A study on hand washing found that most Americans wash their hands, but not long enough.

Most people wash for only 5 seconds.

The fourth annual Healthy Hand Washing Survey found that 70 percent of adults said they always wash their hands after using a public restroom. 29 percent sometimes skip washing their hands and 1 percent admitted they never wash after using a public restroom.

57 percent said they wash their hands for just 5 to 15 seconds.

Seventy-percent said they frequently or occasionally see people leave without washing their hands. 34 percent of men frequently saw non-hand washers, compared to 26 percent of women.

Sixty-two admitted they have just rinsed their hands with water after using a public restroom.

The Centers for Disease Control and Prevention recommends washing hands for at least 20 seconds.

They also suggest singing "Happy Birthday" twice to allow enough time to remove and rinse off germs.