Shuyi Qiu and John S Ji

Many people around the world are still using biomass as a fuel for cooking and heating. Inefficient combustion of solid fuels is the primary cause of indoor household air pollution, estimated to be responsible for 4.3 million premature deaths in 2012 (7.7% of total mortality).

The World Health Organization’s latest global air quality guidelines point out that indoor air pollution causes a health burden that mostly affects people in low- and middle-income countries. Many global development agencies are working with governments of developing countries to reduce household air pollution. For example, China’s Relocation Program in the poorest provinces is a significant part of China’s poverty eradication plans. This large-scale program relocates millions of residents in absolute poverty to places with better living conditions, including fuel type.