The Terrain P.A.P.A® (Positive Air Pressure Attenuator) is a positive pressure reduction device designed to mitigate the effects of positive air fluctuations in the drainage pipework system. As water descends down the drainage stack it creates a negative pressure; if that flow is interrupted or is approaching a change of direction, the negative pressure changes to a positive pressure and moves up the pipe. As the positive air fluctuation approaches the branch off point for the Terrain P.A.P.A® the bladder within the unit reacts quickly and starts to expand, creating a pressure differential at the branch off point. The branch of the Terrain P.A.P.A® then becomes the path of least resistance and the majority of the positive air pressure is absorbed within the unit. As the ambient air pressure within the pipework starts to equalise; the bladder slowly releases the small volume of air into the pipework system, having no effect on the trap seals.
The Terrain P.A.P.A® should always be used with the Terrain Pleura air admittance valves for a complete drainage ventilation system.
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® P.A.P.A.® is a registered trademark owned by Akatherm BV, part of the Aliaxis Group