Commercial janitors are a group of primarily immigrant, low-wage workers who face significant risk at work, and are difficult to reach. Few occupational studies have trained workers to collect research data from peers with electronic data collection tools. In response to a request from a local union representing commercial janitors, University of Washington School of Public Health researchers, led by Dr. Noah Seixas, professor of environmental and occupational health sciences, developed a study in which the janitors themselves collaborated on the study design, recruitment and interviewing process.