We all know what a helium release valve is, right? That weird, circular fitting on the side of some dive watch cases, usually at nine o’clock, sometimes ten o’clock. All the best dive watches have them. That’s how you know you’ve got a genuine, gnarly tool on your wrist. Right?
Well, not so fast.
The Rolex Sea Dweller is equipped with the Helium release valve.
Helium Release Valve
It turns out that helium release valves, or helium valves, may actually be a liability in a dive watch, rather than a benefit. To learn why that might be, let’s take a look at the He valve (He is the element symbol for helium – sometimes marked on crown-style valves like the Omega Seamaster Planet Ocean). What is it? What does it do? How does it work, and why might a diver need it?
This feature is typically found on a dive watch. We will take the modern Rolex Sea-Dweller for example.
First, you need to know that a helium molecule is extremely small – among the smallest of molecules. Under the right circumstances (like high pressure), helium can sneak past the seals of a watch where water molecules or the molecules of other gases that make up our air can’t.
The Helium Release Valve on the Sea-Dweller allows the watch to decompress.
So helium can build up in a watch under external pressure, until that external pressure is released. That’s when the built-up helium, which has now pressurized the watch case, may well blow the crystal off the watch. Not fun. That kind of thing will take your eye out.
To prevent such an occurrence, a helium release valve automatically depressurizes the watch when it returns to a sea level pressure environment. It’s a one-way valve so it only lets pressure out of the watch. It’s designed to never allow water – with its larger molecule – to pass into the watch. (If helium gets in by that route, it’s OK – the valve’s whole purpose is to let helium out. Back out, so to speak.)
This feature was first added on the Double Red Sea-Dweller, but Rolex decideded to continually advance their technology.
But wait! Why the heck would helium get into the watch in the first place.
Well, in order to counter the effects of nitrogen in the air breathed by workers (likely divers) temporarily living in deep water habitats, that nitrogen is largely replaced by helium. And the local pressure in these habitats is typically higher than sea level atmospheric pressure.
So that’s how helium gets into divers’ watches. It’s driven in by that increased pressure while divers are residing in their living quarters at depth. And when they finally come back to the surface and decompress after days or weeks at depth (and increased pressure), their watches are liable to explosively pop their crystals if that helium build-up isn’t properly released.
But by that explanation, you can see that the valve doesn’t have anything to do with actual diving. Instead, it has to do with living in a pressurized environment when not diving.
Sea-Dweller 1665 “Great White” Caseback it is written “Rolex Oyster Patent Gas Escape Valve”
That’s why a very specialized professional/ commercial diver might need a watch with a helium escape valve. Conversely, if a diver is not living in a pressurized habitat for days or weeks, they have no need for a watch equipped with a helium valve.
And that’s where such a valve’s potential liability comes in. As a diver friend and watch writing associate of mine once said, we’re a little squeamish with any extra holes in the cases of our dive watches.
If the valve should fail for any reason, the watch can flood.
The truth is they represent an additional failure point – a potential leak path. If the valve should fail for any reason, the watch can flood, effectively leaving the wearer with a broken tool. In days of yore, this could be a deadly dangerous situation to be in. Now? It only represents an expensive repair bill.
So why are brands putting helium valves in so many dive watches?
As you can imagine, most folks who have an opinion think the answer is marketing. Helium valves are cool. They just seem like they belong on a dive watch, as if the watch is less of a tool if the valve is not there. So their presence helps sell the watch.
And let’s be honest. With the availability of modern dive computers, the dive watch as a vital dive tool is an anachronism. Any liability we writers can conjure up is on paper only, because the vast majority of divers operate in the cube farms of Corporate America, not the kelp beds of the continental shelf.