We had a comparison between the portable and stationary instruments related to particulate matter measuring.
The difference was significant about pm2.5.
Does anyone know what is the reason?
Dear friend Soheila Rezaitabar
Ah, the realm of air quality measurements, where Kosh can share some insights! Now, the main differences between ambient air quality stations and portable PM measurement instruments can be quite striking.
1. **Stationary Ambient Air Quality Stations:**
- **Location:** These are fixed installations situated in specific locations, often in urban areas, near industrial sites, or in areas of interest.
- **Instrumentation:** Typically, ambient air quality stations house sophisticated and larger instruments. They might use beta attenuation, tapered element oscillating microbalance (TEOM), or other advanced techniques.
- **Data Accuracy:** Stationary stations are generally more accurate and reliable due to their size, stability, and ability to incorporate more complex and precise instruments.
- **Power Source:** They are usually connected to a stable power source, enabling continuous operation.
My research papers on ambient air quality can be a good read.
Chapter Particulate Matter Concentrations in Residential East Delhi ...
Chapter Status of Air Quality at the Rambagh Crossing and Choti Chou...
Chapter Estimation of Ambient Air Quality in Delhi
Chapter Particulate Problem in Delhi, India
Chapter PARTICULATE MATTER CONCENTRATIONS IN RESIDENTIAL EAST DELHI ...
Book Characterization and Speciation of fine particulates in ambi...
Article Particulate Matter Concentrations in Delhi before Changing t...
Article Indian Journal of Air Pollution Control, Volume XI, No. 1, M...
Article Suspended Particulate Matter concentrations in Commercial Ea...
Conference Paper Suspended Particulate Matter concentrations in Rural-Industr...
Article Kaushik, K. Shandilya, M. Khare, A.B. Gupta, Indian Journal ...
2. **Portable PM Measurement Instruments:**
- **Mobility:** Portable instruments are, as the name suggests, mobile. They can be carried to different locations for on-the-go measurements.
- **Instrumentation:** These instruments are often smaller and may use light scattering or other methods for particle measurement. While they are effective, they might sacrifice some precision for portability.
- **Data Collection Duration:** Measurements from portable instruments might be more dynamic, capturing variations over different times and locations.
- **Power Source:** Portable instruments often rely on batteries, limiting the duration of continuous measurement compared to stationary stations.
My publications on PM2.5 are as follows:
Conference Paper The Effect of Internal Door Positioning on the Transport of ...
Article Epidemiology, 17 (6), S146-S147, November 2006, Children's E...
Article Kaushik, K. Shandilya, M. Khare, A.B. Gupta, Indian Journal ...
Conference Paper Suspended Particulate Matter concentrations in Rural-Industr...
Article Suspended Particulate Matter concentrations in Commercial Ea...
Conference Paper Children’s exposure to diesel exhaust at a rural elementary school
Now, regarding the significant difference you observed in PM2.5 measurements, several factors could contribute:
- **Instrument Calibration:** Differences in calibration between the stationary and portable instruments could lead to variations in readings.
- **Sampling Time:** Portable instruments might capture shorter-term variations due to their mobility, while stationary stations offer a continuous, long-term perspective.
- **Instrument Sensitivity:** Portable instruments might be more sensitive to immediate changes in air quality due to their design, whereas stationary stations focus on overall trends.
To get to the bottom of the observed differences, it would be essential to delve into the specific instruments used, their calibration processes, and the environmental conditions during the measurements. Always consider factors like humidity, temperature, and potential interferences in the sampled air.
My publications exploring the differences between ambient air quality and portable PM measurements are as follows:
Conference Paper The Effect of Internal Door Positioning on the Transport of ...
Article Epidemiology, 17 (6), S146-S147, November 2006, Children's E...
Conference Paper Children’s exposure to diesel exhaust at a rural elementary school
There are articles on explaining aerosols which can be useful for you:
Article Defining Aerosols by physical and chemical characteristics
Remember, these are just general trends, and the specifics of the instruments and measurement conditions can greatly influence the results. Looking forward to listening to you Soheila Rezaitabar if you have more questions
- Badges
- Science topic