How to Read Recreational Dive Planners on a Computer

SCUBA is fun, but you must be safe.

A dive computer offers the recreational diver the ability to maximize the length and depth of her dives without the burden of having to use dive tables to calculate nitrogen levels in the body tissue. Using a dive computer is not only convenient but safe, customizing its calculations to the exact times you spend at certain depths.

Things You'll Need

• Dive computer

Instructions

1. Turn the dive computer on. Some dive computers have a button on the side or front, but many are simply activated by water, which makes it easy, since the computer will automatically activate once you get into the water.

2. Check the battery reading. According to SCUBA certification agency PADI, many dive computers will need to run 24 hours or longer to calculate changes in dissolved nitrogen. This means that if the "low battery" warning is blinking, you need to change the battery.

3. Check the depth reading. Because depth is the most important component in calculating nitrogen absorption rates, it is usually displayed fairly prominently in the center of the screen. Some computers may allow you to toggle between meters and feet, so choose the system with which you are most comfortable.

   When you are at the surface, the computer should read zero. If it does not, you will need to re-calibrate the machine, because all of the other depths will be off.

4. Begin the descent. As you descend, the computer will begin reading depth. Be sure not to exceed the planned depth.

5. Monitor the "no-stop" time. This is the time that you are able to remain at the given depth without having to do a decompression stop. Recreational divers should not be doing dives that require decompression stops, according to PADI standards, so this is the time by which you should abide. Plan to begin the ascent with time to spare on the clock.

6. Monitor the temperature and other features. Though the above components are the essential parts of any computerized dive planner, some computers will also display the water temperature, as well as show compass readings. You may even be able to toggle to have the computer monitor dives with a NitrOx algorithm. NitrOx is an air mixture that has a greater oxygen-to-nitrogen ratio, which allows divers to enjoy longer dives.

7. Watch the depth monitor as you ascend. Most dive computers have an integrated alarm that will warn the diver with a beeping sound if the ascent is too quick. If you have stayed down for too long, the computer will also beep and indicate the need for a decompression stop.

8. Read the dive profile once you surface. This will show the interval, in minutes, that you must wait before diving again to avoid injury. It will also display the maximum depth you are allowed to reach on the next dive. Some computers may also display the amount of no-dive time before you can fly in an airplane.

Tips & Warnings

• Always have dive tables on hand even if you do have a dive computer. If, for some reason, the computer malfunctions, you will need to rely on the tables to calculate your diver's profile.

References

• PADI: Dive computers