Since the emergence of the Coronavirus, the protective mask has become an essential product to restrict the spread of the epidemic as much as possible. Whether it is approved "FFP2", surgical or simply "homemade", the materials used to make it are the subject of debate and everyone has their own opinion.
In order to put the church back in the middle of the village, researchers from the researchers from the University of Cambridge tested the effectiveness of several everyday objects and materials on two parameters, the level of protection and breathability, in order to identify the one that represents the best everyday defence against bacteria. To do this, they sprayed the Astropheus bacteria (about 1 micron) and the MS virus (0.02 microns) on the materials to be tested and analysed their level of capture. For information, the Coronavirus particles have a size midway between the two particles tested, 0.1 micron.
While the surgical mask offers 97% effective protection against particles larger than 1 micron in size, the 100% cotton t-shirt (one layer) offers "only" 69% protection while a simple vacuum bag will offer almost the same protection as the surgical mask, 95%.
What about smaller particles?
By spraying the MS virus particles (0.02 micron, five times smaller than the Coronavirus), the protection of the 100% cotton t-shirt drops to 51%, compared to 89% for the surgical mask and 86% for the vacuum cleaner bag.
How about doubling the layers?
Doubling the number of protective layers against Astropheus particles has variable effects depending on the material tested. The protection of the surgical mask does not increase, that of the 100% cotton t-shirt only increases by 2% while that of the kitchen towels increases by 14%.
Looking at these figures, the vacuum bag and kitchen towel appear to be the best materials to produce a non-surgical mask. However, the 100% cotton pillowcases and t-shirts were the winners. Why ?
Protection and comfort are the two criteria defining the quality of a mask. A mask offering good protection but whose density blocks the breathing of its user will be of no interest, as on the contrary, our hospitals are already overloaded. To do this, the researchers tested the variation in pressure at the outlet of the different materials during spraying. Here is the result.
The kitchen towel and vacuum bag block the passage of air more than twice as much as a surgical mask. The 100% cotton t-shirt and pillowcase, in 2 layers, have a breathability equivalent to that of a surgical mask.
3. QWALIS mask protection
The fabric used to produce a 100% cotton t-shirt is therefore one of the best compromises to make an effective and comfortable protective mask. Nevertheless, this study does not specify the technicality of the 100% cotton product used during the tests. At Qwalis, we manufacture our masks with the same knitted fabric used to make our t-shirts. Moreover, we guarantee the use of the best quality of yarn, the "30" thread, for a very dense, tight knit, and a minimum weight of 150 to 170 grams per square meter. This for maximum protection, certainly superior to the tests carried out, while maintaining a great comfort of use.
Certification and homologation
Our masks are made according to the recommendations of the French standard AFNOR Spec S76-001 (barrier mask) and the Belgian standard NBN/DTD S 65-001:2020 (community mask).