Table 2.

Descriptive statistics and variance components of outdoor VOC concentrations. Otherwise as Table 1.

VOCs	DF (%)	Descriptive statistics (n = 144)				Variance Components (n = 437)
		Mean (μg m−3)	SD (μg m−3)	Median (μg m−3)	Max (μg m−3)	${\sigma }_{\mathrm{C}}^2$ (%)	${\sigma }_{\mathrm{R}}^2$ (%)	${\sigma }_{\mathrm{S}}^2$ (%)	${\sigma }_{\mathrm{E}}^2$ (%)
Aromatic compounds
Benzene	100	1.2	1.3	1.0	15.2	10.9	0.0	82.2	6.9
Toluene	100	3.3	9.6	1.8	114.2	37.6	0.0	56.0	6.4
Ethylbenzene	100	0.7	2.7	0.3	31.9	38.3	0.0	55.3	6.4
p,m-Xylene	100	3.0	13.5	1.3	162.4	41.5	1.0	51.6	5.9
o-Xylene	100	0.9	3.9	0.4	47.3	41.3	0.0	49.9	8.8
Styrene	92	0.0	0.0	0.0	0.3	19.2	0.0	53.6	27.2
1,2,4-Trimethylbenzene	99	0.9	3.2	0.4	38.0	44.4	0.0	45.8	9.8
1,3,5-Trimethylbenzene	99	0.3	0.9	0.1	10.2	45.1	3.4	37.8	13.7
1,2,3-Trimethylbenzene	99	0.2	0.5	0.1	5.6	45.4	0.0	35.3	19.2
4-Ethyl toluene	98	1.0	3.5	0.5	41.6	35.0	0.6	45.7	18.7
2-Ethyl toluene	99	0.2	0.6	0.1	6.6	42.6	0.0	42.3	15.1
Isopropylbenzene	97	0.0	0.1	0.0	0.9	35.2	0.6	27.4	36.8
n-Propylbenzene	98	0.1	0.5	0.1	5.5	44.1	1.4	31.5	22.9
p-Isopropyltoluene	95	0.0	0.1	0.0	1.0	31.9	0.0	50.5	17.6
Naphthalene	94	0.3	0.6	0.2	6.0	5.6	0.0	49.6	44.9
Chlorinated compounds
Tetrachloroethene	97	0.3	0.3	0.2	2.0	28.8	5.3	6.0	59.9
Carbon tetrachloride	100	1.0	0.3	1.0	2.2	2.9	0.0	58.6	38.5
1,4-Dichlorobenzene	92	0.1	0.2	0.0	1.7	17.4	13.6	14.4	54.6
Aliphatic compounds
Methyl cyclohexane	97	0.2	0.5	0.1	6.4	25.8	0.0	29.2	45.1
n-Nonane	83	0.2	0.4	0.1	3.5	11.4	0.0	45.3	43.3
n-Decane	89	0.2	0.3	0.1	2.9	20.4	1.5	39.8	38.3
Terpenoid compounds
α-Pinene	99	0.2	0.2	0.1	1.5	0.0	0.0	64.5	35.5
d-Limonene	97	0.4	0.9	0.1	8.4	32.8	0.0	11.8	55.4