Transcript Slide 1

Carbon Meeting
Joann Rice
Sacramento, CA
January 22-23, 2008
“Old” versus “New” CSN Carbon

“Old” CSN
 MetOne SASS sampler
 6.7 LPM flow rate with active flow control
 46.2-mm QMA Quartz filter
 CSN TOT analysis by RTI
 OC in He (900C); EC in He/O2 (920C)

“New” CSN
 URG3000N sampler (IMPROVE-like)
 22 LPM flow rate with active flow control
 25-mm Pallflex Quartz filter
 IMPROVE_A TOR analysis by DRI
 OC in He (580C); EC in He/O2 (840C)

SOPs posted at
http://www.epa.gov/ttn/amtic/specsop.html
“Old” versus “New” CSN Carbon
First Look

Two months (May-June 2007) of collocated old
and new CSN at all Phase 1 sites
 Collocation
was resource restricted
 For purposes of overlap only to minimize data loss
 About 10-20 collocated observations per site


No artifact adjustments made to either old or
new CSN data
No data screening for MDL or other outliers
“Old” versus “New” CSN OC
“Old” versus “New” CSN OC
70
95% CI Notched Outlier Boxplot
60
95% CI Mean Diamond
Outliers > 1.5 and < 3 IQR
50
Outliers > 3 IQR
40
30
20
10
0
88305 OC CSN
TOT
88370 OC TOR
Unadj
n
88305 OC CSN TOT
88370 OC TOR Unadj
Mean
522
520
95% CI
5.01
3.31
4.64 5.37
3.00 3.63
SE
SD
0.19
0.16
4.25
3.68
“Old” versus “New” CSN EC
“Old” versus “New” CSN EC
6
95% CI Notched Outlier Boxplot
95% CI Mean Diamond
5
Outliers > 1.5 and < 3 IQR
4
Outliers > 3 IQR
3
2
1
0
88307 EC CSN
TOT
88380 EC TOR
Unadj OP
n
88307 EC CSN TOT
88380 EC TOR Unadj OP
Mean
521
519
95% CI
0.67
0.81
0.63 0.71
0.76 0.85
SE
SD
0.02
0.02
0.44
0.54
Collocated “Old” CSN OC
Collocated “Old” CSN EC