An interface system for use in providing a flow of pressurized gas to a patient. The interface system comprises a mask (18) structured to engage a nasal and/or oral orifice of a patient, a conduit (16) coupled to the mask, and a valve mechanism (20) operatively coupled to the mask or the conduit. The conduit is structured to communicate the flow of pressurized gas to the mask. The valve mechanism is structured to selectively impede the flow of pressurized gas to the patient and is actuated by the patient, thus allowing the patient to speak without interference from the flow of pressurized gas.
