Topic Significance & Study Purpose/Background/Rationale C. difficile is the most common organism to cause healthcare-associated infection (HAI) in the United States (Dubberke, Carling, Carrico, Donskey, Loo, McDonald, et al., 2014). C. diff infection (CDI) rates in Hematopoietic Stem Cell Transplant (HSCT) recipients are up to 9-fold higher than those in other inpatient units due to weakened immune systems, long hospitalizations and antibiotic treatments (Bruminhent, Wang, Hu, Wagner, Sunday, Hegarty, et al., 2014). The nursing team and Infection Prevention and Control (IPC) personnel on the HSCT unit noticed the cluster of HAI CDI. From January to June 2019 the unit had a total of 10 cases; 6 cases alone were in May 2019, raising concern about daily practice. Evidence-based strategies have been implemented to reduce environmental contamination and increase education of patients, visitors, and staff. This paper describes how the unit established a “ZERO Harm” comprehensive plan to reduce the number of HAI CDI by 20% in six months on a 16-bed HSCT inpatient unit. Methods, Intervention, & Analysis Established meetings with Environmental Service (EVS) and Food & Nutrition (F&N) and nursing team to discuss action plan. • Implemented double cleaning of room, adenosine triphosphate (ATP) inspection for isolation rooms. • Educated staff regarding sending stool specimens for polymerase chain reaction (PCR) testing. • Utilized disposable food trays, stethoscopes and pillows. • Implemented a “No sharing” rule for mobile equipment such as weight scales. • Validated on proper cleanliness of shared equipment such as glucometers by the fluorescent dye. • Educated clinicians in the proper practice of PPE and hand hygiene. Findings & Interpretation The HSCT unit had 13 cases of HAI CDI in 2017, 25 cases in 2018 and 10 cases from January to June 2019. The intervention started in July 2019 and HAI CDI data will be collected until December 2019 for post-intervention evaluation. Discussion & Implications Environmental cleanliness, proper precautions, and education are vital to reduce CDI. Collaboration between nurses, IPC, EVS, and F&N is essential to stop CDI transmission. Utilizing ATP testing and the fluorescent dye method helps to validate proper cleanliness of the environment. Despite reducing HAI CDI to one case in August 2019, there were opportunities identified related to equipment cleanliness and educational gap. Obtaining disposable curtains and additional weight scales is considered. The future implementation of a “clean protocol” for nursing is next step.