Hi, I'm Jeremy Howard from Masks For All, and I've got a quick demonstration here about why it's so important that you wear a mask. Your mask protects me. My mask protects you. Here's how. When I speak, tiny droplets of water come out of my mouth. And I am going to simulate that with a spray bottle.

It's not a perfect simulation because this is actually going to be a lot more spray and slightly larger droplets even than my talking. But it's much closer than like an aerosol can, which is explicitly not what happens when we talk. They just come out of our mouth at a fairly gentle rate.

So here's what could happen when I talk. If I spray this close to the mirror here, then as I spray, you can see what happens. If you zoom in here, you'll see little droplets up here. So what happens if I step over here and try it with a mask?

So let's do the same thing now with a mask in front. And this is the place here, and as you can see, zero droplets. So if I show you this mask, this is the classic T-shirt mask, which actually I haven't even put the paper towel in the middle, which I often use.

And here's what happens if we use just a paper towel. Again, if you have a look, no droplets coming through. So as I said, this is not a perfect simulation of the micro droplets that come out when I speak, but it's the closest we can get without using special laser-based equipment, which is what the scientists who have also done this much better than I have used.

But hopefully this explains why it is that if you're not wearing a mask, remember, you don't know if you're sick because you're most infectious in the early days when you have no or few symptoms. So if you don't wear a mask, then those micro droplets are going on your family and your community members.

So please wear a mask when you make it home. Thank you.