Characterisation and enhancement of low-cost optical particle counters for air pollution monitoring in diverse environments

可吸入颗粒物(PM)是全球关注的健康问题，也是发病率和死亡率的重大环境风险因素，对发展中国家、妇女和儿童的影响不成比例。准确测量PM是一项技术挑战。当前的方法需要大量的资源来维护，现代分析方法无法检测城市环境中PM浓度的空间不均匀。技术进步使检测方法微型化，降低了成本，增加了便携性。因此，有可能增加空间和时间测量。实验室和现场对低成本光学粒子计数器(OPC)的评估显示，来自气象变量(如相对湿度)和物理化学变量(如化学成分和粒度分布)的显著伪影。这些变量可以在城市环境中的短距离内变化，该项目旨在针对不同环境中的一套最先进的参考仪器来表征低成本的OPC。伦敦有两个大气超级站点，允许在路边和城市背景位置同时进行唯一的评估。此外，一场室内运动将在一处住宅内进行。这将独一无二地提供OPC技术将接触到的一系列不同的土壤物理和化学性质。将寻求一个国际地点来评估OPC在各种不同的处理环境中所面临的纠正算法和问题。上述方法将全面描述三种不同的低成本OPC在它们最可能所处的环境中的特征。该项目将提供一种基于气溶胶化学的新型校正算法，并为这项新技术的未来评估提供基于证据的建议。

Respirable particulate matter (PM) is a global health concern andlarge environmental risk factor for morbidity and mortality whichdisproportionately affects developing countries, women andchildren. Measuring PM accurately is technically challenging.Current methods require significant resources to maintain andmodern analytical methods are unable to detect the spatialinhomogeneity of PM concentrations in urban environments.Technological advancements have miniaturised detection methods,reduced costs and increased portability. Therefore, there is apotential for increased spatial and temporal measurements.Laboratory and field evaluations of low-cost optical particlecounters (OPC) show significant artefacts from meteorologicalvariables such as relative humidity (RH) and physicochemicalvariables such as chemical composition and size distribution. Thesevariables can change over short distances in urban environmentsand this project aims to characterise low-cost OPC's against a suiteof state-of-the-art reference instrumentation in diverseenvironments.London has two atmospheric supersites that's allows for evaluationto uniquely take place concurrently at kerbside and urbanbackground locations. Additionally, an indoor campaign will takeplace at a dwelling. This will uniquely provide a diverse range ofaerosol physical and chemical properties that the OPC technologywill be exposed to. An international location will be sought to assessthe correction algorithm and issues facing OPC's in diverse andextreme environments. The above approach will provide a fullcharacterisation of three different low-cost OPC's in environmentswhere they are most likely to be situated. This project will deliver anovel correction algorithm based on aerosol chemistry as well asevidence-based recommendations for future assessment of thisnew technology.