Fig. 1From: Effects of wearing surgical masks on fraction of inspired oxygen in spontaneously breathing patients: improving safety for frontline healthcare professionals under pandemic situationsa Sampling tube location Ⓒ2021 Hitoshi Sato. No Rights Reserved. b Oxygen mask with a surgical mask Ⓒ2021 Hitoshi Sato. No Rights Reserved. c Oxygen mask only Ⓒ2021 Hitoshi Sato. No Rights ReservedBack to article page