Direct exposure to household air pollution (HAP) from polluting fuels results in 2.3 million premature yearly deaths globally. HAP emitted indoors escapes outdoors and is a leading source of outdoor ambient fine particulate air pollution (AAP) in low- and middle-income countries, often being a larger contributor than well-recognized sources. We review published scientific studies that model the contribution of HAP to AAP at global and major sub-regional scales and find that HAP is a dominant source of ambient fine particulate matter (PM2.5) globally.

Household energy surveys typically occur a few times at most during a study. We deployed more frequent surveys — every couple of months in Jharkhand, every week for a couple of months in Bihar — to better understand household preferences and what impacts fuel use choices. Repeat phone surveys — whether weekly or monthly — provide important nuance on the dynamics of household energy use.

Birthweight findings from the HAPIN LPG stove and fuel trial intention-to-treat analyses found an adjusted mean difference of 19.5 g (95% confidence interval, −10.1 to 49.2). Secondary analyses indicate a stronger effect amongst those who received the intervention earlier in pregnancy. Published in the New England Journal of Medicine.