As we muddle through another flu season, keeping things clean remains an effective way to stay healthy. But cleaning alone isn’t always enough when it comes to the microscopic germs that can make us sick—sometimes you have to sanitize and disinfect, as well.
There’s a defined difference between cleaning, sanitizing, and disinfecting, and a right and wrong way to go about them. Here are the highlights, with guidance from the CDC.
First, let's discuss the difference between cleaning, sanitizing, and disinfecting, as defined by the CDC:
Cleaning involves physically removing dirt, debris, and (some) germs from surfaces. This is typically done with soap or other cleaners, water, and a little scrubbing (hence the "physical" part). Cleaning only scrapes away some of the germs that can make you sick, but this is often sufficient to stay healthy in general—the germs left on a dinner plate after you wash it in the sink are usually safe as long as you’re in good health.
Sanitizing greatly reduces the germs on a surface, leaving behind a level that’s considered safe. Most sanitizers kill bacteria, but they aren’t necessarily intended to kill viruses (though they often can kill some).
Disinfecting kills everything—both bacteria and viruses.
An important distinction to remember is that sanitizers and disinfectants don’t clean very well—that is, they will kill most or all of the germs, but might not do a very good job of removing dirt and debris. If you only use hand sanitizer, for example, your hands might be sanitized, but they might also still be dirty.
Since cleaning, sanitizing, and disinfecting are different things, it makes sense that you should treat them as such. Here's when to do each:
Clean everything regularly—every day. In fact, the order of germ-killing operations always starts with cleaning (removing debris and dirt), as you can’t as effectively sanitize or disinfect a dirty surface. Cleaning should always comes first when you want to sanitize or disinfect something.
Sanitize surfaces and objects that touch food or might end up in your mouth after every use when you're concerned about illnesses.
Disinfect surfaces if you’re sick (or someone else in the house is sick), or if you or someone in the home has a compromised immune system.
In other words, you normally don’t need to disinfect every day, but you do need to clean and sanitize specific things every day.
If you want to sanitize or disinfect a surface, you’ll need to use a cleaning product that’s appropriate to the task—but don’t put too much faith in labels. Many sanitizing products will claim they kill 99% or even 99.9% of germs, but this is usually deceptive. What they mean is that they kill 99.9% of certain bacteria and viruses. Even then, they usually don’t give you any information as to the conditions under which those tests were performed under—that is, how thoroughly the surfaces were cleaned or how the product was applied.
That doesn’t mean sanitizers are useless, but it does mean that you shouldn’t assume your home is antiseptic and completely germ-free after you use them. If you want to really kill the most bacteria and viruses as possible, you shouldn’t rely solely on a sanitizing product, even if it has that shiny 99.9% claim.
If you’re disinfecting, make sure you read the label and follow the instructions. Most products require you to leave the disinfectant on the surface for a prolonged period of time (sometimes as long as 20 minutes) to ensure full efficacy. If you just spray and wipe, you’re probably not really disinfecting. If you’re looking at a sanitizer or disinfectant that uses isopropyl alcohol, also make sure it’s a 70% strength mixture (as opposed to a 99% alcohol mixture)—the lower strength, counterintuitively, is the sweet spot for disinfecting.
