Scuba diving is a very technical sport and having the right equipment is essential. There are lots of items of kit required if you want to dive reefs and wrecks, not least an oxygen supply, but aside from some means of breathing underwater, a dive watch should be very high on your list of must-have pieces of kit for scuba diving.
What Special Features Does A Dive Watch Have?
First and foremost, a dive watch needs to be water resistant. In order to qualify for the minimum ISO 6425 standard, a dive watch must be water resistant to at least 100m (you can expect better quality watches to be water resistant up to at least 300m). Dive watches must also be resistant to water pressure, which increases the deeper you dive and to guard against water ingress, really good quality dive watches have screwed down crowns to create a tighter seal. You also need to be able to see the minute hands on a dive watch clearly, so a good dive watch will have a luminous dial and clearly visible hands if it is not digital.
Why is a Dive Watch So Important?
A dive watch is not essential, but it is very useful and can make the difference between a safe dive and a disastrous one. Dive watches are designed to give you essential information while you are underwater: typically how long you have been down and therefore how much longer your air supply is likely to last. You could of course take a guess on these things, but that would hardly be very sensible, particularly if you are diving at any great depth.
Why is Gauging Remaining the Air Supply So Vital?
When the air runs out, you need to ascend to the surface in order to breathe and if you are several hundred meters below, you are likely to be unconscious before you ever get there. However, you will also want to make the most of the time you do have underwater, exploring reefs, taking pictures of amazing aquatic marine life and testing your skills diving through a wreck, so heading up to the surface too soon is not ideal. With this in mind, a dive watch can tell you exactly how long you have been underwater and how long you have left before you need to head back up to the surface.
Using a Dive Watch to Calculate the Elapsed Dive Time
Some dive watches can calculate the elapsed time automatically as soon as a diver starts to descend but not all of them do this. For other dive watches, the bezel is normally twisted at the beginning of a dive so that the arrow is aligned with the minute hand of the watch. As the dive progresses, the diver keeps a close eye on how far the minute hand of his dive watch has moved away from the bezel marker, which tells him exactly what the elapsed dive time is.
The bezel on a dive watch is the key to calculating elapsed dive time, but unlike other watches, the bezel on a dive watch can only be twisted anti-clockwise. In case you are wondering, there is a very good reason for this. Because the bezel can only move in one direction, this eliminates the possibility of accidentally extending the dive time and leaving the diver with no air supply. If the bezel is inadvertently knocked on a dive watch, the dive time would be decreased rather than increased, which would be an inconvenience but certainly not life threatening.
How Do I Know if a Dive Watch is Suitable for the Purpose?
All dive watches are manufactured in accordance with ISO 6425, which means they are subjected to rigorous testing before being sold as dive watches. Watches suitable for diving are designated as “divers” watches, which distinguishes them from inferior watches that are not suitable for the purpose.
What are the Alternatives to Dive Watches?
Dive computers are the sophisticated version of a traditional dive watch, and if you are a serious scuba diver, you may wish to invest in a purpose designed dive computer. Many dive computers are integrated into the air supply, which means the computer is able to track a diver’s air consumption throughout the dive. This helps to eliminate any uncertainties about how long the air supply is going to last under a variety of different diving conditions, which should make the dive a lot safer.
Did you know that it is even possible to buy Rolex watches that are suitable for diving? Ideal for super suave divers, they are sure to be the envy of many!