Disclosed is an inlet manifold member for a centrifugal fan in a CPAP breathing or ventilation device with two concentric outlets for better mixing of breathing gases. The inlet member includes a first inlet for receiving a first fluid flow of air and a second inlet for receiving a second fluid flow of oxygen, the inlet member defining a first fluid flow path for the first fluid flow and a second fluid flow path for the second fluid flow, and comprising a first and second outlet, for respectively the first and second paths, the first outlet being of a ring like shape, the second outlet being arranged coaxially to the first inlet and/or being surrounded by the generally ring shaped first outlet. A housing has at least one inlet housing part being provided with the first fluid flow path outlet and the second fluid flow path outlet. A filter element extends over the whole cross section of the first fluid flow path.
