Developing evidence for building sanitation justice: A multi methods approach to understanding public restroom quantity, quality, accessibility, and user experiences.

Access to basic sanitation is a human right and a critical environmental determinant of health. In this paper, we detail the development of three tools to investigate sanitation justice: (1) our public restroom spatial database, (2) our field assessment tool, and (3) survey of restroom access experiences. We document our process to collect these data in a consistent, health equity-driven framework. Together, these tools comprise a suite of methods for the examination of public restrooms from the macro- to the micro-level, and highlight key opportunities to promote health and well-being among restroom-reliant populations (e.g., people experiencing homelessness) by advancing sanitation justice in the built environment. With an illustrative case study, we demonstrate how methods triangulation, using the tools in concert, can provide a comprehensive assessment of basic sanitation access in a given region-San Diego, CA. We also detail how each tool can also be used separately to assess key sanitation justice and health equity questions that may be of interest to researchers, public health practitioners, policymakers, and advocates, including: (1) where do public restrooms exist (mapping)?; (2) how accessible are public restroom facilities, and what health-supportive features do they have (field assessment)?; and (3) what are the experiences of people most reliant on the available public restroom facilities (survey)? The results of our case study demonstrate that these adaptable tools can be used to provide meaningful data on and a holistic picture of public restroom quantity, quality, accessibility, and the experiences of public restroom users in a given region.