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Welcome to Dive Gear Reviews, a comprehensive guide to scuba diving equipment. Scuba diving is an expensive pursuit, so looking up reviews for a particular article of equipment is a wise precaution before investing any hard-earned money in it. However, consumer reviews may or may not be written by an experienced diver, and magazine reviews could be suspect due to the advertising ties of the publication in question. Dive Gear Reviews provides cross-referenced reviews assembled by an expert, making it possible to see at a glance what multiple sources said about a particular piece of scuba equipment. If one magazine loved a scuba regulator or a dive computer, but the consumers hated it, that information will be found here.
03
October

Dive Computer Algorithms

Written by Dive Gear Reviews Editor. Comments Off on Dive Computer Algorithms Posted in: Dive Computers, Dive Gear Tips, Scuba Product Guides
Suunto Dive Computer

A Suunto wristwatch-style dive computer
(Credit: Wikimedia Commons)

A dive computer’s algorithm is at the heart of what that particular gadget does, because when you get right down to it, everything else on the computer is an accessory. Yes, the depth gauge replaces or supplements the old analog depth gauge, but a dive computer is first and foremost about increasing your margin of safety and liberating you from pesky dive tables. Just like PADI’s familiar dive table, dive computers base their conclusions on formulaic calculations, and these are driven by the algorithm. Having a basic understanding of what the algorithm is and it’s key role in the functioning of your dive computer is therefore a critical piece of information when shopping for a new number cruncher.

Unless you have an advanced degree in mathematics, analyzing any of the several dive computer algorithms out there directly isn’t possible, but thankfully you don’t need to. Reviewers always speak of dive computer predictions as either “conservative” or “liberal.” A conservative algorithm is one that takes a tight view on predicting your nitrogen load, giving a larger margin of safety against decompression sickness while curtailing bottom time. Liberal algorithms make more expansive predictions regarding nitrogen load, which increases your dive time while cutting into the safety margin.

An important thing to remember about the nitrogen load predictions made by dive tables and computers alike is that they are based on models, and those models are generalized. The human variable ensures that it is impossible to know where the exact safety line is for each person. Many higher-end dive computers now have features that allow the user to dial the safety margin on the algorithm up or down to suit their needs.

So, how algorithms work in practice depends a great deal on your health, your past experience, and your typical diving schedule. A diver who has gone deep plenty of times, operates safely, has a light dive schedule that day, and has never suffered even the slightest joint ache might want to dial the safety margin on their algorithm all the way up, and if that describes said diver’s typical diving pattern, she might want a computer with a liberal algorithm in the first place. On the other hand, divers who get wet three or four times a day every Saturday and Sunday and sometimes get a little achy at the end of the day should go conservative.