In which of the following circumstances should alcohol-based hand rubs be avoided?

Alcohol-based hand rubs should be avoided when hands are contaminated with visible soil because these products are most effective when used on clean hands that are not visibly dirty or soiled. When dirt, debris, or fluids are present, the alcohol may not be able to penetrate and effectively kill pathogens. In such cases, washing hands with soap and water is the preferred method to ensure proper hygiene. Dry hands, performing skin tests, and before eating food generally do not preclude the use of alcohol-based hand rubs as long as the hands are not visibly soiled or contaminated.