的采样时间内与重量测定相一致。PM _2.5之间的因果关系观察所有实时采样设备的日常模式时，发现了浓度和特定的排放源。已经发现，即使具有有限的精度和精确度，光学装置也可用于检测浓度趋势，峰值的存在或背景值的变化。通过级联撞击器数据获得的粒度分布的比较，我们可以定义不同的光学设备未检测到哪些粒度，这证明了用于健康暴露测量的光学低成本传感器的代表性较低。对于半封闭车库区域中的汽车排放而言，级联撞击器检测到的特定粒度分数与其特定排放源之间的相关性特别高。