The system's ventilation must be carried out very carefully. On the one hand, the fermentation gas from the septic tanks must be removed, and on the other hand, the proper ventilation of the BIOROCK treatment unit must be assured.
The diameter indicated in the BIOROCK instructions is 100 mm. This is the European standard and it is from that perspective that the BIOROCK system has passed initial certification tests and operates in other countries.
The 110 mm diameter used extensively in the United Kingdom is a minimum. As a means of taking the necessary precautions, as with the installation of any sanitation ventilation system, there should be no 90° bends. The system will operate perfectly with 45° bends with no reverse slope. The diameter of the inlet lines in the septic tank must be at least equal to the diameter of the building's effluent discharge outlet.
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