According to DAN, equipment problems are the trigger for 15% of scuba diving fatalities, but the problems that cause these tragic end results almost always boil down to user error citing, "improper use, failure to ensure correct configuration, lack of maintenance and insufficient familiarity with the equipment." The best way to learn about your gear and all of its features and functions is to practice with it. But with one piece of dive gear, practice doesn't necessarily make perfect.

When it comes to dive computers, you have to read the manual.

While normal dive data like depth and no-deco times are easy to grasp on any computer, when things get dicey, you need to know exactly what your computer is telling you. For example, among the computers in ScubaLab's latest dive computer review, there is a wide range among warnings displayed and actions taken for missed deco stops. Some give a missed deco warning for five minutes before locking out, others for two minutes, or three. Once in violation mode, displays vary widely; the screen on the computers we tested varies among “VIO,” “VIOLATION,” “SOS,” “Er” or “EEEE.” Some lock out all features when in violation, other than depth or time, while others continue to provide most or all dive data.

There are well-documented instances of divers who got into serious trouble because they didn’t know what their computers were telling them. A thorough read of a computer’s manual is the only way to know how to operate it safely in all conditions, and also to get the full benefit of the features it offers. All of the computers in our test have manuals that are readily available online; examining them before purchase is also a great resource to select the computer that’s the best fit for you.