Disinfecting vs. Sanitizing

Say you've got a big mess on your hands. You've had some food spill in your kitchen, and you need to decide on a product and method to clean up so you get rid of any potentially hazardous germs. Should you sanitize or disinfect? What's the difference between the two anyway?

You might be surprised to learn that, even though people tend to use the terms interchangeably, there's a legal difference. In the United States, sanitizers are agents that destroy 99.999 percent of bacteria in 30 seconds during the Official Detergent Sanitizer Test (a public health test). A good way to understand the logic behind this test is to think of a bartender washing glasses. He'll have to kill as many germs as possible in a short time to be able to put the glasses away quickly.

On the other hand, disinfectants are products that destroy all organisms (including infectious fungi and bacteria) in 10 minutes during the AOAC Use Dilution Test, a test regulated by the EPA to determine the efficiency of disinfectants. In a hospital situation it's more important to kill all germs even if it takes longer rather than to kill most of them quickly.

Here's how the CDC explains the differences:

Cleaning only removes visible dirt and germs from surfaces. Usually you use soap and water for this. You're not necessarily killing germs but by removing them physically, you're lowering their number and your risk of infection.

Disinfecting uses chemicals to destroy germs not visible to the naked eye rather than simply reducing them. The procedure may not necessarily clean a dirty surface, but by disinfecting it, you reduce the risk of infection. You might disinfect areas where you change a baby's diaper. Hospitals disinfect areas that have come into contact with blood or other body fluids.

Sanitizing lowers the number of germs to a safe level as judged by public health standards. It can involve either cleaning or disinfecting (or both). Usually you sanitize in kitchens and other areas that come into contact with food. For example, you sanitize dishes and utensils after using them. You may also sanitize toys that children put in their mouths.

If you're trying to get rid of bacteria and viruses (for instance during flu season or a coronavirus outbreak), you'll want to disinfect rather than sanitize. EPA-approved sanitizers only take care of bacteria, while EPA-approved disinfectants kill both bacteria and viruses.

On the next page we'll talk about how to disinfect and sanitize using bleach.