Handwashing 101: A Guide To Proper Washing (And Drying)

Coronavirus fears have health professionals talking once again about the importance of washing your hands. Here's a primer on the proper technique — and some of the science — of cleaning up.

ARI SHAPIRO, HOST:

We take hand-washing for granted. We do it every day as a first step in preventing the spread of infection like the flu or the new coronavirus. But are you washing your hands the right way, and are you washing them long enough to really protect yourself? We wanted to try to understand the proper technique behind hand-washing, so Mary Louise spoke with Maddie Sofia, host of NPR's daily science podcast Short Wave.

MARY LOUISE KELLY, HOST:

Hi, Maddie.

MADDIE SOFIA, BYLINE: Hey, Mary Louise.

KELLY: Hey. I should explain. I have managed to sneak out of the studio. We have come down to the second floor kitchen of NPR headquarters because there is a sink.

SOFIA: Sure is.

KELLY: And we're going to do this.

SOFIA: Yes. We absolutely are.

KELLY: Would you start by just explaining the why?

SOFIA: Sure.

KELLY: I mean, we all know we're supposed to wash our hands.

SOFIA: Yeah.

KELLY: But is this really keeping us and everybody else from getting sick?

SOFIA: Yeah. So it's actually one of the easiest and most effective ways to prevent getting sick. So a lot of the germs that we worry about get in through our nose and mouth, so if your hands are dirty, that's a problem. And we touch our face a lot. There've been a few studies that show it's more than 15 times per hour.

KELLY: Oh, my God.

SOFIA: So yeah, it's horrifying. We're gross. And so you definitely want to keep those hands clean.

KELLY: In preparation for this, in boning up...

SOFIA: Absolutely.

KELLY: I went online. I watched a video that our editors have sent around. It kind of terrified me because I'm not doing 90% of the things...

SOFIA: Yeah.

KELLY: ...You should be doing. It was super-complicated.

SOFIA: Yeah. The instructions for places like the World Health Organization are very intense and will make you feel like you've never washed your hands the right way ever. But the important thing is to do it for long enough, to do the basics. Get the soap everywhere. And if you do that, you're probably OK.

KELLY: OK. Let's do it.

SOFIA: OK.

KELLY: Here we are.

SOFIA: All right. You ready?

KELLY: NPR sink.

SOFIA: First thing you're going to do - get your little hands wet.

KELLY: Does it have to be hot?

SOFIA: No.

KELLY: No. OK.

SOFIA: Actually, it doesn't at all.

KELLY: OK, so just lukewarm, room temperature.

SOFIA: Yep.

KELLY: All right.

SOFIA: So first, you get your hands wet.

KELLY: I will.

SOFIA: You can turn that water off. We're not trying to waste water here.

KELLY: OK. Yeah.

SOFIA: And then get some soap on your hands.

KELLY: OK.

SOFIA: And that can be any type of soap. It doesn't need to be antibacterial. It doesn't actually help.

KELLY: Just...

SOFIA: It's not better.

KELLY: Really?

SOFIA: Yeah, seriously.

KELLY: Just soap - I got the soap.

SOFIA: So lather that soap up.

KELLY: All right. So...

SOFIA: You want to get it all over.

KELLY: This is the extent of my usual hand wash.

SOFIA: Yeah.

KELLY: You're seeing it.

SOFIA: So yeah. So...

KELLY: Yeah.

SOFIA: We're going to go a little more intense today. And so now you want to start kind of scrubbing your hands, and you want to do this for at least 20 seconds. So you can sing "Happy Birthday" twice. That's something people do.

KELLY: (Singing) Happy birthday to you.

SOFIA: So start with your - like, your palms like you're...

KELLY: Yeah.

SOFIA: ...Going to, like, roll up a meatball or some cookie dough.

KELLY: Got it.

SOFIA: And then you want to turn over one hand and use your other hand to get the backs of your hands and lace your fingers through.

KELLY: Ooh, I never do that.

SOFIA: Yes. Yeah.

KELLY: OK.

SOFIA: Perfect. Perfect. And then you want to get around your thumbs.

KELLY: OK.

SOFIA: And then the last thing is just - you want to get your nails on the palm of your hand and kind of - you want to get under your nails because germs love under nails. And this friction actually helps actually remove the germs off of your hands.

KELLY: Is that about how long we should be doing it for?

SOFIA: Yeah, just about 20, 25 seconds - if you're showing off, 30 seconds.

KELLY: OK (laughter) - competitive handwashing.

SOFIA: Yeah. Well, I mean...

KELLY: Yeah.

SOFIA: We're here to win.

KELLY: And now we rinse.

SOFIA: And then you just turn the water on.

KELLY: Same thing.

SOFIA: Rinse your hands. Yeah.

KELLY: It can be hot. It can be cold.

SOFIA: Yep. Yeah, you can turn it off with your wrist. You can actually turn it off with your hands. You don't need to use a paper towel. It's - you're totally fine to touch the faucet again, actually.

KELLY: OK. All right.

SOFIA: And then this is important. You want to dry it because your hands are actually better at transmitting germs when they're wet than when they're dry.

KELLY: It makes sense.

SOFIA: Yeah.

KELLY: Yeah. If I'm running around, if I'm not at a sink, if I'm back in the studio and Ari coughs on me...

SOFIA: He would, too.

KELLY: He would. He's just like that. Hand sanitizer - is that just as good?

SOFIA: Yeah. It's not quite just as good. Some germs can stick around after hand sanitizer, but it's absolutely better than nothing. You just want to make sure you're using some that has more than 60% alcohol in it. So the alcohol content is pretty important. And in the same case, you want to get it - a lot of it on, and you want to let it dry. You don't want to wipe it on your pants afterwards.

KELLY: Yeah, you definitely do not...

SOFIA: You don't do that in general.

KELLY: ...For all kinds of reasons.

SOFIA: Yeah.

KELLY: Maddie Sofia, thank you.

SOFIA: You're welcome.

KELLY: She is with our daily science podcast, Short Wave.

(SOUNDBITE OF LCD SOUNDSYSTEM SONG, "DANCE YRSELF CLEAN")

Copyright © 2020 NPR. All rights reserved. Visit our website terms of use and permissions pages at www.npr.org for further information.

NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.