TABLE 2.

CO and PM_2.5 Kitchen-Based Concentrations in Households in 2 Randomized Trials Attributable to Improved Stoves, Adjusted for Potential Confounding, Rural Nepal

	Trial 1		Trial 2
Measures of Exposure	Traditional BiomassN=2963	Vented BiomassN=2752	Vented BiomassN=659	LPGN=661
Total daily PM_2.5, mean (95% CI), μg/m³	1380 (1336, 1425)	936 (895, 978)	885 (810, 959)	442 (405, 482)
Time above 100 μg/m³, mean (95% CI), hours, % sampling time	14.4 (14.2, 14.6), 66	11.7 (11.6, 11.8), 54	10.3 (10.0, 10.7), 47	9.2 (0.8, 9.6), 42
Time above 1000 μg/m³, mean (95% CI), hours, % sampling time	5.3 (5.2, 5.4), 24	3.9 (3.8, 4.0), 18	3.6 (3.3, 3.8), 17	2.3 (2.1, 2.4), 11
	n=2011	n=1848	n=526	n=522
Total daily CO, mean (95% CI), ppm	11.0 (10.6, 11.4)	6.7 (6.4, 7.1)	5.5 (5.0, 6.0)	1.7 (1.5, 1.9)
Time above 6 ppm, mean (95% CI), hours, % sampling time	6.6 (6.4, 6.8), 30	4.3 (4.1, 4.4), 20	3.4 (3.1, 3.6), 16	1.1 (1.0, 1.3), 5
Time above 9 ppm, mean (95% CI), hours, % of sampling time	4.9 (4.7, 5.0), 23	3.2 (3.1, 3.4), 15	2.6 (2.4, 2.9), 12	0.7 (0.6, 0.8), 3

Abbreviations: CI, confidence interval; CO, carbon monoxide; LPG, liquid petroleum gas; PM_2.5, particulate matter of 2.5 μm or less.
a Adjusted for rainfall and temperature on the day of measurement.