Rebreather Video

[Tangfish]

Here's a neat video by a guy who recently learned to dive with a rebreather. He details his learning of the basics.

[DiverDown]

For an upcoming piece in Popular Mechanics magazine, I did a rebreather familiarization course and dive. Here's a bit more background than the magazine can hold on rebreather technology. I also shot some video explaining how things work.

Ordinary "open circuit" scuba delivers compressed air or Nitrox (a blended gas containing more oxygen and less nitrogen than ordinary air) from a tank to a regulator to your lungs. When you inhale, you get fresh air from the tank. When you exhale, the gas -- now containing less oxygen than before, plus carbon dioxide produced by your body -- bubbles out into the water.

Open circuit scuba equipment is robust, reliable, and inexpensive. But it has some significant disadvantages. First, most of the oxygen is wasted. Inhaled air is about 21% oxygen. When you exhale, it's still about 15-16% oxygen, but all that oxygen is blown out into the ocean. Second, those bubbles are noisy, scaring fish and reminding you with every breath that you're using an artificial system. (Military divers also don't like it that the bubbles can be conspicuous when they'd rather not be noticed).

LINK

[DiverDown]

Oops, Looks like I posted a link from the same article as Calvin..