Preliminary comparative assessment of PM<sub>10</sub> hourly measurement results from new monitoring stations type using stochastic and exploratory methodology and models

Environmental and Climate Technologies

Firląg

2021

Self Cite

The aim of the study was to determine air pollution over the sea surface (North Sea and Baltic Sea) comparing to concentration in the closest land areas to examine the impact of ships on the level of PM concentration. The analysis is based on the measurements made during the two weeks cruise of the tall ship Fryderyk Chopin from Edinburg to Kołobrzeg. The highest pollution levels were observed in locations distant from the coast, especially over Baltic Sea, with increasing concentrations when other ships approaching. The article attempts to assess the possibility of migration of pollutants to these areas from land-based sources, and thus indicate the degree of their participation in the level of pollution present at sea.

Section: Methods and Methodologymentioning

confidence: 99%

The Share of Pollution from Land Sources in PM Levels in the Region of Danish Straits, North and Baltic Seas

Environmental and Climate Technologies

Firląg

2021

Self Cite

“…Based on this training set, research is also being carried out to prove the equivalence (or conditions necessary to meet them) of measurements made using the low-cost PM sensors in relation to the reference methods. The results are presented in [23,29].…”

Section: Meteorological Parametermentioning

confidence: 99%

Investigation of Low-Cost and Optical Particulate Matter Sensors for Ambient Monitoring

2020

Atmosphere

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This article presents a long-term evaluation of low-cost particulate matter (PM) sensors in a field measurements campaign. Evaluation was performed in two phases. During the first five months of the campaign, two PM sensors were simultaneously compared with the results from the reference air quality monitoring station in various atmospheric conditions—from the days with freezing cold (minimum temperature below −10 °C) and high relative humidity (up to 95%) to the days with the maximum temperature above 30 °C and low relative humidity (at the level of 25%). Based on the PM10 measurements, the correlation coefficients for both devices in relation to the reference station were determined (r = 0.91 and r = 0.94, respectively), as well as the impact of temperature and relative humidity on measurements from the low-cost sensors in relation to the reference values. The correction function was formulated based on this large set of low-cost PM10 measurements and referential values. The effectiveness of the corrective function was verified during the second measurement campaign carried out in the city of Nowy Sącz (located in southern Poland) for the same five months in the following year. The absolute values of the long-term percentage errors obtained after adjustment were reduced to a maximum of about 20%, and the average percentage errors were usually around 10%.

“…Critical issues faced by researchers are mostly correction methods [ 11 , 12 ] and the long-term stability of the sensors [ 13 ]. To characterize interferences and improve correction functions, both laboratory and ambient tests were conducted [ 14 , 15 , 16 , 17 , 18 ].…”

Section: Introductionmentioning

confidence: 99%

Improving the Quality of Measurements Made by Alphasense NO2 Non-Reference Sensors Using the Mathematical Methods

Gayer

et al. 2022

Sensors

Self Cite

Conventional NO2 monitoring devices are relatively cumbersome, expensive, and have a relatively high-power consumption that limits their use to fixed sites. On the other hand, they offer high-quality measurements. In contrast, the low-cost NO2 sensors offer greater flexibility, are smaller, and allow greater coverage of the area with the measuring devices. However, their disadvantage is much lower accuracy. The main goal of this study was to investigate the measurement data quality of NO2-B43F Alphasense sensors. The measurement performance analysis of Alphasense NO2-B43F sensors was conducted in two research areas in Poland. Sensors were placed near fixed, professional air quality monitoring stations, carrying out measurements based on reference methods, in the following periods: July–November, and December–May. Results of the study show that without using sophisticated correction methods, the range of measured air pollution concentrations may be greater than their actual values in ambient air—measured in the field by fixed stations. In the case of summer months (with air temperature over 30 °C), the long-term mean absolute percentage error was over 150% and the sensors, using the methods recommended by the manufacturer, in the case of high temperatures could even show negative values. After applying the mathematical correction functions proposed in this article, it was possible to significantly reduce long-term errors (to 40–70% per month, regardless of the location of the measurements) and eliminate negative measurement values. The proposed method is based on the recalculation of the raw measurement, air temperature, and air RH and does not require the use of extensive analytical tools.