A new report has found that the popular KN95 mask is not as effective as FFP2 masks, which are rare.
In the proof-of-principle study, they compared a variety of commonly available types of mask and found that no mask type came close to the performance of a standard surgical mask and it offered very little protection.
The study found that a single-layer mask (such as one made with tea towels) reduced exposure to various activities, but decreased the mask's effectiveness over a three-hour period. Additionally, multi-layer masks were considered to be more protective than single-layer masks.
These measurements cannot be representative of the actual performance of a single layer mask, but rather the effect of different types on the effectiveness of the mask.
But even the best homemade ones aren't as effective as surgical masks, according to Cole. The surgical masks They are a very good option to protect people from COVID-19 because their filtering effect is extremely high.
These masks fit more closely and are made of higher filter material than conventional masks, as they can filter an estimated 95% of airborne particles that could otherwise pose a threat to human health. These high quality filter masks protect the wearer from infection and due to their filtering effect they are also more likely to pass through more air pollution than the normal mask.
However, there is no broad consensus on the efficacy of self-made masks made with different types of substances in minimizing disease transmission. Some studies have investigated its efficacy against COVID-19, but all have focused on masks that interrupt disease transmission.
In a recent prospective group-based study, Cole and colleagues at the University of California, San Diego School of Medicine compared the effects of two different types of masks on the transmission of COVID-19 and other respiratory diseases.
The study examined 14 different types of face coverings, including surgical masks (suitable or inappropriate) and the so-called neck warmer / balaclava, which are often used to protect the face from the wind. Half of the masks with a true filter effect were surgical-looking masks.
A large dispersion of filter efficiency was observed among the different types of disposable masks with different filters. A study that examined N95 masks from different manufacturers found that more than 90% of the masks in their study were leaked. When the test parameters for NIOSH certification were measured, the collection efficiency of the filters from the surgical masks it ranged from less than 10% to almost 100%.
In summary, N95 masks meet the US standard for NIOSH respirators and the FFP2 it is very similar in Europe. The KN95 mask is a standard Chinese mask, and the GB-T 32610 standard daily mask (70%) is another mask that can look similar to a surgical mask.
The level of protection depends on the type and type of respirator, see this section for more information on the types. A face mask provides protection for the user, but the level of protection depends on the type of mask.
Burken says the effectiveness of fabric filters depends on the material used, but generally adding a filter is more protective. The good efficiency of the filter is very useful in the manufacture of cloth masks, since it is too difficult to breathe through the respective material. Adjusting this is important for COVID-19, which protects against a variety of respiratory diseases such as bronchitis, asthma, and respiratory infections.
Therefore, a mask is needed to prevent viruses from entering and exiting, which is done by high filtration surgical masks for healthcare workers. Such a leak can significantly reduce the effectiveness of the mask, but only if used correctly, Burken said.