Expert: John Locke - 7/3/2011

Question
I have for a long time been a food service worker and seen many a sign about proper handwashing for employees. I was shocked to read that one must wash their hands for 30 seconds. So I timed myself and others and learned the average person washes their hands for only 7 to 10 seconds. So now i count to 30 when washing hands but this truly is a long time and now I worry that I must also do the same in the shower, particularly after noticing how many times i must wash my bum before it stops smelling like poop. So i carefully wash each body part for 30 seconds. This makes for a painfully long shower and people get frustrated, myself included how long it takes me to do these things.
Is this necessary? What is the reason for 30 seconds?  Is it the rubbing action, the soap, or the water that gets you clean. I have eczema and once had a dr. Say not to use soap, only on the genitals and smelly parts. Is that unsanitary? Is water alone enough to get you clean? Does water alone kill bacteria, specifically poop bacteria? I have heard of some people simply rinsing their shoes off with water after stepping in poop, is that truly enough?
What is the rule for proper hygiene? I would really like to stop having to take hour long showers. If it is enough to just be under the water for 30 seconds I would much rather do that?
Thanx for your help with this matter.
M.

Answer
Thanks for using AllExperts. You ask multiple questions relating to proper hand hygiene and cleaning; I will try to answer them to the best of my ability, but the exact answers to all of your questions are not known. Nonetheless, here is what we do know:

Proper hand hygiene does require washing the hands for approximately 30 seconds with soap and water. Using water alone really doesn't do much in terms of eliminating harmful microorganisms or dirt; soap is required to kill and carry away microorganisms from the skin surface. Water will remove some dirt and loosely-adhered microorganisms on the skin surface; adding soap and vigorous scrubbing will loosen more tightly-adhered bacteria, viruses, and fungi and wash them away. Soap does this by surrounding dirt with a matrix of hydrophobic molecules that do not allow it to adhere to whatever surface it is on. Scrubbing helps distribute the soap and loosen large patches of dirt. Some soaps contain a specific antibacterial agent meant to directly kill pathogens on the skin; this can be helpful, but it is not necessary to get the benefit of washing with soap.

Regarding your mention of washing different parts of the body for 30 seconds each: this is unnecessary. The emphasis is placed on good hand hygiene for a very specific reason: people's hands interact with essentially all the things we use on a daily basis, including food. The hands can become contaminated with fecal matter from use of the bathroom (or with harmful microorganisms from other surfaces in the general environment) and then transfer those to food or other people. The hands are most likely to do this in the course of day-to-day activities, hence the emphasis on hand washing (and not, say, careful foot washing). Good hygiene for the rest of the body would simply include normal washing with soap and water on a regular basis.

It is also worth mentioning that the ultimate goal of hand washing is not to completely remove harmful microorganisms from the skin. That is probably impossible, given the shear number that naturally live on our skin. Good hand washing will decrease their numbers by a factor of 100-1000.

Please note that if you are becoming disabled or unable to fulfill the activities of daily life because of the long showers that you are taking, you may wish to consult a physician as to how this habit is negatively affecting your life.

If you wish to read a comprehensive treatment of the subject, you can review the CDC guidelines for hand washing in health care settings. Much of what is included here is applicable to general hand hygiene:

http://www.cdc.gov/mmwr/PDF/rr/rr5116.pdf