What is a Dive Watch?

PREFACE: I am not a diver, therefore the information provided on this page should not be used as guidance for actual diving.

A dive watch is a wrist instrument that has a unidirectional bezel that provides divers with an alternative source of elapsed time for the current dive. A suitable dive computer should be the primary source for this information. That said, the dive watch style is very popular among watch aficionados that do not even dive, such as myself. To me it is just like the SUV in the automobile industry. Most owners’ will never take them off-road but love the fact that they can should they choose to. Personally I love the fact that my watch can go places I can only dream of.

Now that we have that established, here are my criteria for a “TOOL” dive watch: (excluding dig. watches)

Must have a unidirectional bezel (bonus if it is lockable, Aquatimer & PloProf)

Bezel must be easily readable at a glance (clear and obvious marker at 0 minutes)

Must be water-resistant to a min. of 200m

Must have a totally waterproof band (preferably SS, nylon or rubber, with an extension)

Must have a high contrasting, none cluttered dial (like the Marathon SAR)

Must have sufficient luminescent coating (it must be legible at all times)

Must have a mat finish (polished surfaces may glint and attract aggressive fish)

Must have a large, easily identifiable minute hand (most important for diving)

Must have a screw-down or lockable crown (lockable like the Panerai Submersible)

A quick note on luminescent paint used on dials. I have been asked many times, which is better, Luminova or Tritium. To be honest, I do not believe one is better than the other, just different, though I prefer Luminova. I find it glows brighter after being charged for only a few seconds. The only problem is that it does not last all night. Here are a couple of great articles on luminescent paint:

Watch Enthusiast's Primer on Phosphorescence By BillHud
Luminous Watch Hands By Bruce Lulu

Another quick note, but this one is from Bob (of Broadarrow.net) on screw-down crowns:

While I prefer a screwdown crown, actually it is the gasket system that is the primary water barrier. The screw down merely keeps the crown and or pushers from being jostled and possibly causing a gasket breach. The (infamous) Navy SEAL Luminox which is advertised as a Dive Watch does NOT have a screw down crown. Nor does the real P650 type 6 that the Luminox copies. Many people have successfully taken their P650's on dives.

*Bob has been a Professional SAR (Search and Rescue) Diver for over 22 years.

I feel it is also important to clarify why a unidirectional elapsed timing bezel is so important. While diving the actual time is irrelevant, what is important is the time remaining for your dive. The elapsed timing bezel is lined up with the minute hand on your watch prior to entry and thus letting you know how much time you have been submerged. If the bezel is bi-directional, a simple knock can dislodge it and cause you to overstay your bottom time beyond no-decompression limits, which can be extremely DANGEROUS. This is also the reason why a dive computer should be your primary source of information.

You will note I did mention the word “TOOL” before listing the above characteristics. What I mean is that the watch’s main intention is to be used as a back-up timing device for real diving. Since many, if not most wearers of luxury Dive Watches are not actual divers, many variations of this theme are acceptable.

Such as polished cases, like the Breitling SuperOcean or even white gold, like the bezel on a few of the Omega Seamaster Professionals. Of course as appalling (to me) as diamonds are on any watch, they can be found on many Dive Watches, for instance this Rolex Submariner.

One major question you must ask yourself before diving with that beloved Blancpain Fifty Fathoms is how much would it bother you if you scratch-up your watch? Keep in mind that in the water you may not feel the occasional bump with a coral reef, nor will you feel your arm rubbing in the silt. Before you know it you look down at your prized possession and voila a BIG gash... (gulp)

In my opinion, best get yourself something like a Suunto dive watch/computer and keep the $$$ dive watch for desktop diving, like me! Then again, what do I know, I don’t dive... yet...

Thanks for reading, ENJOY the site!!!

Marc


ADDITIONAL NOTES:

Bob also had this to add:

1) Most Dive computers are not timing devices per se. That is, they do not have a time of day or timer function. I know there are some exceptions, but the Professional model that I use from Uwatec primarily measures tissue nitrogen absorption and bottom time. It does not tell me what time it is, nor will it allow me to time events.

I find a watch essential to tell me what time it is, and also to time events. This is critical on such occasions when I have had to set and time underwater detonations.

2) The attraction of game fish to shiny watches is quite overrated. Yes, it could happen, but half of my safety gear has flourescent grab handles for easy visibility under emergency situations. In all of the time that I have been diving in the open ocean, I have yet to have been molested by any large fish. Just jellyfish...

3) My own dive watch of preference on particularly nasty dives is the Casio G-Shock. The G-Shock has several non-screw down pushers and yet the gaskets keep the water out. Incidentally, the G-Shock does NOT have a turning bezel.

4) What is a dive watch? A dive watch is a watch that can be worn diving. No offense, but I go with what works. No one (especially someone who doesn't dive) is going to tell me what I can and can't wear underwater. Please do not take offense at that, but I believe that tools should be designed and defined by the folks who use them.

None taken my friend, THANKS FOR YOUR HELP!


Moxie, who is another diver from the DWF, has this to add:

A dive watch is the backup timing device when using a dive computer but is actually the primary when diving with tables. But even when using a computer I like to use my dive watch to track elapsed time on my 5 minute "safety stops."

A computer is actually essential today if you want to maximize your bottom time. Diving with tables assumes a "square" dive profile which assumes you stay at maximum planned depth for the whole dive. You get no credit for the fact that you may spend the bulk of a dive at, say, between 40 and 20 feet after a 3 minute excursion to 80 feet. The tables assume you stayed at 80 feet until you began your ascent. The computer, on the other hand, has an algorithm that takes these variables into account, which translates into spending a lot more time underwater, the point of the exercise, after all.

The newer computers (I have the Oceanic VersaPro nitrox computer, wrist mounted)do in fact tell time (and date) as well as track elapsed time and various "time to go" calculations based on nitrogen and/or oxygen loading, depending on gas mix used. The no decompression time left is the primary of these in recreational diving.

Thanks Moxie!