Comment on egusphere-2024-1004 [Labzovskii et al.] DOI Creative Commons
Kristen Okorn, Laura T. Iraci

Published: April 10, 2024

Abstract. We reviewed 60 sensor networks and 15 related efforts (sensor review papers data accessibility projects) to better understand the landscape of stationary low-cost gas-phase deployed in outdoor environments worldwide. This study is not exhaustive every network on globe, but rather exists categorize types by their key characteristics explore general trends. also exposes gaps monitoring date, especially regarding availability measurements compared particulate matter (PM), geographic coverage (the global south, rural areas). ground-based that measure air pollutants into two main subsets based deployment type: quasi-permanent (long-term) campaign (short medium-term) commonplace practices, strengths, weaknesses networks. conclude with a summary cross-network unification quality control efforts. work aims help scientists looking build best practices common pathways, aid end users finding datasets meet needs.

Language: Английский

Spatial Variation of PM<sub>2.5</sub> Indoors and Outdoors: Results from 261 Regulatory Monitors Compared to 14,000 Low-Cost Monitors in Three Western States over 4.7 Years DOI Open Access
Lance Wallace, Tongke Zhao

Published: March 27, 2023

Spatial variation of indoor and outdoor PM2.5 within three states for a 5-year period is studied using regulatory low-cost PurpleAir monitors. Most these data were collected in an earlier study1 investigating the relative contribution indoor-generated outdoor-infiltrated particles to exposures. About 260 monitors ~10,000 ~4,000 are included. Daily mean concentrations, correlations, coefficients divergence (COD) calculated pairs at distances ranging from 0 (collocated) 200 km. We use transparent reproducible open algorithm that avoids proprietary algorithms provided by manufacturer sensors PA-I PA-II The available on API website under name “PM2.5_alt”. This validated several hundred separated up 0.5 spatial outdoors homogeneous with high correlations least 10 km, as shown COD index 0.2. There also steady improvement concentrations increasing distance indoors not even &lt;100 m. document substantial differences between Federal Reference Methods (FRM) Equivalent (FEM).

Language: Английский

Citations

3

Long-Term Indoor-Outdoor PM2.5 Measurements Using PurpleAir Sensors: An Improved Method of Calculating Indoor-Generated and Outdoor-Infiltrated Contributions to Potential Indoor Exposure DOI Creative Commons
Lance Wallace,

Wayne R. Ott

Sensors, Journal Year: 2023, Volume and Issue: 23(3), P. 1160 - 1160

Published: Jan. 19, 2023

Low-cost monitors make it possible now for the first time to collect long-term (months years) measurements of potential indoor exposure fine particles. Indoor is due two sources: particles infiltrating from outdoors and those generated by activities. Calculating relative contribution each source requires identifying an infiltration factor. We develop a method periods when factor not constant searching relatively constant. From initial regression on outdoor particle concentrations, Forbidden Zone can be defined with upper boundary below which no observations should appear. If many appear in Zone, they falsify assumption single This useful quality assurance feature, since investigators may then search subsets data few Zone. The usefulness this approach illustrated using examples drawn PurpleAir network optical monitors. An improved algorithm applied reduced bias, precision, lower limit detection than either proprietary algorithms offered manufacturer sensors used

Language: Английский

Citations

2

Laboratory Comparison of Low-Cost Particulate Matter Sensors to Measure Transient Events of Pollution—Part B—Particle Number Concentrations DOI Creative Commons
Florentin M. J. Bulot, Hugo S. Russell, Mohsen Rezaei

et al.

Sensors, Journal Year: 2023, Volume and Issue: 23(17), P. 7657 - 7657

Published: Sept. 4, 2023

Low-cost Particulate Matter (PM) sensors offer an excellent opportunity to improve our knowledge about this type of pollution. Their size and cost, which support multi-node network deployment, along with their temporal resolution, enable them report fine spatio-temporal resolution for a given area. These have known issues across performance metrics. Generally, the literature focuses on PM mass concentration reported by these sensors, but some models also Particle Number Concentrations (PNCs) segregated into different ranges. In study, eight units each Alphasense OPC-R1, Plantower PMS5003 Sensirion SPS30 been exposed, under controlled conditions, short-lived peaks generated using two combustion sources PM, exposing sensors' particle distributions quantify better understand low-cost range relevant environmental The PNCs were analysed characterise sensor-reported distribution, determine whether can follow transient variations observed reference instruments relative impact variables performances sensors. This study shows that OPC-R1 at least five ranges independently from other, other all not independent other. It demonstrates tested here could track variation PNCs, closely distribution between it composition are more impactful sensor measurements than humidity.

Language: Английский

Citations

2

Reply on CC1 DOI Creative Commons
Kristen Okorn

Published: April 10, 2024

Abstract. We reviewed 60 sensor networks and 15 related efforts (sensor review papers data accessibility projects) to better understand the landscape of stationary low-cost gas-phase deployed in outdoor environments worldwide. This study is not exhaustive every network on globe, but rather exists categorize types by their key characteristics explore general trends. also exposes gaps monitoring date, especially regarding availability measurements compared particulate matter (PM), geographic coverage (the global south, rural areas). ground-based that measure air pollutants into two main subsets based deployment type: quasi-permanent (long-term) campaign (short medium-term) commonplace practices, strengths, weaknesses networks. conclude with a summary cross-network unification quality control efforts. work aims help scientists looking build best practices common pathways, aid end users finding datasets meet needs.

Language: Английский

Citations

0

Comment on egusphere-2024-1004 [Labzovskii et al.] DOI Creative Commons
Kristen Okorn, Laura T. Iraci

Published: April 10, 2024

Abstract. We reviewed 60 sensor networks and 15 related efforts (sensor review papers data accessibility projects) to better understand the landscape of stationary low-cost gas-phase deployed in outdoor environments worldwide. This study is not exhaustive every network on globe, but rather exists categorize types by their key characteristics explore general trends. also exposes gaps monitoring date, especially regarding availability measurements compared particulate matter (PM), geographic coverage (the global south, rural areas). ground-based that measure air pollutants into two main subsets based deployment type: quasi-permanent (long-term) campaign (short medium-term) commonplace practices, strengths, weaknesses networks. conclude with a summary cross-network unification quality control efforts. work aims help scientists looking build best practices common pathways, aid end users finding datasets meet needs.

Language: Английский

Citations

0