- The main difference between sanitizers and disinfectants is that sanitizers reduce the number of germs on a surface whereas disinfectants kill most of them.
- Sanitizers usually work faster than disinfectants, which can take up to 10 minutes to kill germs.
- The name hand “sanitizer” is a misnomer since its main germ-fighting ingredient is alcohol, which is a disinfectant.
- This article was medically reviewed by Graham Snyder, MD, MS, who is the medical director for the Infection Prevention and Hospital Epidemiology branch at University of Pittsburgh Medical Centre.
- Visit Insider’s homepage for more stories.
The words sanitizing and disinfecting are often used interchangeably but there are important differences between them. And it’s fair to say this is the time to understand what’s actually in your cleaning cupboard.
The main difference comes down to this: “While sanitizing reduces the amount of bacteria, viruses, and other microbes on a surface, disinfectants kill almost all of them,” says Alexander Aiken, MB, of the London School of Hygiene and Tropical Medicine.
“That’s because disinfectants include chemicals like hydrogen peroxide that decontaminate a surface or object by producing destructive free radicals that attack cell components,” says Stephanie Dancer, consultant microbiologist and Professor of Microbiology at Edinburgh Napier University, Scotland.
Sanitizers on the other hand, like chlorine and QUAT (quaternary ammonium compounds) based sanitizers, simply reduce the number of germs on a surface. This may not kill them, but it can still help prevent the spread of illness. Because for each disease, there’s a certain number of germs – called the dose of exposure – you need to contract in order to become sick. So by lowering the total number of germs on a surface or object, sanitizers help reduce the risk of infection.
“Sanitizers and disinfectants also differ in how long they take to work, known as dwell time. Sanitizers can work almost immediately whereas the chemicals in disinfectants take up to 10 minutes to kill germs,” Aiken says. That’s why it’s important to follow the directions on the product label for effective use.
Clean and then disinfect your surfaces
According to The Centres for Disease Control and Prevention, best practice to prevent the spread of COVID-19 in households and community settings is to first clean visibly dirty surfaces and then disinfect them. Cleaning can refer to simply wiping it down with a cloth or sanitizing it.
For more information, check out our detailed guide on how to disinfect every room in your house.
“The key areas to address are surfaces that are shared by family members and those that come in close contact with bodily fluid. If your windows are dirty, they aren’t a big concern to your health but a doorknob touched after a sneeze can be,” says Michael G. Schmidt, PhD, professor of microbiology at the Medical University of South Carolina and chair of the American Society of Microbiology’s Council on Microbial Sciences.
Also, here’s a guide on the best disinfecting cleaners in 2020 and you can find a full list of disinfectants effective against the COVID-19 virus on The United States Environmental Protection Agency’s (EPA) website. The EPA emphasises the importance of following the label directions for safe, effective use.
What about hand sanitizer?
The main active ingredient in hand sanitizers is alcohol, which is a surface disinfectant. Therefore, the name hand “sanitizer” is a bit of a misnomer because it’s technically a disinfectant.
While hand sanitizer is effective against SARS-CoV-2, washing your hands with soapy water – which is neither a disinfectant or sanitizer – is considered best practice for protection against the coronavirus and other germs, according to the CDC. That’s because soap and water kill SARS-CoV-2 by dissolving the virus’s protective outer membrane.
Hand sanitizer is especially less effective if your hands are visibly dirty or have food on them because the proteins and fats in food tend to reduce alcohol’s germ-killing power. This is one of the main reasons soap and water are still favoured in the food industry.
You can read more about how hand sanitizer works here.
Related stories about sanitation and keeping clean:
- Does dish soap kill germs? Here’s the best way to clean your dishes
- The household cleaners that you should never mix at the risk of creating toxic gasses
- How do viruses spread and how to protect yourself against infection
- Does bleach kill germs? Yes, but you need to let it sit for 10 minutes
- Chlorine kills germs, but its most effective in your pool
- What temperature kills germs? How to use heat properly to get rid of bacteria and viruses
- Does UV light kill germs? Getting an at-home sanitizer may be worth it
- Does alcohol kill germs? Yes, as long as the solution is strong enough
- Does vinegar kill germs? It isn’t the best disinfectant for viruses