Cross contamination control

Dear members,

can anyone clarify my query?

I will tell you in detail the facility design. I understand that its difficult to visualize the scenario w/o drawing.

The facility is of multiproduct OSD facility with individual AHU for each area and the corridor which are independent. All the processing rooms have no air lock and are provided with heavy duty doors to maintain pressure differential –ve w.r.t corridor.

To be clear the corridor is like an aisle where both the sides there are processing rooms with no air locks but with heavy duty doors and the processing areas maintained –ve w.r.t corridor.

there are no toxic products produced as such. Granulation is of laminar flow type to avoid dust generation and having dust extractors so that sifting and milling activity can be carried out near the dust extractor. And the other areas r of turbulent type as there is no dust generation.

The corridor connecting all the processing areas is the same for entry and exit of personnel from processing areas.

Now the concern is how to prove that there is no cross contamination involved?

Are there any chances of continuing with the same facility w/o any major modifications.

But I want to know how to challenge that there is no cross contamination involved till date.

I would be thankful if you can reply.