Gas dome transfers the produced bio gas to the next biogas plant unit from the digester. The formation of foam in the digester tank is recognized by means of a foam probe. Its signal activates the water spraying system. This prevents a soiling of the gas pipe. The gas dome is fitted either by flanges or is cast into the concrete tank, which is less expensive. Gas doom material is SS316 and the dimension can cover a range between 400 to 800 mm. It has several connections for gas analysis, pressure pickup, and floating bell along with having a reserve connection and viewing glass with wiper.