Pilot Physiological Evaluation of an Investigational Mask with Expiratory Washout.

Inclusion Criteria: * No indication of intubation upon evaluation by physician in the next 2 hours * Fits the investigational mask Specific for hypercapnic patients 1 of the following criteria * Patients hospitalized with acute respiratory failure (ARF) stabilized and tolerating NIV or; * Patient admitted to hospital with ARF with one criteria for NIV among the following: * Acute hypercapnic respiratory failure with hypercapnia and acidosis (Partial pressure of arterial carbon dioxide (PaCO2) \> 45 millimeters of mercury (mmHg) and pH \< 7.38) or * Post-extubation period within 48 hours, in patients with high risk of re-intubation Specific for hypoxemic patients 1 of the following criteria * Hypoxemic respiratory failure without hypercapnia requiring nasal high flow or; * Hypoxemic respiratory failure without hypercapnia requiring NIV or; * Conventional oxygen therapy (COT) \> 6 liters per minute (L/min) with peripheral oxygen saturation (SpO2) \< 92% Exclusion Criteria: * Refusal to participate in the study * Inability to provide informed consent * Infectious isolation * Facial deformity, burns or morphology that prevents adequate mask placement * Claustrophobia * Nausea * Presence of nasogastric tube * Pneumothorax * Confusion or loss of consciousness * Severe upper gastro-intestinal bleeding * Any other condition, which at the investigators discretion, is believed may present a safety risk or impact the feasibility of the study or study results