Do the interior surfaces of your steam sterilizers no longer comply with their required initial condition? Walls, floors and ceilings have become matte and partly discoloured yellowish to reddish brown?
This medical technology phenomenon has been known to occur for quite a long time. In cannot be ruled out that these deposits on the surfaces of the autoclave chambers transfer to the instruments.
To prevent this process, the steam sterilizers should be cleaned at regular intervals.