How Does Hand Washing Kill Germs?

By Susan Revermann
Rolf Otzipka/Photodisc/Getty Images

Hand washing not only keeps your child's hands clean and looking nice; it also cuts down on his chances of picking up and spreading illnesses to every other person he comes across, himself included. Although most parents know they should tell their kids to wash their hands to get rid of germs, most may not know what’s really going on under those suds. The kind of soap used and then hand-washing technique help determine the effects these have on removing germs.

Picking Up Germs

Throughout the day, a child picks up germs from all the random surfaces that he touches, including his own body. Reminding him to wash his hands throughout the day helps keep the germs on his hands in check. It is especially important for your child to wash hands before eating, before and after being around someone who is sick, before and after touching a wound, and after sneezing, coughing, wiping a nose, using the bathroom, petting an animal and playing with things you wish he wouldn't, like the garbage.

The Importance of Soap

Although rinsing your child's hands with water is better than nothing at all, washing with hand soap is a vital step. Regular hand soap and water doesn’t kill the germs on her hands, but it does effectively remove the germs from the skin. Antibacterial soaps contain special ingredients, such as a chemical called triclosan, to help kill germs. However, Mayo Clinic states that antibacterial soaps are no more effective than proper hand-washing with regular soap and that they are best avoided in this age of superbugs because the usage of antibacterial soap may prompt bacteria to evolve into more resistant bacteria. Additionally, antibacterial soap can trigger allergic reactions. On the other hand, Mayo Clinic says alcohol-based hand sanitizers are an acceptable alternative when soap and water are not available, provided the sanitizer has at least 60 percent alcohol. These kill germs by changing the shape of the life-sustaining proteins in bacteria and viruses, thus making them unable to function, explains Harvard Health.

Water Temperature

You may have heard that you must use warm or even hot water to wash your child's hands to blast those germs away. However, according to a 2005 report in the "Journal of Occupational and Environmental Medicine," the water temperature doesn’t matter as much as the length of time actually spent scrubbing with the soap.

Proper Washing Procedure

Your child won’t get rid of those germs unless he actually washes his hands properly. The CDC recommends the following procedure for effective hand washing: Wet hands with cold or warm water; apply soap; gently scrub all surfaces of the hands, between the fingers and under the fingernails; continue scrubbing for at least 20 seconds or long enough to sing the “Happy Birthday” song twice through; rinse with running water; and dry the hands with clean towel or air dry.