Nitrox Certification!

I took the Enriched Diver PADI course at Sport Chalet.  The course orientation was last week, when we filled out forms and decided when to meet this week (we'd met tonight, Tuesday, one week after the orientation).  In class tonight, we went over the Knowledge Reviews at the end of the course book before taking the exam.  I was surprised that the exam did not contain any calculations, as I had been worried about remembering formulae for calculating things like Partial Pressures of breathing gas components and allowable bottom times.  Nitrox is made up of Nitrogen and Oxygen, in varying proportions, depending on the application.  If one wants to dive for a long time at a fairly shallow depth, then one can boost the oxygen level and reduce the nitrogen so that there is less risk of nitrogen narcosis, though this introduces the possibility of oxygen toxicity, which can be easily fatal as it causes convulsions that cause the diver to spit out their regulator and drown.  What I hadn't known until this class was that although there are some possible symptoms prior to having a convulsive seizure, it's actually more likely that no symptoms will appear prior to the convulsions.  Hmmm, that's food for thought...

The other thing I hadn't known is that the three-minute safety stop when coming up from a dive deeper than 40 feet is a precaution, not a requirement.  I had asked whether we would still make a safety stop when bringing a convulsing or unconscious diver to the surface.  She answered that although safety stops are preferable, if we're trying to keep another diver from drowning, we can just go right up to the surface to expose their face to air that they can potentially breathe.  I suppose it's better to have the bends on the surface than be dead on the bottom, eh?

After taking the multiple choice exam, we completed some practical exercises with our dive computers and a couple of cylinders containing enriched air mixes.  One tank contained Nitrox with 31 per cent oxygen, and the other contained 27 per cent oxygen.  We practiced filling out the forms that we'll be presented with whenever we get enriched air fills, and practiced programming our computers to calculate the new set of criteria when diving with Nitrox of varying gas proportions.

At the end of the evening, Kathy, the instructor, gave us a photocopied list of local (Southern Californian) dive shops that supply Nitrox.  Sport Chalet is not one of them.  We went behind the desk in the SCUBA section of the store to see the up-to-date inspection certificate that dive shops are required to have in order to provide air fills of any type.  Where Peter and I typically go to get our air fills, they do have Nitrox.  Whenever I go to get a fill, the fellow who is there most of the time asks me, "Air or Nitrox?"  and I always answer, "Just air."  Depending on what we decide to dive with this weekend, I might have the opportunity to ask for a Nitrox fill, and present my (temporary) certification card with Kathy's signature.  My permanent card will come in the mail in several days or a couple weeks.

Yay!