Making Sanitation Count: Developing and Testing a Device for Assessing Latrine Use in Low-Income Settings

While efforts are underway to expand latrine coverage to an estimated 2.6 billion people who lack access to improved sanitation there is evidence that actual use of latrines is suboptimal,limiting to potential health and environmental gains from containment of human excreta. we developed a passive latrine use monitor (PLUM) and compared its ability to measure latrine activity with structured observation. each plum consisted of a passive infrared motion detector,microcontroller, data storage card,and batteries mounted in a small plastic housing that was positioned inside the latrine. during a field trial in orissa, india,with similar to 115 households, the number of latrine events measured by the PLUMs was in good agreement with that measured by trained observers during 5 h of structured observation per device per week. A significant finding was that the presence of a human observer was associated with a statisticlly significant increase in the number latrine events, i.e, the user modified their behaviour in response to the observer. another advantage of the PLUM was the ability to measure active continuosly for entire week. A shortcoming of PLUM was the inability to separate latrine events that occured in immediate succession leading to possible undercounting during high-traffic periods. The PLUM is a promising technology that can provide detailed measures of latrine use to improve the understanding of sanitation behaviours and how to modify them and for assessing the intended health, livehood, and environmental benefits of improved sanitation.