The Dive Watch Bezel
The dive watch bezel is the signature characteristic of the watch. This simple yet significant feature first appeared on dive watches out of necessity. When scuba diving grew in popularity as a sport in the 1950’s, the dive watch was an indispensable tool. The bezel in particular allowed divers to track their elapsed time under water. This feature was so important, it made its way into the International Organization for Standardization (ISO) requirements. These govern what defines a dive watch.
As the dive watch evolved, so did the bezel. Watchmakers began looking to solve additional problems for divers to make diving safer. Soon, bezels began incorporating ways for divers to track more than overall immersion time. They could calculate no-decompression times and decompression stops long before modern digital dive computers were developed.
If you’ve ever looked closely at a dive watch bezel, you know it typically features a combination of stick markers and numbers. It can seem mindboggling as to how these markings allow all these intricate and important calculations. To understand them, let’s first look briefly at the process divers follow for decompression.
What is Decompression?
In the simplest terms, every depth has a maximum time divers can tolerate before they have to pause on the way to the surface to decompress. Divers must take breaks at certain depths on the way back to the surface once they exceed this “no-decompression limit.” They must take these particular breaks while their respiration clears the tissues of the excess nitrogen that builds up at great depths. If they don’t follow this process, they can get “the bends.”
The design intention of the most basic form of a dive watch bezel is use with the set of tables that indicate the no-decompression limits for each depth. To use the bezel, the diver sets the zero mark (which often appears as a luminous arrow) opposite the minute hand. As dive time elapses, it shows on the bezel.
DOXA and the “No-Decompression” Bezel
In 1967, Doxa patented a special “no-decompression” bezel. It features a double scale with the no-decompression limits engraved on the outer ring, eliminating the need for a table. Using this bezel begins in the same fashion—the diver sets the zero mark to the minute hand. As the diver descends, the additional scale indicates when to surface for depths from 60 to 190 feet.
Today, digital dive computers are oftentimes used in place of analog watches. Still, the dive watch hasn’t lost its trademark bezel. They continue to evolve, improve, and take on a number of forms, though they’re not as frequently used for their original purpose.