Feasibility study on the detection of airborne particulates in a dental surgery using an optical particle counter

Abstract. Inter-comparison of results from two kinds of aerosol systems in the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) passenger aircraft based observatory, operating during intercontinental flights at 9–12 km altitude, is presented. Aerosol from the lowermost stratosphere (LMS), the extra-tropical upper troposphere (UT) and the tropical mid troposphere (MT) were investigated. Aerosol particle volume concentration measured with an optical particle counter (OPC) is compared with analytical results of the sum of masses of all major and several minor constituents from aerosol samples collected with an impactor. Analyses were undertaken with accelerator-based methods particle-induced X-ray emission (PIXE) and particle elastic scattering analysis (PESA). Data from 48 flights during one year are used, leading to a total of 106 individual comparisons. The ratios of the particle volume from the OPC and the total mass from the analyses were in 84% within a relatively narrow interval. Data points outside this interval are connected with inlet-related effects in clouds, large variability in aerosol composition, particle size distribution effects and some cases of non-ideal sampling. Overall, the comparison of these two CARIBIC measurements based on vastly different methods show good agreement, implying that the chemical and size information can be combined in studies of the MT/UT/LMS aerosol.

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Facility for calibration of optical and condensation particle counters based on a turbulent aerosol mixing tube and a reference optical particle counter

Review of Scientific Instruments ◽

10.1063/1.5095853 ◽

2019 ◽

Vol 90 (7) ◽

pp. 075111 ◽

Cited By ~ 3

Author(s):

Stefan Horender ◽

Kevin Auderset ◽

Konstantina Vasilatou

Keyword(s):

Particle Counter ◽

Optical Particle Counter

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14.P.16 Size analysis of airborne bacteria by an optical particle counter and an impactor

Journal of Aerosol Science ◽

10.1016/0021-8502(94)90301-8 ◽

1994 ◽

Vol 25 ◽

pp. 141-142 ◽

Cited By ~ 1

Author(s):

R. Maus ◽

F. Löffler

Keyword(s):

Size Analysis ◽

Airborne Bacteria ◽

Particle Counter ◽

Optical Particle Counter ◽

P 16

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Evaluation of a low-cost optical particle counter (Alphasense OPC-N2) for ambient air monitoring

Atmospheric Measurement Techniques ◽

10.5194/amt-11-709-2018 ◽

2018 ◽

Vol 11 (2) ◽

pp. 709-720 ◽

Cited By ~ 90

Author(s):

Leigh R. Crilley ◽

Marvin Shaw ◽

Ryan Pound ◽

Louisa J. Kramer ◽

Robin Price ◽

...

Keyword(s):

Low Cost ◽

Ambient Air ◽

Particle Mass ◽

Particle Counter ◽

Optical Particle Counter ◽

Attractive Option ◽

Kohler Theory ◽

Pm2.5 And Pm10 ◽

The Uk ◽

Mass Concentrations

Abstract. A fast-growing area of research is the development of low-cost sensors for measuring air pollutants. The affordability and size of low-cost particle sensors makes them an attractive option for use in experiments requiring a number of instruments such as high-density spatial mapping. However, for these low-cost sensors to be useful for these types of studies their accuracy and precision need to be quantified. We evaluated the Alphasense OPC-N2, a promising low-cost miniature optical particle counter, for monitoring ambient airborne particles at typical urban background sites in the UK. The precision of the OPC-N2 was assessed by co-locating 14 instruments at a site to investigate the variation in measured concentrations. Comparison to two different reference optical particle counters as well as a TEOM-FDMS enabled the accuracy of the OPC-N2 to be evaluated. Comparison of the OPC-N2 to the reference optical instruments shows some limitations for measuring mass concentrations of PM1, PM2.5 and PM10. The OPC-N2 demonstrated a significant positive artefact in measured particle mass during times of high ambient RH (> 85 %) and a calibration factor was developed based upon κ-Köhler theory, using average bulk particle aerosol hygroscopicity. Application of this RH correction factor resulted in the OPC-N2 measurements being within 33 % of the TEOM-FDMS, comparable to the agreement between a reference optical particle counter and the TEOM-FDMS (20 %). Inter-unit precision for the 14 OPC-N2 sensors of 22 ± 13 % for PM10 mass concentrations was observed. Overall, the OPC-N2 was found to accurately measure ambient airborne particle mass concentration provided they are (i) correctly calibrated and (ii) corrected for ambient RH. The level of precision demonstrated between multiple OPC-N2s suggests that they would be suitable devices for applications where the spatial variability in particle concentration was to be determined.

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