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Characterisation and calibration of low-cost PM sensors at high temporal resolution to reference-grade performance.

ABSTRACT: Particulate Matter (PM) low-cost sensors (LCS) present a cost-effective opportunity to improve the spatiotemporal resolution of airborne PM data. Previous studies focused on PM-LCS-reported hourly data and identified, without fully addressing, their limitations. However, PM-LCS provide measurements at finer temporal resolutions. Furthermore, government bodies have developed certifications to accompany new uses of these sensors, but these certifications have shortcomings. To address these knowledge gaps, PM-LCS of two models, 8 Sensirion SPS30 and 8 Plantower PMS5003, were collocated for one year with a Fidas 200S, MCERTS-certified PM monitor and were characterised at 2 min resolution, enabling replication of certification processes, and highlighting their limitations and improvements. Robust linear models using sensor-reported particle number concentrations and relative humidity, coupled with 2-week biannual calibration campaigns, achieved reference-grade performance, at median PM_2.5 background concentration of 5.5 μg/m³, demonstrating that, with careful calibration, PM-LCS may cost-effectively supplement reference equipment in multi-nodes networks with fine spatiotemporality.

SUBMITTER: Bulot FMJ

PROVIDER: S-EPMC10176080 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Characterisation and calibration of low-cost PM sensors at high temporal resolution to reference-grade performance.

Bulot Florentin M J FMJ Ossont Steven J SJ Morris Andrew K R AKR Basford Philip J PJ Easton Natasha H C NHC Mitchell Hazel L HL Foster Gavin L GL Cox Simon J SJ Loxham Matthew M

Heliyon 20230429 5

Particulate Matter (PM) low-cost sensors (LCS) present a cost-effective opportunity to improve the spatiotemporal resolution of airborne PM data. Previous studies focused on PM-LCS-reported hourly data and identified, without fully addressing, their limitations. However, PM-LCS provide measurements at finer temporal resolutions. Furthermore, government bodies have developed certifications to accompany new uses of these sensors, but these certifications have shortcomings. To address these knowled ...[more]

PMID: 37187904

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Dataset Information

Characterisation and calibration of low-cost PM sensors at high temporal resolution to reference-grade performance.

Publications

Characterisation and calibration of low-cost PM sensors at high temporal resolution to reference-grade performance.

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