LABSS Information Paper INFOP10 - 2016 Air Admittance Valves
The second paragraph of clause 3.7.8 identifies air admittance valves as an alternative to the requirements of BS EN 12056-2: 2000 as a means of ventilating a drainage system. The guidance makes two provisos relating to the design/manufacture of air admittance valves and their installation in accordance with the conditions of certification of a notified body. With regard to the conditions of certification of a notified body, “a drainage system designed in accordance with BS EN 12056-2: 2000”, means it is to be designed in accordance with the “requirements” of the main body of the Standard rather than the entire code. That is, it is intended to exclude the informative National Annexes.