Table 3.

2004/2005 and 2005/2006 indoor vs. ambient comparison.

Compound	2004/2005 I/O correlation	2004/2005 Proportion of variance explained (r2) indoor vs. ambient	2004/2005 Correlation significance indoor vs. ambient	2005/2006 I/O correlation	2005/2006 Proportion of variance explained (r2) indoor vs. ambient	2005/2006 Correlation significance indoor vs. ambient
Benzenea	0.37	0.137	P < 0.05	−0.15	0.023	n.s.
Bromoforma	N/A	N/A	N/A	b	b	N/A
Chlorobenzenea	N/A	N/A	N/A	0.04	0.002	n.s.
Chloroforma	N/A	N/A	N/A	0.151	0.022	n.s
Cis-1,3-dichloropropene	N/A	N/A	N/A	b	b	N/A
1,2-dibromo-3-chloropropanea	N/A	N/A	N/A	b	b	N/A
1,4-dichlorobenzenea	N/A	N/A	N/A	b	b	N/A
1,4-dimethylbenzene (p xylene)	0.21	0.044	n.s.	−0.07	0.005	n.s
1,2-dimethylbenzene (o xylene)	0.27	0.073	n.s.	−0.07	0.005	n.s.
1,3-dichloropropenea	N/A	N/A	N/A	b	b	N/A
Ethylbenzenea	0.23	0.053	n.s	−0.10	0.010	n.s.
Isopropylbenzene	0.12	0.014	n.s.	−0.13	0.017	n.s.
Naphthalenea	N/A	N/A	N/A	0.032	0.001	n.s.
n-propylbenzene	0.17	0.029	n.s.	−0.03	0.009	n.s.
Trichloroethylenea	N/A	N/A	N/A	−0.05	0.003	n.s.
1,1,2,2-tetrachloroethanea	N/A	N/A	N/A	0.03	0.009	n.s.
Carbon tetrachloridea	0.49	0.240	P < 0.001	−0.07	0.005	n.s.
Toluenea	0.64	0.409	P < 0.001	−0.15	0.023	n.s.
1,2,4-trichlorobenzenea	N/A	N/A	N/A	−.35	0.123	P < 0.05
1,3,5-trimethylbenzene	0.16	0.026	n.s.	0.19	0.036	n.s.
1,2,4-trimethylbenzene	0.15	0.023	n.s.	0.12	0.014	n.s.

^aNote: Clean Air Act Hazardous Air Pollutant.

^bIndicates no statistical analyses possible because less than 3 nonzero values measured. n.s.: not significant.