I have questioned the social distancing of 1.5-2 meters as way too close already last year, and said that it does not protect against standing and slowly wallowing aerosol clouds in enclosed compartments and room.
Wioth slow air cleaning, 8-10m.
FFP2 masks do indeed not fulyl prevent infecitons, but as their specificaiton says, FFP2/KN95 standard must filter 19 out of 20 particles. actually good quality FFP2 filters filter even almost 99% if correctly worn.
They trick is that
any cloth you wear will reduce the virus load durign an exposition. Some do that more, some do that less. The virus load correclates with the severity of the developing case, since more virusses infecting on exposition shortens the time the immune system is left with to adapt before virus numbers overwhelm the organism. Any reduction of virus load works the probabilties in your favour. Even a sheet of paper will do that, although not too efficient, but they deflect parts of the air stream blwon into your face directly. But if you stay aorund, the aersols surroundign you nevertheless will reach deep into your breathing system. Aerosols in the air can stand there for long time to come, and that'S why it is important to not stay in them for long. The filter on your face then will only extend the time until virus load you inhale becomes critical.
What is so difficult in these things. I dont get it.
Imagine a winter day, you leave the house, and breath in and out, coming out of the warmth. What happens? You seem to breath out a cloud of fog. Thats is aerosol. When a smoker stands near by, you smell the burning tobacco, that is another, even finer aerosol, even if there is no smoke visible. As long as you smell it, there is aerosol . A weather mist, a fog that forms up out there, also is a form of aerosol - and it stands in the sky for hours, that fine it is, it does not just drop down to the ground - if it would, it would be called rain and the water "particles" would be much greater, being pulled down by their own weight.
Small particles hold a smaller virus load each of them, but they get inhaled much deeper into the lung, and so are considered to be more dangerous. Bigger particles hold bigger virus loads, but are not getting inhaled as deep into the lung.
Virus load during exposition is a key variable. Keep it low by the means available to you. Distancing, limited time to stay, wearing masks.
14 months and one sitll needs to explain the most simple basics. Unbelievable. Hopeless.
And the other thing. Some of the vaccines , or even just one, was confirmed to give sterile immunity, means: the person cannot be carrier and infect others while not getting ill himself. The others give the described vaccination protection to the person (their immune system is "live"), but they can still be carrier and infect others. Thats why it makes sense to argue that vaccinated people should not run aorund with unvaccinated people.