Breathing assistance apparatus

A mask assembly for use as part of an apparatus for supplying a flow of respiratory gases to a user comprising:

• a rigid mask body comprising an inlet through which the flow of respiratory gases are provided to an interior of the mask assembly, the rigid mask body comprising an annular channel facing toward a user in use, the annular channel defined between an inner wall and an outer wall, the outer wall of the annular channel having a plurality of apertures connecting an interior of the annular channel with atmosphere on an exterior of the rigid mask body, the plurality of apertures on the outer wall being oriented so as to direct air from the interior of the annular channel to the exterior of the rigid mask body;
• a mask seal assembly comprising a rigid clip and a flexible seal;
• the rigid clip comprising an inner surface and a ramped surface, the ramped surface configured to snap fit with the rigid mask body;
• and
• the flexible seal comprising a proximal face contacting portion configured to substantially seal against a portion of a user's face surrounding at least one respiratory orifice of a user in use and a distal clip contacting portion, wherein the distal clip contacting portion extends along at least a portion of the inner surface of the rigid clip;
• the mask seal assembly further comprising a flexible rim extending from the distal clip contacting portion of the flexible seal, the flexible rim configured to sealingly engage the outer wall of the annular channel, when assembled.