Comparison of Integrated Filter and Automated Carbon Aerosol Measurements at Research Triangle Park, North Carolina

Figures & data

TABLE 1 Summary of comparisons between automated and filter-based measurements

Study location	Y	X	Slope (se ^a )	Intercept (se ^a )	r	Mean y/x ratio	N	Reference
Glendora, CA August 1986	EC TOA	BC Aeth.	1.05 ± 0.14 μg m^−3	−0.09 ± 0.45 μg m^−3	0.89	NR ^b	17	Hansen and McMurry (1990)
Mainz, Germany 28 Mar.–2 Oct. 1994	BC Aeth.	EC TOA	0.39 ± 0.02 μg C m^−3	0 ± 0.29 μg C m^−3	0.85	NR	36	Kulbusch et al. (1998)
Uniontown, PA Summer 1992	BC Aeth.	EC TOR	0.95 ± 0.04 μg m^−3	−0.2 ± 0.4 μg m^−3	0.96	0.86	63	Allen et al. (1999)
Antwerp, Belgium Oct.–Nov. 1995	BC Aeth.	5400 EC	1.2 μg m^−3	0.17 μg m^−3	0.89	NR	NR	Berghmans et al. (1996)
Bakersfield, CA 8–29 Jan. 1999	BC Aeth.	EC TOR	0.63 ± 0.06 μg m^−3	0.17 ± 0.10 μg m^−3	0.87	0.75	36	Babich et al. (2000)
Chicago, IL 10 Oct.–15 Nov. 1997	BC Aeth.	EC TOR	0.76 ± 0.03 μg m^−3	0.05 ± 0.05 μg m^−3	0.98	0.79	35	Babich et al. (2000)
Dallas, TX 5 Dec.–20 Jan. 1998	BC Aeth.	EC TOR	0.62 ± 0.04 μg m^−3	−0.01 ± 0.06 μg m^−3	0.95	0.62	34	Babich et al. (2000)
Philadelphia, PA 1 Aug.–1 Sept. 1998	BC Aeth.	EC TOR	0.62 ± 0.05 μg m^−3	0.12± 0.09 μg m^−3	0.95	0.70	18	Babich et al. (2000)
Phoenix, AZ 10 Dec.–25 Jan. 1998	BC Aeth.	EC TOR	0.71 ± 0.04 μg m^−3	0.36 ± 0.15 μg m^−3	0.96	0.80	33	Babich et al. (2000)
Riverside, CA 15 Aug.–20 Sept. 1997	BC Aeth.	EC TOR	0.83 ± 0.07 μg m^−3	−0.03 ± 0.13 μg m^−3	0.92	0.81	31	Babich et al. (2000)
Atlanta, GA Aug.–1 Sept. 1999	BC Aeth.	In situ TOT EC	1.23 μg C m^−3	−0.30 μg C m^−3	0.95	1.12	269	Lim et al. (2003)
Aug.–1 Sept. 1999	BC Aeth.	5400 EC	1.24 μg C m^−3	−0.87 μg C m^−3	0.90	0.93	542	Lim et al. (2003)
Aug.–1 Sept. 1999	In situ TOT TC	5400 TC	0.96 μg C m^−3	1.19 μg C m^−3	0.91	1.02	197	Lim et al. (2003)
Aug.–1 Sept. 1999	5400 OC	In situ TOT OC	0.99 μg C m^−3	1.15 μg C m^−3	0.85	0.92	197	Lim et al. (2003)
Aug.–1 Sept. 1999	5400 EC	In situ TOT EC	0.96 μg C m^−3	0.57 μg C m^−3	0.86	1.20	197	Lim et al. (2003)
Fresno, CA 1 Jan.–26 Dec. 2000	5400 TC	RAAS TC TOR	0.31 ± 0.02 μg m^−3	6.22 ± 0.17 μg m^−3	0.42	1.48	36	Watson and Chow (2002)
1 Jan.–26 Dec. 2000	5400 OC	RAAS OC TOR	0.20 ± 0.02 μg m^−3	5.42 ± 0.11 μg m^−3	0.31	1.48	36	Watson and Chow (2002)
1 Jan.–26 Dec. 2000	5400 EC	RAAS EC TOR	1.10 ± 0.09 μg m^−3	1.75 ± 0.28μg m^−3	0.74	1.53	34	Watson and Chow (2002)
1 Jan.–26 Dec. 2000	5400 EC	BC Aeth.	1.05± 0.05 μg m^−3	0.28 ± 0.05 μg m^−3	0.71	1.63	37	Watson and Chow (2002)
1 Jan.–26 Dec. 2000	BC Aeth.	RAAS EC TOR	0.81 ± 0.03 μg m^−3	0.13 ± 0.04 μg m^−3	0.98	0.92	51	Watson and Chow (2002)

TABLE 2 Deming ^a regression and Pearson correlation (r) results

	Sampler		Regression
Parameter	y	x	Slope (± se ^b	Intercept (± se ^b	r	Mean y/x ratio	Number of pairs
TC	5400	RAAS	0.38 (± 0.09)	−0.26 (± 0.64)	0.64	0.36	26
OC	5400	RAAS	0.22 (± 0.05)	−0.03 (± 0.33)	0.67	0.22	26
EC	5400	RAAS	0.95 (± 0.51)	0.43 (± 0.30)	0.37	1.89	24
EC	AETH	RAAS	1.17 (± 0.16)	0.06 (± 0.10)	0.86	1.30	21
EC	5400	AETH	0.94 (± 0.06)	0.29 (± 0.05)	0.55	1.39	558
EC	5400	AETH2.5	0.79 (± 0.02)	0.25 (± 0.02)	0.92	1.17	189

