anytime you go out now,

but masks are in short supply in a lot of places,

and there's a push to preserve medical masks

for medical workers who are putting themselves at risk.

So we talked to experts about the best way

to make and wear a mask at home.

Before you actually make any masks at home,

you should take some precautions.

Nishi Viswanathan: Basic precautions like handwashing

of course, like, before beginning work,

and disinfecting the surface

with anything that indicates that it can kill viruses.

Something practical would be to wear a mask yourself

if you're making masks.

Narrator: Viswanathan also recommends washing your fabric

in hot water before making masks.

This way the fabric will be clean

and also won't change in size again.

While there are several materials being recommended

for masks by experts, overall...

Raina MacIntyre: You want a material that repels water,

not one that absorbs water.

So, a normal surgical mask, for example, is water resistant.

So you want something that repels water

but that's still breathable.

Narrator: There are a lot of different

mask designs available, but we're gonna show you

how to make the three recommended by the CDC.

You can make this first one using a T-shirt.

Again, a cotton-polyester blend would be best.

You cut off the bottom of the T-shirt,

cut out tie strings, and then tie it around your head.

This next design can also be made with a bandana

or any square cotton cloth that's 20 inches by 20 inches,

along with two hair ties or rubber bands.

Add the hair ties to both sides,

tuck in the bandana ends,

and then you're all set.

This third design requires a sewing machine

to make a relatively simple mask

from some kind of cotton fabric

and elastic pieces or string or hair ties,

whatever you have on hand.

You cut two 10-by-6-inch rectangles of cotton fabric

and stack them to sew them together.

You fold and hem the long sides,

then the same on the short sides.

Next you add 6-inch elastic pieces or something similar

through the hems and tie the ends.

Tuck the knots in the hem and stitch the elastic into place.

If you have access to a sewing machine,

some experts recommend taking things a step further

by following a design with more layers

as well as a pocket for a disposable filter.

MacIntyre: So, having three layers is best.

In some of the designs, you can make a pouch in the front

where you put a disposable filtering.

And if you can get hold of disposable filters,

then that's a good option as well,

because those filters are designed

to be like a respirator in essence.

Narrator: Sudeb Dalai, a Stanford physician specializing

in infectious diseases, recommends masks with filters

for people who anticipate prolonged exposure

or close contact with other people,

are taking care of someone with COVID-19,

or have an underlying condition.

To make a filter, Dalai recommends

using polypropylene material or HEPA vacuum bag filters

because they're breathable but still effective

at filtering tiny particles.

Dalai also says to make sure any filters are placed

between two layers of fabric to protect your skin

as well as to prevent breathing in the filter material.

Regardless of the design, you're gonna wanna make sure

that your mask fits properly.

MacIntyre: So, it should fit around

the contour of your face.

Whether you use the elastic or any other material

to help mold it around the edges, that will help,

because otherwise you get a lot of air leakage

through the sides, and when you breathe,

the air will just follow the path of least resistance.

So if the sides are flapping open,

it'll just go in through the sides.

Narrator: It's also important that your mask fits well

so that you aren't touching it

again and again to readjust it.

Viswanathan: It has to extend to

the top of the bridge of the nose

and then below the chin.

So it has to provide adequate coverage

and has to sit comfortably on the nose

without, like, sliding off.

MacIntyre: The process of putting on and taking off the mask

is also really important

because the mask can become contaminated.

So if you're out and about and you want to store your mask,

it's better to use something like a Ziploc bag.

Just keep it in your pocket

rather than just putting it in your pocket

because the mask itself could be contaminated.

Narrator: So, you should be washing your hands

before and after touching your mask

as well as cleaning it after every wear.

Viswanathan: One thing to remember when wearing masks

is that they are not substitutes for social distancing.

So definitely follow the social-distancing guidelines

that you have been following all along.