1. Challenges with Integrated Measurements of OC and BC (or EC)
J. R. Brook, X. Fan, G. Lu
EMEP Workshop on Particulate Matter Measurement & Modeling
New Orleans, LA April 2004

2. Conclusions
The carbonaceous fraction of PM needs to be measured, but there are challenges associated with:
actually defining sub-fractions of the carbon
the sampling methodology
the laboratory analysis
assuring quality in routine programs
These challenges make it even more difficult for the modeling community to develop approaches for predicting carbonaceous PM and for evaluating model estimates using available data.
In addition to improving time-integrated measurement approaches for OC and EC (or BC), real-time or time-resolved techniques need to be further explored as they may help reduce sampling and analytical problems while also providing better insight into the true atmospheric behavior of PM.

3. Improving the National Monitoring of OC
Figure 2. Schematic of experimental setup
Ambient air or
Aerosol generator
ACF or denuder
Impactor
D50=2.5µm
Pump
APS
CPC
SMPS
Aerosol flow
GRIMM
Particle Counter
by-pass flow
5.0 lpm
1.5 lpm

4. Particle Transmission Through Foam
Penetration curves measured for the 1-layer and 2-layer 80ppi ACF; 1- layer and 2-layer 60ppi ACF, at 16.1 cm/s face velocity. All ACF are ¼ inch in thickness, and 47mm in diameter.
Penetration curves measured for the 1-layer and 2-layer 80ppi ACF; 1- layer and 2-layer 60ppi ACF, at, at 9.2 cm/s face velocity. All ACF are ¼ inch in thickness, and 47mm in diameter.
Penetration curves measured for the 1-layer 80ppi ACF, 1-layer 60ppi ACF, and 2-layer 60ppi foam at a 16.1 cm/s face velocity. All ACF are ¼ inch in thickness, and 47mm in diameter. The particles were from the aerosol generator.