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human
ELI5: how do divers clear their masks when water leaks in? especially in the case of the 13 thai boys rescued from the caves

I have just been watching Thirteen lives - the film about the cave rescue of the 13 young boys in Thailand who were totally sedated before being taken hours under water.
It got me thinking that when I go snorkelling i always get a bit of water leak into my mask and have to come up and clear it out so i don’t breath water in.
Is this something that happens to scuba divers, if so how do they deal with it, and in the case of the boys how would the divers accompanying them have cleared the boy’s masks ?
i would also like to say what an incredible job done by all those involved.
gpt
Well, for one, remember that scuba divers are breathing through their mouths, so a small amount of water in a mask isn't actually a problem when it comes to breathing. But to clear a mask underwater is actually pretty simple: you inhale air from your regulator, then tilt your head back slightly, lift the bottom of the mask a bit off the face, and exhale the air through your nose. The air bubbles fill the mask and force the water out of it.