FACE MASK WITH UNIDIRECTIONAL VALVE

摘要

Face masks that include a unidirectional valve are disclosed. The unidirectional valves permit fluid communication between an interior gas space defined by the mask and the wearer and an exterior gas space outside of the face mask. The unidirectional valves includes one or more valve flaps positioned over an opening formed in the base of the valve. Each of the valve flaps includes a free edge and a hinge located generally opposite from the free edge.