PUERTO RICO — Dive Computers or Dive Tables? That is the question… No need to think too much about the most popular and probably best answer: Dive Computer. Yes, a Dive Computers will make your diver-life much easier; it eliminates much of the time you need to plan a dive, its algorithm allows you to get more out of your dives, more bottom time and less surface time between immersions (Surface Intervals). They come with all sorts of different, convenient features, and depending on the model and price range there are an incredible array of options to choose from: you have the very basic computers, and others with different settings like Enriched Air or “EANx,”some that automatically adjust for altitude, type of water, etc. Some are more conservative than others, and some you can adjust the algorithm to be more or less conservative. All new computers will measure your depth and time underwater and quite a few other variables with greater precision than old fashioned tables and analog gauges. However, no matter what you choose as your dive computer remember: Always read the manual before use!
Now, that I sound completely on the side of Dive Computers let me tell you why you should understand and use Dive Tables. Why have the tables become so unpopular? Well, because of computers, obviously! But do you know that tech divers use dive tables along with carrying more than one computer? Why would they do that?
Because even the best of computers can fail. The most simple recreational dive can go wrong and the types of deep and complex dives inherent to the tech diving world have added risks of their own, they’re deep! They’re complicated! More pressure, more risk! Dive equipment is made to last, but nothing is perfect and the more complicated the dive the more that can go wrong. But this is why I would argue that even recreational divers who never plan to go very deep or penetrate caves or wrecks should still pay what amounts to professional attention to their knowledge and equipment. I don’t mean that every recreational diver should sport two (or three) computers, four cutting devices, and carry a canister light with two backups–rather to approach one’s own training and gear with a serious eye. Scuba diving is great fun but it does carry some inherent risks: risks that can largely be mitigated by good training and proper knowledge.
As a professional diving instructor I’ve learned not to continue a dive with only the Table if the computer fails. If your computer fails you should end that dive. However, you can definitely use Dive Tables for the rest of the days you’ll be diving. Also Dive Tables or RDP/eRDPml are great to understand and make use of, if your computer is not built with EANx and, or Altitude settings. No matter what you choose, you have to learn to read (and understand) both: your Computer(s) and the Table(s).
Recently I took the Altitude Diver Specialty in Lake Atitlán in Guatemala with ATi Divers (big shout out to the only dive shop around the lake and my Instructor Daniel who is an RDP genius)! Being a “sea-level” Caribbean, shallow-water instructor myself, I had pretty much put the Tables in a trash can until the day I had to learn to read the RDP Table in a theoretical manner for the Altitude Specialty. It fascinated me and finally I can say I understand them and their importance. In conclusion, exercising your mind and keeping it at work should never be a thing of the past!
ABOUT THE AUTHOR — I recently met Christina Lorenzo at La Iguana Perdida in Santa Cruz la Laguna, Guatemala where she was working on her Altitude Specialty. Christina, who is currently back in Mexico working on her Master Scuba Diver Trainer rating, wrote the following article as something of a companion piece to my last article on dive watches following discussions we had on diving and, ideally, how one should train. Christina is one of those restless, polymath adventurers you seem to meet at places like Lake Atitlan. Based out of Rincon and Aguadilla Puerto Rico, she ran track and field in college, was part of the national Roller Derby team, traveled to Dallas for the Roller Derby World Cup, established herself as a hairdresser with a specialty in colorimetry, and discovered scuba diving through her clients. She decided to go for dive certification in Mexico close to the cenotes she’d been wanting to see for years. The pandemic lock-downs were starting and she booked the very last flight from the closest airport before travel was shut down for over a year. “That was the best decision of my entire existence,” she told me, adding, “I met Xibalba through the cenotes, did my Rescue Diver course with a local crocodile, dived the second largest coral reef in the planet, and wrecks, and caverns… I became a Divemaster and finally an Open Water Scuba Instructor. On a recent trip to Guatemala’s Atitlán Lake, I found a place where you can feel inspired again, it made me realize I could take my diving farther than just Open Water Scuba Instructor. Life is too brief to just dream about what one could have achieved.”