When you are on the go and soap and water are not available, alcohol-based hand rubs and sprays that contain greater than 60% alcohol can be effective if used properly.
While a hand sanitizer is useful in a pinch, it can fail under certain conditions.
Hand sanitizers kill germs but they do not clean dirty hands. Hand sanitizers work best when hands are generally clean and not heavily soiled or greasy.
If hands are wet or sweaty the water can dilute the sanitizer and reduce the effectiveness. Also, if hands are dirty or sticky, the sanitizer will not clean your hands of excess oil or grease to which viruses can also adhere.
"Alcohol is pretty effective at killing germs, but it doesn't wash away stuff," says Dr. William Schaffner.
According to the CDC, "There are important differences between washing hands with soap and water and using hand sanitizer. Soap and water work to remove all types of germs from hands, while sanitizer acts by killing certain germs on the skin.
Although alcohol-based hand sanitizers can quickly reduce the number of germs in many situations, they should be used in the right situations. Soap and water are more effective than hand sanitizers at removing certain kinds of germs like norovirus, Cryptosporidium, and Clostridioides difficile, as well as chemicals."
That said, the CDC recommends using hand sanitizer as a first choice in certain situations such as visiting someone in a hospital or nursing home or when interacting with people who have a weakened immune system. Also when going in and out of stores, doctor visits, etc., a spray of an alcohol-based hand sanitizer on your way in and out decreases the chance of introducing a disease-causing bug or leaving with one.
Not all hand sanitizers are created equal
To kill most disease-causing germs, the CDC recommends a sanitizer that is at least 60 percent alcohol. Beware of "sanitizers," sprays or wipes on the market that contain less than 60% or even contain no alcohol at all.
Any product containing less than 60% alcohol may not work as well “for many types of germs,” and could “merely reduce the growth of germs rather than kill them outright,” the CDC says. There is also some concern that alcohol-based "hand sanitizers" or hand rubs with low alcohol content may actually lead to germ resistance.
Baby wipes will not work, antibacterial wipes will NOT kill viruses, and, NO, neither will your bottle of Jack Daniels Whiskey or Tito's Vodka since they are only about 40% ethanol!
You may also find many hand sanitizers that contain benzalkonium chloride as the active ingredient instead of alcohol. These products, however, are not recommended by the CDC, since “available evidence indicates benzalkonium chloride has less reliable activity against certain bacteria and viruses” compared to alcohol-based sanitizers.
How To Use a Hand Sanitizer
Hand sanitizer works best when used correctly.
A hand sanitizer is ineffective if too little is applied or it is wiped off before it has dried completely
Just putting a little dollop in the palm of your hand and wiping quickly isn't good enough, says Dr. William Schaffner.
"You've got to use enough and get it all over the surfaces. Rub it all over your hands, between your fingers and on the back of your hands."
- Apply the recommended amount to the palm of your hand.
- Make sure to cover the entire surface of both hands and distribute the sanitizer all over, paying special attention to the fingertips
- Rub your hands together until they feel dry (this should take around 20 seconds).
- Do NOT rinse or wipe off the hand sanitizer before it’s dry; it may not work well against germs.
- The picture below is courtesy of the World Health Organization
Hand sanitizer precautions
Keep away from small children! Hand sanitizers can be toxic when ingested, especially by children. “Drinking only a small amount” can cause alcohol poisoning in kids, according to the FDA. If you or your child ingests hand sanitizer, call the poison control center or a medical professional immediately.
Do not get hand sanitizers in your eyes.
Hand sanitizer is also flammable. Though the CDC says that the incidence of fires due to alcohol-based hand sanitizer is “very low,” store hand sanitizer in a safe manner away from flames.
If you are concerned about sensitivity do a patch test before using.
Cleaning products are not a substitute for hand sanitizer
Disinfectant sprays and antibacterial cleaning wipes should not be used as stand-ins for an alcohol-based hand sanitizer. Antibacterial wipes do NOT kill viruses and these products are meant for “hard, nonporous surfaces,” not human skin, according to the Food and Drug Administration (FDA).