Asbestos in the flooring of a house from 1972?

I find it interesting that on one hand you are almost panicked about seeing your family endangered, but on the other hand you try to avoid having this floor removed, even though your expert recommends it.

My guess is that you imagine the costs for removal to be too high and therefore fear intangible sums.

My suggestion is: just get quotes from several companies.
It’s usually not that terribly expensive. To cover it up or do a sloppy job, I find very difficult; sooner or later you have to deal with it, even if it’s spontaneous due to a burst pipe causing water damage or something similar. What then?
Have it removed and sleep peacefully.

I find it interesting that on the one hand you are almost panic-stricken about the possibility of your family being endangered, but on the other hand you try to avoid having this floor removed, even though your expert recommends it.

My suspicion is that you imagine the costs for removal to be too high and therefore fear incalculable sums.

My suggestion therefore: simply get quotes from several companies. It usually isn’t terribly expensive. I find it quite difficult to cover it up or do a botched job now; at some point you will have to deal with it, even if it is spontaneously due to a pipe burst with water damage or something similar. What then? Have it removed and sleep peacefully.

You are right about that. What about the living areas? Seven years ago a craftsman renewed them without a mask – bathrooms, floors, new wallpaper, etc. It is of course likely that Kmf was also used here. Is the probability high that this stuff is still in the air today?

And what kind of risk were we exposed to during the renovation? We were on site sometimes in the evenings after work to check the progress. I think we also tore out a floor ourselves (approx. 9 sqm). On the internet I find significantly less about Kmf than about asbestos, but I understand it to mean that Kmf is not as bad as asbestos because it does not remain permanently in the lungs?!

Seven years ago, a craftsman replaced it without a mask [..] Is it likely that the stuff is still in the air today?

Haven't you aired out your place even once in seven years?
Do smells, for example from cooking, remain in your apartment for seven years?

And what danger were we exposed to during the renovation?

How should we know??

You were POSSIBLY exposed once for a short time to a MINIMAL amount of carcinogenic substances, which MAY lead to lung cancer, or simply gets stored in your body. So what? You also breathe in fine dust from traffic daily (mainly tire and brake abrasion, increasing in the future with e-cars). That’s carcinogenic too. Or all the PFC, if you wear that sports or outdoor clothing. All carcinogenic just like a hundred other things you inhale, eat, or come into contact with your body.

But don’t worry, the probability of dying from cancer is currently only 25%.

Long story short: Have your floor replaced by a professional company, otherwise you won’t be able to sleep anymore and will have a bad feeling forever when entering the basement. Completely independent of whether fibers really escape or not.

My suspicion is more that you are afraid of the process of pulling it out - that everything will be released. I can understand that somehow, so let a professional do it, they can surely reassure you. They can tell you exactly when, where, and how to ventilate afterwards, etc... If I were you, I wouldn’t ignore the fact that there is something toxic in your house, it certainly wouldn’t give you peace of mind.

And is Kmf really just as dangerous?

It depends, as always. For over 20 years, KMF have been manufactured differently and are practically harmless. But you have old stuff lying around that can definitely release dangerous fibers (but doesn't have to).

I actually read that unlike asbestos, it breaks down in the lungs after a few hundred days and can also be biologically broken down in the body

Only the newer stuff.

On the Internet, I find considerably less about Kmf than about asbestos, but I think I interpret that Kmf is not as bad as asbestos because it doesn't remain in the lungs permanently?!

"Lung-penetrable KMF (so-called WHO fibers), which were produced before 1996 (so-called old mineral wool), are considered carcinogenic. KMF products marketed from the year 2000 onward are biologically degradable. This means that the fibers dissolve after inhalation and therefore cannot exert their carcinogenic effect." Oh yes, do you and your family eat fries or chips? You should stop quickly, as carcinogenic acrylamide is in them. Talk to a company specialized in remediation and then see how to proceed. It's not always as bad as it seems at first.

My question is just: is the floor intact if it slightly lifts at the edges as visible in the pictures?

Curling can simply result from climate fluctuations causing the surface and substrate layers to react differently dynamically. At some point, the adhesive force was probably no longer adequate for the resulting forces. Re-gluing should be sufficient in this regard. From my point of view, you are making a bit too much fuss about the flooring of a non-living area.