Table 2.

Geometric means of PM_2.5 concentrations between pre- and postintervention for each household.

HH	Total			Bedroom			Kitchen			Living room
	Pre	Post	Difference	Pre	Post	Difference	Pre	Post	Difference	Pre	Post	Difference
1	7.91	10.48	2.57	8.61	9.63	1.03	9.61	11.28	1.67	5.51	10.53	5.02
2	19.49	18.38	−1.11∗	15.36	17.17	1.81	20.11	15.00	−5.11∗	23.00	22.98	−0.02
3	11.08	10.74	−0.34	12.35	12.26	−0.09	13.23	12.35	−0.88∗	7367	7.62	−0.05
4	19.46	13.27	−6.19∗	13.76	11.59	−2.17∗	21.99	15.67	−6.32∗	22.62	12.56	−10.06∗
5	16.39	15.96	−0.43	20.28	17.44	−2.84∗	15.20	17.69	2.49	13.69	12.76	−0.93∗
6	15.50	12.81	−2.69∗	11.00	9.37	−1.63∗	19.22	16.62	−2.60∗	16.27	12.45	−3.82∗
7	14.41	13.50	−0.91	18.00	13.28	−4.72∗	6.34	7.91	1.57	18.89	19.30	0.41
8	15.19	12.16	−3.03∗	17.08	13.59	−3.49∗	16.73	14.22	−2.51∗	11.77	8.68	−3.09∗
9	11.58	9.75	−1.83	10.72	7.54	−3.18∗	12.10	11.47	−0.63∗	11.93	10.25	−1.68∗
10	11.25	12.73	1.48	8.90	9.58	0.68	13.96	15.82	1.86	10.89	12.78	1.89
11	19.82	18.34	−1.48∗	18.21	18.58	0.37	22.34	18.84	−3.50∗	18.91	17.59	−1.32∗
12	22.07	16.67	−5.40∗	23.08	16.25	−6.83∗	24.50	20.90	−3.60∗	18.62	12.87	−5.75∗
13	20.05	23.52	−5.53∗	35.39	28.81	−6.58∗	23.41	16.66	−6.75∗	28.34	25.10	−3.24∗
Total	16.40	14.48	−1.91∗	16.36	14.24	−2.13∗	16.83	14.96	−1.87∗	16.01	14.27	−1.74∗

Note. The two-sample t-test and Wilcoxon signed-rank test were used to test the improvement within each household and over 13 households between pre- and postintervention, respectively. ^∗Significant at p < 0.05