To address one of the most severe global challenges affecting human health and the environment, two new voluntary product standards (ISO 30500 and ISO 31800) for nonsewered sanitation systems (NSSS) and fecal sludge treatment units (FSTUs) have been developed and published. While providing stringent voluntary product requirements for the containment and the treatment of human excreta with safe outputs (air, liquids, and solids), ISO 30500 and ISO 31800 make the inextricable connections between environmental emission thresholds, technical innovations, and sustainability aspects of NSSS and FSTUs. The purpose of this feature is to discuss these connections.
Keywords: fecal sludge management; nonsewered sanitation; standards; sustainability.