A blower includes an electric motor having a shaft, a housing having an inlet and outlet between which is defined a gas flow path, the outlet structured to direct gas exiting the blower in an axial first direction, a first impeller attached to the shaft and adapted to accelerate air tangentially and direct it radially outward, a stationary portion, and a shield. The stationary portion includes a first stator vane structure defining a plurality of stator vane leading edges and a stator vane outer radial edge. The first stator vane structure is arranged to direct gas flow along a curved path that directs flow at an inner end thereof in a radially inward direction. The shield has an outer edge extending radially beyond the outer radial edge of the first stator vane structure and is adapted to isolate the stator vane leading edges from an impeller blade pressure pulse.
