Carbon monoxide danger with pellets (storage + combustion chamber) in living spaces?

CO can be formed in the [lager] from natural decomposition processes. Therefore, the [lager] should be well ventilated.

If these things are observed and there are no obvious leaks, I would not worry about neighboring apartments. CO certainly does not diffuse through a solid wall, as long as there are no extremely high concentrations in the [lager]. One should ensure that the [lager] is truly separated from the living spaces (no pipes running through the walls ...). Then, IMHO, a CO detector in the [lager] and near the boiler is sufficient. I see no reason for CO detectors in the apartments. Please discuss details with the chimney sweep.

Dust explosions are also possible in the [lager], better not to enter with open light ;-).

There is the firing regulation (which prescribes the ventilation openings) and the exhaust measurements by the chimney sweep. There are limit values for how much CO is allowed to be produced. Why does CO form in the pellet storage, nothing burns there?

this is not about a malfunction or similar of the burner and gases escaping because of that. it is about the fact that CO (and also other gases such as aldehyde) is formed in the pellet storage or emitted by the pellets. this happens due to the special manufacturing process of the pellets, which sets chemical processes in motion. it’s all quite easy to find on Google and the pellet lobby has even admitted this by now.

CO certainly does not diffuse through a sealed wall as long as no extremely high concentrations arise in the storage.

well, that is now questionable or has even been partially proven, that CO indeed diffuses through ceilings and walls. so apparently it does not necessarily require cracks, holes, or the like.

so this is now questionable or has partially been proven that CO actually diffuses through ceilings and walls.

That may be true, I do not deny that, but what partial pressure difference is required for this? In my opinion, nothing diffuses through a wall of normal modern construction from a well-ventilated storage room. If a concerning CO concentration should develop in the storage, the detector will alarm. At the latest then, you have to ventilate. If that is not possible (for whatever reason), adjacent residents can still be woken up from their sleep. *Storage in the basement, above it the ground floor apartment. Between them, from bottom to top: reinforced concrete ceiling, insulation, foil, staple board, heated screed, top covering. The CO transport through this "wall" will not be measurable as long as no CO pressure storage is operated in the basement.*

I also think that if diffusion takes place, the concentration will be very low and I would rather be concerned about the microwaves from the neighbor ;)

In short, regards