Empirical evaluation of electrochemical air pollution sensors
Citation:
O'Regan Murphy, Mark Edward, Empirical evaluation of electrochemical air pollution sensors, Trinity College Dublin.School of Engineering, 2022Download Item:
morm_08819858_final_double_sided.pdf (Accepted for publication (author's copy) - Peer Reviewed) 35.81Mb
Abstract:
The objective of the research was to characterise the potential of state-of-the-art low cost gas air pollution sensors to measure air pollution levels in an active urban environment, through the implementation of a set of evaluation methodologies which included the construction of a monitoring device, calibration procedures and co-location studies at active government operated reference air quality sites in Dublin.
Air pollution is presently the largest growing environmental concern, as such it has driven the instigation of numerous directives and guidelines aimed towards mitigating this issue. These recommendations consist of identifying and reducing the main pollution sources, through methods such as monitoring. While most European cities already meet the requirements stated in the EU directive 2008/50/EC, the identification of pollution sources remains challenging. This is tied to the sparse number of monitoring sites owing to the large associated costs and physical implementation barriers of the currently approved measurement methods. The recent emergence of high performance low-cost sensors targeted towards air pollution monitoring has provided potential for effectively increasing point measurement density in urban areas.
The work was conducted by evaluating 4-electrode amperometric gas sensors, designed for measuring low-level concentrations of four main air pollutant gases, versus known gas concentration exposure conditions in laboratory settings and versus SI reference devices in deployment case studies. A set of different evaluation methods were constructed in order to provide a full monitoring system layout. These included the construction and validation of a novel air pollution monitor, an integrated calibration methodology including an automated analysis and an automated deployment analysis, all aimed at identifying cross-sensitivities and performance metrics.
The results indicated that the selected electrochemical gas sensor could provide good concordance with reference measurements when concentrations are greater than their lower limit of detection. These also demonstrated that the sensor?s low level sensitivity decreases with time but that exposure to a regulated flow rate increases accuracy and consistency.
A further observation was made as to an apparent failure mechanism of such gas sensors, which would allow the determination of the health of the sensor directly in the field, without the use of external cross reference data. Meticulous implementation methods of low-cost gas sensors, combined with the use of sensor arrays incorporating different technologies, has clear scope for meeting regulatory measurement standards.
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Dublin City Council
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https://tcdlocalportal.tcd.ie/pls/EnterApex/f?p=800:71:0::::P71_USERNAME:OREGANMMDescription:
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Author: O'Regan Murphy, Mark Edward
Advisor:
Geraghty, ThomasPublisher:
Trinity College Dublin. School of Engineering. Discipline of Mechanical & Manuf. EngType of material:
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