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PM2.5 Definition. PM 2.5 : The mass of particulate matter which is measured after passing through a size-selective inlet with a 50 % efficiency cut-off at 2.5 µm aerodynamic diameter.
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PM2.5 Definition • PM2.5: The mass of particulate matter which is measuredafter passing through a size-selective inlet with a 50 % efficiency cut-off at 2.5 µm aerodynamic diameter. • Current Guidelines definition: PM2.5:- Particles that pass through a size-selective inlet with a 50 % efficiency cut-off at 2.5 µm aerodynamic diameter. • Idealised Definition: (Total) PM2.5: The mass of particulate matter which is measured[at close to ambient temperature]*after passing through a size-selective inlet with a 50 % efficiency cut-off at 2.5 µm aerodynamic diameter. *….cooling increases PM through condensation.. Vehicle Standards fix on a specific temperature (47C). • But: “at close to ambient temperature” • IS: current used for Transport (dilution based technique) & not a problem for Agriculture. • IS NOT: currently used for industry, and small combustion based stack measurement techniques where temperatures at measurement points are high (~ 300C) • Therefore measurements for different sources are not “strictly” comparable • Recommendations: • Transparency in methodologies and reporting. • E.g. Working Definition: high temp = “PM at stack conditions”; ambient temperature = “Total PM” • Support long term harmonisation of “at close to ambient temperature” (Total PM) techniques for all sources.. CEN/ISO WG 21 Standard
The Teachers……. • Stefano Caserini (ARPA IT) • Mike Woodfield (AEAT) • Leon Ntziachristos (LAT) • Penny Dilara (JRC)
PM2.5 Chapter Changes • New/Updated Chapters • Further Chapter Needs