Many of us reach for hand sanitizer foam or gel if soap and water aren’t easily available to clean our hands. In fact, hand sanitizers have become so commonplace that dispensing cannisters can be found in many public spaces, from hospitals to office buildings, nationwide. But are you using the right kind of sanitizer, and are you using it properly?

Here are some points to keep in mind.

First, the Centers for Disease Control and Prevention advises that you use a hand sanitizer that is 60% to 80% ethyl alcohol, the ideal range needed for the product to work. You may see ads or hear suggestions for alcohol-free sanitizers, but these won’t kill germs on your hands. It’s fine to use products that have fragrances or include aloe vera, as long as the alcohol content is present.

Second, when applying hand sanitizer, make sure you use enough to cover your whole hands, not just your palms. Rub your hands together briskly until they feel dry, which should take about 20 seconds. The CDC also urges people not to rinse or wipe off hand sanitizer because the product won’t work correctly if that is done.

Third, make sure you know the difference between when to use hand sanitizer and when to wash your hands with soap and water. Hand sanitizers kill bacteria, but they don’t work on viruses such as norovirus that cause vomiting and diarrhea. Also, they shouldn’t be used in place of soap and water to clean hands that may be soiled with chemicals or dirt.

Hand sanitizers are a safe way to clean your hands in a pinch but, if available, use soap and water to keep your hands clean and germ-free. It’s one small way to have the future of your health … in your own hands.