Posted by MHK on October 02, 2000 at 15:25:00:
In Reply to: Octopus on scuba rigs posted by isidoros on October 02, 2000 at 08:51:25:
It has the express purpose that your open water instructor taught you in your open water class. Moreover, I assume you used it in your class and should therefore know the reason...
If you are NOT a diver and this question is for some research paper, the down and dirty answer is that it provides an alternative air source in the event of an out of air situation. I caveat that answer by saying there is more to scuba diving than knowing the answer to that question.
So, in short, if you are a diver you should know better..
Later