Ensuring the safety of fresh fruit is a top priority of fresh produce packinghouses. The aim of this one-year research project is to evaluate and improve sanitizing treatments for sizer carriers in stone fruit packinghouses. The project will not only describe the potential for sizer carriers to harbor pathogens and allow for their growth under different environmental conditions, but will also define a set of sanitizers and application methods that represent the greatest promise for evaluation at the commercial level. Environmental sampling will be performed in active commercial packinghouses to determine natural microbial loads on fruit contact surfaces of sizer carriers. Subsequently, laboratory inoculation studies will be performed to determine the growth potential of foodborne pathogens on fruit sizer carriers under varied humidity and temperature. Furthermore, the potential of clean-in-place (CIP) sanitization will be evaluated by applying no-rinse sanitizers (steam and aerosol antimicrobial chemicals) to the sizer carriers. Results from this study potentially will be applicable to diverse fresh fruit packinghouses for preventing pathogen cross-contamination in produce packing operations. Findings and recommendations will be reported and/or disseminated through industry meetings and technical publications.