The Only Time You Should Hold Your Breath

A video clip that has gone viral offers a sobering reminder that air trapped in a cave (or in any other place such a shipwreck) may not be fit to breathe. Experienced cave diver Jeanne Edgerton was exploring a cave system in Mexico with her husband and others when they surfaced inside a fairly large air dome.

On the surface, the hose from her tank to the BC became unattached and she had to struggle to stay afloat. Breathing hard without her regulator in her mouth, she was becoming asphyxiated in the oxygendeficient atmosphere. Thankfully, her husband, Brian Wiederspan, got the situation back under control by getting her to breathe from her regulator after other members of the group had failed to convince her to do so.

Of course, divers should keep their regulators in their mouths when surfacing in any untested air pocket. goo.gl/2hfYEK