Some time ago, I published an article reviewing the recommendations regarding the making and wearing of surgical masks made in a homemade way. 

A lot of information circulates about their effectiveness, composition, shape... and sometimes this information is distorted or even completely false. So I took up my pen to review the situation and provide advice from the scientific community.

Let's start with the effectiveness of masks.

The Belgian Royal Academy of Medicine recommends wearing fabric masks.
Why?

• these masks filter about 70% of viral particles and therefore serve as a collective protection tool beyond individual protection
• the shortage situation on the industrial-quality surgical mask market (filtering about 89% of viral particles) leads us to reconsider the distribution priorities of these masks. It is clear that these must be reserved for healthcare workers (as well as FFP2 and FFP3 masks, which filter 99%), until supply normalizes.
• they are inexpensive, easy to make, and serve as an effective substitute for people working in low-contamination environments.

How to make your mask?

The AFNOR, the French standardization agency, offers a complete downloadable file on its site.
Here is a practical summary with the assembly range below. Follow me, let's go!

1. Type of mask

The current recommendation from AFNOR is:

• the pleated mask with square dimensions of 20cmX20cm
• the duckbill mask.

I chose to present the pleated one which in my opinion is the most practical.

I recommend making your basic pattern on thin cardboard, this will make tracing your fabric pieces easier and you can reuse it many times without it getting damaged.

Refer to the photo below for:

• place A2 at 2.5cm on the lateral edges on each side of the mask
• place a mark at 5cm in the same way
• place A1 at 7.5cm

Proceed the same way, turning your cardboard to place B2, a mark, and B1.
A1 and B1 are 5cm apart.

2. Choice of fabric
The industrial standard is 120 threads.

If you have fabric at home, choose a cotton fabric with a fairly tight weave.

A test is to hold your fabric up to the sun, light should pass through (because it is not blackout fabric, it is normal that light passes) but you should not see the sun rays through the mesh. If you see small squares forming, it is not good. 

The fabric must be flexible to fit the shape of the face and must be comfortable. 

You can cut 2 or 3 layers of fabric as you prefer.

3. Assembly

After carefully washing your hands, here are the steps to follow to make your mask.

First step: cut two or three fabric squares of 20cmX20cm.

Second step: Assemble the fabric squares right sides together, sew at 1 cm all 4 sides of the squares. 

Then, overlock this seam.

Third step: 

Take your pattern cardboard and mark the folding marks (A2, A1...) with chalk.

Make the folds according to AFNOR instructions, that is, overlap A2 on A1, the mark between A1 and A2 is the folding mark.
Proceed the same way for B1 and B2.

The fold is pressed towards the middle of the mask, you should get a rounded fold on the front side of the mask and a hollow fold on the back side of the mask.

This step must be done on the side you want visible.

Fourth step:

Add the elastics:

• or on the short sides if you want to pass the elastic behind the ears (shorter elastic +/- 20cm for each side)
• either on the long sides if you want to pass the elastic behind the head (longer elastics +/- 35cm for each side)

Check the placement of the elastics carefully (they should not twist) and if their length fits the person's face shape.

Stitch the fold and elastics at 1cm. Make a backstitch (a forward and backward stitch) to secure the elastics well.

If you run out of elastic or bias tape, homemade fabric ties, ribbons... can be a substitute. You will then need to sew 4 pieces (leaving the end of the tie free) so you can tie knots and adjust the mask (since there is no elasticity).

Fifth step: make a 1.2cm fold along the long edges of the mask and stitch at 1cm.

Ta-da, your mask is ready to wear!

How to use your mask effectively and safely?
If handmade fabric masks filter about 70%, it is necessary to treat them properly. Indeed, a mask used or positioned incorrectly can itself become a source of contamination/spread. It is therefore important to follow basic hygiene rules by washing your hands before placing your mask on your face.

The Academy of Medicine reminds us of the following 5 tips:

• Wearing the same handmade fabric mask is limited to a maximum of 6 hours.
• It must cover the nose, mouth, and chin to prevent leaks.
• To remove your mask, use the elastics.

Here is my little method for removing your mask:

1. Turn your palms toward you,
2. Fold your fingers except the pinky,
3. Make a small hook with your pinky,
4. From the front of your face, slide your pinky into the elastic and lift the elastic over your ears, then just slide the mask on.

Simple, right?

This method prevents touching the mask surfaces.

• After removing your mask, you need to wash your hands, counting 40 seconds of washing.
• Wash your mask after use. Currently, the recommended temperature is 80 degrees.

Now you know everything. All that's left is to apply it.

Stay strong everyone!