Is the ventilation system contaminated with germs?

What does the facility look like as a whole?

Would you like another photo (larger image section) or a description of the system?

Rain could of course be an issue. The air intake is in the west and there is always some wind there that possibly pushes the rain under the slats.

I consider that rather unproblematic. A little rain moisture blown through the slats dries quickly again due to the air currents. No way do 200l of water accumulate there. Spontaneously, I would guess that the pipe is damaged and accumulating seepage water is penetrating. Or (sounds wild now, but who knows...) someone has connected a rainwater downpipe to it. I would do a camera inspection.

So now to the actual question: we have been constantly having colds for about 6 weeks. When one stops, the next one starts.

Surely there are some people experiencing the same right now. But it certainly isn’t healthy.

Would you like another photo (larger section of the image) or a description of the system?

The entire system and not just the section with the pipe. I am interested in how the condensate drain is designed. Regarding the air well: Are there exterior photos of the construction before it was filled in? Is it ruled out that the excavator driver drove over it while filling? Are the transitions between the pipe and the intake executed cleanly?