Dive watch needed
Dive watch check during safety stop

Credit: Stubblefield

What is a dive watch, and should you get one? We answer your questions.

As a dive instructor, I am often asked questions regarding equipment purchase.

And one topic I get a lot of questions about, are dive watches.

So I’ve put together the most common questions I’ve heard over the years here, along with the answers.

Consider it you dive watch cheat sheet.

What is a dive watch?

A dive watch is essentially just a watch that is waterproof enough to withstand the pressure at the depths that divers dive to. A dive watch was an essential tool in the early years of the sport, as they were the only way to measure bottom time, and with that, know when to resurface, and how long of a surface interval was required before the next dive.

I have a watch that says “waterproof”, can I use that for diving?

Maybe, but check you manual first. Watch manufacturers operate with a scale of waterproofness, from splashproof (you can wear it out in the rain, or do the dishes wearing it) to watches that can withstand the pressure thousands of feet below the surface. Look for the depth rating, and go for at least 100 meters/300 feet. While you’ll probably never dive this deep, you’ll want the safety margin to keep the watch safe.

Do I need a dive watch with dive computers everywhere?

Honestly, no. A modern dive computer tells you not only the time, the dive time, and the depth, it also gives you remaining time at depth (how long you can stay at your current depth before needing to resurface), and it can calculate your surface interval for you. So from a practical point of view, dive watches are obsolete.

So What’s The First Dive Equipment You Need To Purchase?

Dive computer better than dive watch

A dive computer is a very practical substitute to a dive watch - Credit: Nart

Then why do many divers wear them?

Partly, tradition and preference. Dive watches are still strongly associated with the sport, and many divers wear them because they like them, and because they like having a backup for their computer, even if this backup doesn’t have all the features of the computer. Some dive watches feature depth gauges, and these can actually work as a rudimentary dive computer backup, allowing you to do a complete ascent to the surface, including any deco or safety stops along the way. But many divers, and non-divers, do simply wear them because they like them.

Why do dive watches have that rotating thingy?

That rotating thingy is called a rotating bezel. It is marked with minutes up to 60 minutes (typically) to allow divers to quickly discern how long they’ve been down. You rotate the bezel so the zero mark is at the minute hand when you descend, and then you can read the duration of your dive at any time, without having to calculate it. And the bezel typically only rotates one way, so if it is accidentally moved, it will only shorten your dive, not extend it, possibly beyond your no-decompression limit. Always err on the side of caution.

Do you know Why Diving Should Be Done Slowly?

Dive watch bezel mark up to 60

A watch marked up to 60 Credit: Public Domain

What should I look for in a dive watch?

First and foremost, depth rating. At least 100 meters/300 feet/10 ATM. Then of course, a rotating bezel. Material is worth considering as well, stainless is good, titanium is better. Titanium is lighter and more corrosion resistant. Whether you choose a rubber strap or a metal bracelet is a matter of preference, but make sure that both are long enough to allow you to wear the watch over your wetsuit or drysuit. Most metal bracelets will have an extension function to ensure this. A depth gauge is useful, too. Also, make sure the watch face is clean enough to be easily legible.

You may hear wild stories about an exotic feature called a helium valve. Don’t get hung up on this. A helium valve is useful for commercial divers doing very deep saturation diving, where they live in underwater habitats filled with a trimix breathing gas containing helium. The helium molecules, being extremely small, can make their way into the watch case, and then, when the diver ascends, these molecules expand (due to dropping pressure) and can damage the watch.

Titanium dive watch

A titanium dive watch is lighter and more corrosion resistant - Credit: diveintowatches.com

Here's more about Deep Diving: Rules, Recommendations And Fun Facts

But for recreational divers, even technical ones, this isn’t an issue, as we typically do not spend a lot of time in underwater habitats hundreds of meters below the surface.