Simple face mask (Hudson mask) can deliver maximum FiO2 of:-
Simple facemask/ 'Hudson' mask These devices are used very commonly. They are variable performance devices and the maximum inspired oxygen concentration that can be achieved with these devices is up to 60%, but this is very dependent on the oxygen flowrate and the patient's respiratory pattern. The mask has side holes which are designed to allow indrawing of room air during inspiration
0.6
0.4
0.8
1
Airway