A food worker can wash her hands only in a designated handwashing sink. This sink is specifically designed for handwashing and is equipped with necessary items like soap and a disposable towel or hand-drying device. It is never appropriate to wash hands in sinks used for food preparation, dishwashing, utility tasks, or defrosting meat, as they can contaminate the hands and spread foodborne illnesses. These designated handwashing sinks should be conveniently located in food preparation, serving areas, dishwashing areas, and adjacent to toilets for accessibility and proper hygiene compliance. Maintaining clear access to these sinks and using them only for handwashing is critical to food safety.