In this thread everything has already been said, just not by everyone. My estimations about the risk at an event like the ASLOK are based on the fact that I am a medical doctor. Furthermore I have continuously followed the medical literature since the beginning of the Covid-19 pandemic.
What do we know so far about how the Covid-19 virus transmits?
The cases where a large number of people have been infected all look very similar. Usually a group of people were in a locked room. It appears that not all people are equally infectious. While in some cases there is hardly any transmission of the virus, even when people have close contact, there are others that can infect a large number of people. These are the so-called "super-spreaders".
Speech seems to play an important role in the transmission of the virus. Every time we speak, we are releasing aerosols containing viruses. These aerosols have the potential to spread far inside enclosed spaces.
Masks can help to make the transmission of the virus more difficult. But they do not provide 100% protection.
Therefore, airing rooms seems to play a very important role in preventing the transmission of the virus.
Prof. Drosten, a virologist from the Charite in Berlin, said that he would rather be in a well-ventilated room without mask wearers than in a poorly ventilated room with mask wearers.
Ideally, one would speak as little as possible. Also, one should speak as quietly as possible.
On the other hand, the direct contact of people, i.e. transmission through smear infections, seems to play a much smaller role.
My personal conclusion is that attending a tournament like the ASLOK exposes you to an incalculable risk. It has already been pointed out that transmission of the virus occurs at the time when patients are asymptomatic. So everyone who goes to the ASLOK relies on the fact that none of the participants is an asymptomatic virus carrier at that time.
It is also important that not only all participants wear a mask, but also that the mask is worn in a correct way (i.e. mouth and nose are completely covered). According to my observation in the last weeks, 20-30% of all persons are not able to do this.
At work I wear one of the masks that offer high protection (FFP2 / N95). These masks become very uncomfortable after a relatively short time (about 2 hours).
My urgent recommendation is therefore not to hold this tournament as a face to face tournament but to hold the tournament virtually.