A New Black Carbon Sensor for Dense Air Quality Monitoring Networks.

Julien J Caubel,Thomas W Kirchstetter,Troy E Cados

doi:10.3390/s18030738

Abstract

Low-cost air pollution sensors are emerging and increasingly being deployed in densely distributed wireless networks that provide more spatial resolution than is typical in traditional monitoring of ambient air quality. However, a low-cost option to measure black carbon (BC)—a major component of particulate matter pollution associated with adverse human health risks—is missing. This paper presents a new BC sensor designed to fill this gap, the Aerosol Black Carbon Detector (ABCD), which incorporates a compact weatherproof enclosure, solar-powered rechargeable battery, and cellular communication to enable long-term, remote operation. This paper also demonstrates a data processing methodology that reduces the ABCD’s sensitivity to ambient temperature fluctuations, and therefore improves measurement performance in unconditioned operating environments (e.g., outdoors). A fleet of over 100 ABCDs was operated outdoors in collocation with a commercial BC instrument (Magee Scientific, Model AE33) housed inside a regulatory air quality monitoring station. The measurement performance of the 105 ABCDs is comparable to the AE33. The fleet-average precision and accuracy, expressed in terms of mean absolute percentage error, are 9.2 ± 0.8% (relative to the fleet average data) and 24.6 ± 0.9% (relative to the AE33 data), respectively (fleet-average ± 90% confidence interval).

Highlights

Air quality monitoring networks operated by regulatory agencies traditionally rely on a small number of measurement sites centrally located within large geographical areas
Monitoring at central locations is highly valuable for establishing air pollution concentration trends [4], but pollutant concentrations measured at a single location in a neighborhood or urban area do not necessarily accurately describe the pollution exposures of individuals located throughout that area [5,6]
Aerosol Black Carbon Detector (ABCD)’sdesign designarchitecture, architecture, this paper presents a detailed evaluation of the sensor’s native this paper presents a detailed evaluation of the sensor’s native sensitivity sensitivity to ambient temperature fluctuations, and demonstrates a processing novel datamethodology processing to to ambient temperature fluctuations, and demonstrates a novel data methodology correct this temperature

Summary

Introduction

Air quality monitoring networks operated by regulatory agencies traditionally rely on a small number of measurement sites centrally located within large geographical areas. Monitoring at central locations is highly valuable for establishing air pollution concentration trends [4], but pollutant concentrations measured at a single location in a neighborhood or urban area do not necessarily accurately describe the pollution exposures of individuals located throughout that area [5,6]. Low-cost sensors that measure particulate matter (PM) are available, where mass concentration is typically based on the amount of light scattered by the airborne particles [15,16,17]. Combinations of these low-cost sensors are increasingly deployed in densely distributed sensor networks to provide greater spatial

Methods

Results

Conclusion