Field calibrations of a low-cost aerosol sensor at a regulatory monitoring site in California
Field calibrations of a low-cost aerosol sensor at a regulatory monitoring site in California
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DOI：
10.5194/amt-7-1121-2014
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发表时间：
2014-01-01
影响因子：
3.8
通讯作者：
Seto, E.
中科院分区：
文献类型：
--
作者：
Holstius, D. M.;Pillarisetti, A.;Seto, E.
环境细颗粒物（PM2.5）对健康的影响现在被列为世界上健康负担最重的风险因素之一，但现有的监测基础设施无法充分表征城市PM2.5浓度的时空变化，也无法充分表征人群暴露的时空变化。基于低成本传感器的更便携和负担得起的监测仪器的开发和评价可能提供一种补充和扩大现有基础设施的手段，增加经验测量的密度和覆盖范围，从而改进暴露科学和控制。在这里，我们报告了我们使用低成本、现成的光学气溶胶传感器开发的定制的、电池供电的气溶胶监测仪器的现场校准。在加利福尼亚州奥克兰的一个监管监测点，我们使用美国环保局III类联邦等效方法（FEM） PM2.5 β衰减监测仪连续运行的1小时和24小时PM2.5数据校准了我们的仪器。我们观察到与环境湿度和温度的关联可以忽略不计；线性修正足以解释参考PM2.5 1 h数据中60%的方差和24 h数据中72%的方差。集成时间为1 h时的性能可与成本高得多的商用光学仪器相媲美。这些发现为进一步探索在何种情况下部署这类气溶胶传感器以生成改进的PM2.5数据集提供了依据。
Health effects attributed to ambient fine particulate matter (PM2.5) now rank it among the risk factors with the highest health burdens in the world, but existing monitoring infrastructure cannot adequately characterize spatial and temporal variability in urban PM2.5 concentrations, nor in human population exposures. The development and evaluation of more portable and affordable monitoring instruments based on low-cost sensors may offer a means to supplement and extend existing infrastructure, increasing the density and coverage of empirical measurements and thereby improving exposure science and control. Here, we report on field calibrations of a custom-built, battery-operated aerosol monitoring instrument we developed using low-cost, off-the-shelf optical aerosol sensors. We calibrated our instruments using 1 h and 24 h PM2.5 data from a class III US EPA Federal Equivalent Method (FEM) PM2.5 beta-attenuation monitor in continuous operation at a regulatory monitoring site in Oakland, California. We observed negligible associations with ambient humidity and temperature; linear corrections were sufficient to explain 60% of the variance in 1 h reference PM2.5 data and 72% of the variance in 24 h data. Performance at 1 h integration times was comparable to commercially available optical instruments costing considerably more. These findings warrant further exploration of the circumstances under which this class of aerosol sensors may profitably be deployed to generate improved PM2.5 data sets.