Reference Study Location Sample Dates Season No. of Samples Available Data (Statistics) Collection Device Collection Period An alytical Methoda Studies included in the compiled summary of statistics (15 studies) Weisel (2006) NJ 2004– 2005 Varies 100 Population Stats (25/50/75/90/95/Max) Summa canister 24 hours EPA TO-15 NYSDOH (2006) NY 1997– 2003 All 400 Population Stats (25/50/75/90/95/Max) Summa canister 2 hours EPA TO-15 Rago et al. (2004, 2005) MA 2004– 2005 Spring, Fall 100 Population Stats (25/50/75/90/Max) Summa canister 24 hours EPA TO-15 Zhu et al. (2005) Ottawa, CA 2002– 2003 Winter 75 Population Stats (50/75/90/Max) Sorbent tube, active sampler 1.7 hours GC/MS Sexton et al. (2004) Minneapolis, MN 1999 Spring, Summer, Fall 292 Population Stats (50/90) Charcoal passive sampler 48 hours GC/MS Foster et al. (2002) Denver, CO 1998– 2001 All— Quarterly 427 Population Stats (25/50/75/90/95/Max) Summa canister 24 hours EPA TO 14/15 SIM Kurtz and Folkes (2005) Denver, CO 1998– 2001 All— Quarterly 282 Population Stats (50/90/95/Max) Summa canister 24 hours EPA TO 14/15 SIM Van Winkle and Scheff (2001) Chicago, IL 1994– 1995 All 48 Population Stats (50/90/Max) Summa canister 24 hours EPA TO-14 Clayton et al. (1999) Midwest States 1995– 1997 All 395 Actual Data (25/50/75/90/95/Max) Passive sorbent sampler 6 days GC/MS Gordon et al. (1999) AZ 1995– 1997 All 185 Population Stats (50/75/90/Max) Passive sorbent sampler 6 days GC/MS Mukerjee et al. (1997) Brownsville, TX 1993 Spring 9 Population Stats (50) Multi-sorbent active canister 24 hours GC/MS Heavner et al. (1996) Mt. Laurel, NJ 1992 Winter 61 Population Stats (50/Max) Active multi-sorbent sampler 14 hours GC/MS Heavner et al. (1995) Columbus, OH 1991 Winter 24 Population Stats (50/Max) Multi-sorbent sampler w/pump 3 hours GC/MS Sheldon et al. (1992) Woodland, CA 1990 Summer 125 Population Stats (25/50/75/90/Max) Canister and active sorbent sampler 24 hours GC/MS Pre-1990 Studies evaluated but not included in the compiled summary of statistics (3 studies) U.S.-EPA (1987a) Los Angeles, CA (1) 1984 Winter, Summer 111 Population Stats (25/50/75/90/95/Max) Tenax 12 hours GC/FID Contra Costa, CA (2) 1984 Summer 68 Population Stats (25/50/75/90/95/Max) Tenax 12 hours GC/FID U.S.-EPA (1987b) Elizabeth and Bayonne, NJ 1981 Fall 348 Population Stats (25/50/75/90/95/Max) Tenax 12 hours GC/FID

aGC/FID = gas chromatography/flame ionization detection; GC/MS = gas chromatography/mass spectrometry; SIM = selected ion monitoring.

Table 6: Summary of Background Indoor Air Quality Studies (1981–2005) selected for Evaluation (adopted and modified from U.S.-EPA report no 530-R-10-001, 2011 [34]).