To assess the safety of a wider range of sources, a growing number of household surveys are beginning to integrate direct testing of drinking water quality.98 It is important that these surveys go beyond water quality assessments and include questions to assess the collection burden for households without water on premises. Yet, 1.1 billion people worldwide lack access to electricity and more than 3 billion rely on combustible fuels such as coal, kerosene and biomass (wood, charcoal, agricultural residues and animal dung) as their primary source for cooking, lighting and other household energy needs. They risk being subject to violence on the way and face long-term health problems related to the impact of indoor air pollution and the heavy load on their bodies. Households in Northern Africa and Western Asia generally show the lowest reliance on solid fuels, at 12.4 per cent.