When scuba divers ascend too quickly, they risk getting Decompression Sickness (DCS), commonly known as "the bends." Because scuba divers breathe compressed air at depth, nitrogen builds up in their tissues. If they come up too fast, that nitrogen forms dangerous bubbles in their blood.
For decades, scientists believed that because freedivers only hold a single breath of air at the surface, they didn't absorb enough nitrogen to get DCS.
They were wrong. Enter Taravana.
What is Taravana?
"Taravana" is a Polynesian word that roughly translates to "to fall crazily." Long before modern freediving existed, the pearl divers of the Tuamotu Archipelago in French Polynesia were diving to 30 or 40 meters, over and over again, for 6 hours a day.
Observers noticed that after years of diving, many of these pearl divers began showing severe neurological symptoms: paralysis, vertigo, hallucinations, and sometimes death. They called it Taravana.
In the modern era, doctors recognized Taravana as a form of decompression sickness caused by repeated deep breath-hold dives.
How Does a Freediver Get the Bends?
Even though you are only taking one breath of air at the surface, that air still contains 78% nitrogen. When you dive deep, the pressure compresses your lungs, forcing some of that nitrogen into your bloodstream and tissues.
If you do just one deep dive and come back up, you are perfectly fine. The small amount of nitrogen safely dissolves back into your lungs and is exhaled.
The danger occurs when you do repeated deep dives with very short surface intervals. If you dive to 40 meters, surface for only 30 seconds, and immediately dive back to 40 meters, your body doesn't have time to off-gas the nitrogen from the first dive. Over a 2-hour session, that nitrogen accumulates, eventually reaching critical levels and forming bubbles.
How to Prevent Taravana
Fortunately, Taravana is incredibly easy to prevent if you follow basic freediving safety protocols. The golden rule of freediving is managing your surface intervals.
You must give your body enough time at the surface to off-gas accumulated nitrogen before you dive again.
The standard rules for surface intervals:
- For dives shallower than 40 meters: Your surface interval must be at least 3 times the duration of your dive. (If your dive took 1 minute, you must rest at the surface for at least 3 minutes).
- For dives deeper than 40 meters: Your surface interval should be your depth divided by 5, in minutes. (If you dive to 50 meters, you must rest for 10 minutes).
- For extreme dives (80m+): Only one max-depth dive per day.
At our school, we rigorously enforce surface intervals during our Wave 2 and Wave 3 courses. Your instructor will always act as your timekeeper, ensuring you rest completely before your next descent.
Dive deep, but dive safe!