TABLE 3 Minimum (Min.), maximum (Max.), mean (μ), and median (Med.) concentrations by comparison and method

		OC, μg C m^−3				EC or BC, μg C m^−3				TC, μg C m^−3
y to x comparison	Method	Min.	Max.	μ	Med.	Min.	Max.	μ	Med.	Min.	Max.	μ	Med.
5400 to RAAS	5400	0.63	2.52	1.36	1.24	0.35	1.57	0.89	0.83	0.98	4.09	2.26	2.07
5400 to RAAS	RAAS	2.91	11.4	6.14	5.58	0.14	1.64	0.47	0.44	2.98	11.7	6.56	6.10
AETH to RAAS	AETH	—	—	—	—	0.29	1.95	0.65	0.56	—	—	—	—
AETH to RAAS	RAAS	—	—	—	—	0.14	1.64	0.50	0.46	—	—	—	—
5400 to AETH	5400	—	—	—	—	0.13	4.20	0.92	0.83	—	—	—	—
5400 to AETH	AETH	—	—	—	—	0.07	3.55	0.66	0.53	—	—	—	—
5400 to AETH2.5	5400	—	—	—	—	0.12	2.71	0.77	0.62	—	—	—	—
5400 to AETH2.5	AETH2.5	—	—	—	—	0.08	3.04	0.66	0.36	—	—	—	—

FIG. 1 Comparison of the R&P 5400 TC to the RAAS TOT TC concentrations (μg C m⁻³) measured 1 July to 2 October 2002. The solid line represents the Deming linear regression, and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 2 Comparison of the R&P 5400 OC and RAAS TOT OC concentrations (μg C m⁻³) measured 1 July to 2 October 2002. The solid line represents the Deming linear regression and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 3 Comparison of the R&P 5400 EC and RAAS TOT EC OC concentrations (μg C m⁻³) measured 1 July to 2 October 2002. The solid line represents the Deming linear regression and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 4 Difference in RAAS TOT and R&P 5400 measurements as a function of RAAS TOT concentration (μg C m⁻³) for (a) OC and (b) EC. The sampling period was 1 July through 2 October 2002. The number of samples for was (a) 26 and (b) 24.

FIG. 5 Comparison of Aethalometer BC and Andersen RAAS filter EC concentrations (μg C m⁻³) measured 1 July to 2 October 2002. The solid line represents the Deming linear regression and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 6 Comparison of R&P 5400 EC and Aethalometer BC, without PM_2.5 inlet (AETH BC) concentrations (μg C m⁻³) measured 1 July to 2 October 2002. The solid line represents the Deming linear regression and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 7 Comparison of R&P 5400 EC and Aethalometer BC with PM_2.5 inlet (AETH2.5) concentrations (μg C m⁻³) measured 23 November to 31 December 2002. The solid line represents the Deming linear regression and the dashed line represents the 1:1 line. The correlation (r), number of samples (N), and mean ratio are also shown.

FIG. 8 Difference in Aethalometer BC and 5400 EC as a function of Aethalometer BC concentration for (a) Aethalometer with the PM_2.5 inlet and (b) Aethalometer without the PM_2.5 inlet. The sampling period was 1 July through 2 October 2002, and the number of samples was (a) 558 and (b) 189. The sampling period was 23 November through 31 December 2002.

Hansen , A. D. A. and McMurry , P. H. 1990 . An Intercomparison of Measurements of Aerosol Elemental Carbon During the 1986 Carbonaceous Species Method Comparison Study . J. Air Waste Manage. Assoc. , 40 ( 6 ) : 894 – 895 .

 Web of Science ®Google Scholar

Allen , G. A. , Lawrence , J. and Koutrakis , P. 1999 . Field Validation of a Semi-Continuous Method for Aerosol Black Carbon (Aethalometer) and Temporal Patterns of Summertime Hourly Black Carbon Measurements in Southwestern PA . Atmos. Environ. , 33 : 817 – 823 .

 Web of Science ®Google Scholar

Berghmans , P. , Pauwels , J. , Roekens , E. and Bogaert , R. 1996 . Comparison of Methods for the Concentrations Measurement of Black (Carbonaceaous) Aerosol in Ambient Air, . J. Aerosol Sci. , 27 ( Suppl. 1 ) : S689 – S690 .

 Google Scholar

Babich , P. , Davey , M. , Allen , G. and Koutrakis , P. 2000 . Method Comparisons for Particulate Nitrate, Elemental Carbon, and PM2.5 Mass in Seven U.S. Cities . J. Air Waste Manage. Assoc. , 50 : 1095 – 1105 .

 Web of Science ®Google Scholar

Lim , H.-J. , Turpin , B. J. , Edgerton , E. , Hering , S. V. , Allen , G. , Maring , H. and Solomon , P. 2003 . Semicontinuous Aerosol Carbon Measurements: Comparison of Atlanta Supersite Measurements, . J. Geophys. Res. , 108 ( D7 ) : 7/1 – 11 .

 Web of Science ®Google Scholar

Watson , J. G. and Chow , J. C. 2002 . Comparison and Evaluation of In Situ and Filter Carbon Measurements at the Fresno Supersite, . J. Geophys. Res. , 107 ( D21 ) : 3/1 – 15 .

 Web of Science ®Google Scholar