One of the first measures taken by the Mexican government against the swine flu was the distribution of nose and mouth caps. Do they really help?
It is good to make a distinction between mouth caps and so-called respirators.
Nose and mouth caps
The main target group for caps are sick people, who can pass their infection on to others. Nose and mouth caps prevent this. They prevent ultra-fine droplets, which can contain viruses, from spreading into the environment when you exhale, sneeze or cough.
However, their sealing is not watertight. They do not protect, as many people think, against inhalation of such particles. But they do prevent you from touching your nose or mouth with your hands and fingers, something that people do very often and completely unconsciously.
dust mask
Respirators, an English term for gas and dust masks, do protect against inhalation of unwanted particles. So-called N95 respirators stop at least 95 percent of all fine air particles.
They are worn during surgical procedures, but also on construction sites with a lot of fine dust. You can find examples this website – at the very bottom of the page – view.
N95 respirators protect against inhalation of germs, but their effect during epidemics is unclear. After all, their use is not obvious.
The flexible masks should be deformed so that they fit closely to the face and virtually all the inhaled air passes through the mask. This is somewhat tiring and makes them less suitable for people with breathing difficulties.
Cons
During epidemics, you never know whether the person in front of you is infected with the virus or not. So you should in principle always wear the respirator.
But over time, they often irritate the skin. Especially in hot and humid weather or when you sweat. They are also moistened by the exhaled air. That makes these masks less pleasant to wear.
And when you wear them a little more casually and less close, the protection decreases, because a large part of the inhaled air no longer passes through the respirator.
Another disadvantage: both masks and respirators are for single use! So you will have to buy big if you want to protect yourself optimally every day.
