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On thresholds for controlling negative particle (PM2.5) readings in air quality reporting
Ningbo Jiang1, Rinat Akter2, Glenn Ross2
1Science, Economics and Insights Division, New South Wales Department of Planning and Environment, Sydney, Australia. Ningbo.Jiang@environment.nsw.gov.au.
Environmental Monitoring and Assessment
|September 12, 2023
Summary
Negative PM2.5 readings can occur due to instrument limitations. A threshold of -10.0 μg/m³ is proposed for controlling these values in air quality data, ensuring accurate reporting.
Area of Science:
- Environmental Science
- Atmospheric Chemistry
- Air Quality Monitoring
Background:
- Ambient PM2.5 monitoring is crucial globally, but instruments can produce erroneous negative readings.
- Negative PM2.5 values are physically impossible and can stem from instrument faults or inherent limitations.
Conclusions:
- The proposed -10.0 μg/m³ threshold effectively manages negative PM2.5 data without significantly impacting key compliance statistics.
- This methodology offers a valuable approach for air quality monitoring in other Australian regions and internationally.
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