As I pack to get ready for my Scuba certification dives this weekend, I cannot help but reflect on the amount of science that goes into scuba diving. In fact, without science, a lot more divers would be seriously injured.

So here is a reflection on various aspects of science in Scuba….

Excited for Scuba! Photo Credit: SteelCityHobbies via Flickr
Excited for Scuba! Photo Credit: SteelCityHobbies via Flickr

  • Thank Goodness for Buoyancy- Scuba gear is heavy. Invariably before my confined water dives, I’d help my partner into her gear, she’d help me into mine and I would end up bent over the weight. On top of that, I strap on a weight belt and I can’t help thinking that I’ll sink to the bottom. Once in the pool, I would end up light as a feather. Upon my exit, I marvel on how my gear is so heavy my feet feel pressed into the floor. We also work hard to establish neutral buoyancy. Its kinda fun to sit crosslegged in the middle of a water column.
  • Pressure- The first time we talked about the forces exerted on your body,’Under Pressure’ by David Bowie and Queen popped into my head. Indeed, diving to a depth of just 33 ft adds an entire other atmosphere of pressure. Down around 100 ft there are 4 atmospheres of pressure, so diving cause us to really be ‘under pressure’. So always remember to equalize the air spaces in your body.
  • Pressure 2- I find it slightly reassuring that if you have to perform a Controlled Emergency Swimming Ascent (CESA) in a out-0f-air situation, the air in your lungs will expand as you rise to the surface. This way you actually end up with more air even as your exhaling. Of course, I’d rather never run out of air. I get to test my belief in science while performing a mock CESA during my certification dives. Fortunately, if I forget, and inhale against my regulator, there will actually be air in my tank.
  • Add a bit of Oceanography- Its incredibly important for divers to know about surges, undertows and currents. Think about it. One puny little human with false flippers and strapped on air is powerless against the might of wave action. So we learn to find clues. ‘Waves break in water only slightly deeper than their height, so watching the surf tells you something about the depth.’ We avoid diving from beeches with steep shorelines unless its a mild surf to avoid strong backrush. We watch for riptides, the ‘line of turbid foamy water moving away from shore.’ And of course, you plan your dives based on tides for the best conditions.

  • Fun With Nitrogen- Nitrogen, nitrogen, nitrogen. At extreme depths it can make you really silly due to nitrogen narcosis. It is very similar to heavy intoxication. Watch out if your buddy tries to hand the regulator off to fish, or starts to act like a dinosaur (the famous example of an affected student given by our dive instructor). If you’re underwater, foolish behavior is not really wanted….
  • Less Fun with Nitrogen-We all deal with another aspect of nitrogen too. When the pressure increases on a descent, nitrogen from the air dissolves into the tissues of the body. Which is all fine and dandy. Until you ascend. The excess nitrogen should just dissolve out and the body disposes of it. However, there are limits. If you have too much nitrogen, the body can’t get rid of it at the same speed that it dissolves out. Nitrogen bubbles form in blood vessels and tissues. Its like carbonating soda. In your body. This is the famous bends, or more accurately, decompression sickness (DCS). This is why no one ascends faster than a 60ft per minute, or a foot per second (think about it, one one thousand, two one thousand…). We also use dive tables so we don’t spend too long at depth and absorb too much nitrogen.
  • Math?- About thos
    The front of my RDP
    The front of my RDP
    e tables… The RDP or Recreational Dive Planner makes it ‘easy’ to plan a dive and stay within limits. It accounts for surface intervals between dives (letting nitrogen dissolve away), and for multiple dives. As recreational divers, we plan all dives to be no-decompression dives. Any explanation I try to give regarding how to use it would not be effective. If you’re curious, visit http://www.scubadiver.cc/padirdp.htm.
  • More Oceanography- A brief mention about the thermocline. Is it fair that there is such a huge boundary? One minute you might be just peachy warm, and the next minute you hit another layer of water that is much colder.
  • My favorite, Marine Biology!- They tell us the typical aquatic animal will probably just say “Swim away! Swim away!” I had the image of Finding Nemo at this point… of course. In fact, Nemo was mentioned various times. We’ve learned how to recognize stinging jellyfish and why you shouldn’t pick up a jellyfish and then rub your eyes. We’ve been warned against the
    approaching the blocks of Styrofoam that don’t float, o
    Dogfish are not to be worried about. Photo Credit: David Reece via Flickr
    Dogfish are not to be worried about. Photo Credit: David Reece via Flickr
    r else a ling cod male will charge, protecting the eggs. We’ve also learned the kelp entanglement happens. We’ve also learned ‘defensive measures’. We were discussing dive knives. One of our instructors jokingly told us that the real use of the dive knife was in case of a shark approach. Quickly slice your partner and swim away. Hastily he assured us he was joking. Sharks aren’t really bloodthirsty killers anyway and we’re most likely to see Dogfish (a species of shark). Believe me, I’m not that worried. I’ve dissected a dogfish and they fit on a tray.

Well, thats an overview of science. I guess I should get back to packing for the trip. If I’m lucky, maybe I’ll see one of those darn Pisasters!

My gear is ready!
My gear is ready!

Look forward to interesting posts regarding the Certification Dives.