🤙🏼 🏚️ 🛥️ The best materials for the independent manufacture of medical masks 👠 🐺 ⛑️

During a coronavirus pandemic, masks in pharmacies are instantly sold out, and many people have to do what some scientists call the “last resort”: homemade masks.

Data shows that some makeshift masks successfully stop viruses. But if you have to make a mask yourself, from what material is it better to make it? During the spread of the coronavirus in China, many retailers began to talk about making masks from napkins, kitchen towels, cotton cloth, and even oranges!

What material is best to make a homemade mask

Researchers at the University of Cambridge have tested a large number of home materials from which to make a mask. To measure effectiveness, they bombarded masks with Bacillus atrophaeus bacteria (size 0.93 to 1.25 μm) and Bacteriophage MS viruses (0.023 μm) various household materials.

They measured the percentage of microorganisms capable of retaining material and compared the performance with a conventional surgical mask.

Unsurprisingly, the surgical mask, which intercepted 97% of bacteria with a size of 1 μm, proved to be the best. However, almost all materials were able to filter at least 50% of the particles. Filters for a vacuum cleaner (95%), kitchen towels (83%) coped best [thick cotton fabric / approx. trans.], clothes made of fabrics mixed with cotton (74%) and clothes made of 100% cotton (69%).

Homemade anti-virus masks

However, bacteria were used in the test with a size of 1 μm, despite the fact that the size of the virus is 10 times smaller. Can homemade masks filter out smaller particles? To answer this question, scientists tested 0.02 μm Bacteriophage MS2 particles (5 times smaller than coronavirus).

On average, homemade masks stopped 7% less viral particles than bacterial particles. However, all home materials were able to stop 50% of viruses or more (except for a scarf with its 49%).

Does double-layer masks improve performance?

If the problem is filtering efficiency, will masks work better if we make them two-layer? Scientists tested viral particles on two-layer versions of masks from kitchen towels, pillowcases and cotton t-shirts.

In general, doubling the layers helped a bit. The doubled pillowcase layer caught 1% more particles, and T-shirts - 2% more. However, a double kitchen towel improved by 14%, eventually achieving the effectiveness of a surgical mask.

Judging by the data, the best materials were a kitchen towel and a filter for a vacuum cleaner. However, the researchers did not consider them the best materials for homemade masks. Instead, their work indicates that the best materials are a pillowcase and T-shirt made from 100% cotton. Why?

The importance of ease of breathing in a mask

The answer is how easy it is to breathe in the mask. This is an important factor affecting your comfort. And comfort is not just luxury. Comfort will affect how long you can wear the mask.

Fortunately, in addition to particle retention efficiency, the researchers studied the pressure drop for each type of tissue. This is a good indicator of how easy it will be to breathe through each of the materials. Materials were compared with a baseline surgical mask.

Although a dishcloth and vacuum cleaner trap most of the particles, it is most difficult to breathe through them. It is more than twice as difficult to breathe through two layers of a kitchen towel than through a surgical mask. But breathing through a pillowcase, t-shirt, scarf and linen is easier than through a mask.

Best Material for Masks: Researchers' Choice

Based on the percentage of particles captured and the ease of breathing, the researchers opted for cotton T-shirts and pillowcases as the best options for homemade masks.

Can other materials be used? Cambridge researchers missed one common piece of paper: paper towels. We checked how well these masks retain particles smaller than microns. [ Spoiler: bilayer retains 33% of particles with a size of 0.3 microns and 72% of particles with a size of 2.5 microns / approx. perev. ].

Making homemade masks from home materials

Bottom line: test data suggests that the best choice for a homemade mask would be cotton t-shirts, pillowcases, or other cotton materials. They filter out about 50% of 0.2 micron particles, which roughly corresponds to the size of the coronavirus. It is also easier to breathe through them than through surgical masks, making them more comfortable to wear for several hours.

Doubling the layer of material of a homemade mask very slightly increases the degree of filtration, but greatly complicates breathing through it.

Note perev .: One of our hygienists recommended buying a covering material for greenhouses, which is the same spanbond from which medical masks are made, and cut masks from it.