How long should hands be vigorously rubbed with soap during washing?

The guideline of vigorously rubbing hands with soap for at least 20 seconds is recommended to effectively remove germs and prevent the spread of infections. This duration allows enough time to cover all surfaces of the hands, including between fingers, under nails, and around the wrists, ensuring that soap has sufficient contact time to break down and lift away dirt and pathogens.

Research and health authorities such as the Centers for Disease Control and Prevention suggest this 20-second timeframe to maximize the effectiveness of hand hygiene. Shorter durations, like 10 or 15 seconds, may not be sufficient for thorough cleaning, potentially leaving behind harmful microorganisms that could lead to illness. On the other hand, while 30 seconds is more than adequate, it is not necessary for most situations, as 20 seconds is generally established as the optimal time for effective handwashing.