Helium Release?

[bikemonster]

Hi All

The Omega Seamaster Pro has a helium release valve.

Shamelessly pilfered from the Web:
"This OMEGA innovation is indispensable to divers who must spend several days in a diving-bell. A watch without a helium escape valve could explode from too much pressure inside the case when the diver returns to the surface. By unscrewing the crown positioned @ 10 o'clock, the pressure is released through the valve without water infiltrating the case. "

All very well and lovely, but the question that I have is this: How does helium get into the watch in the first place?

Is it that the guys in the diving bell are breathing a helium-rich atmosphere and the small size of the helium molecules allows them to sneak past the watch seal?

In which case, why does the watch not implode when first exposed to the pressure of the diving bell?

Anyone know?

James

[bikemonster]

So, thanks to the contributors to this thread, I now understand that the helium release valve is only necessary on watches which are used in a DRY submarine environment.

Seems to me that if a person were to be going to spend a great deal of time in a helium-rich, high ambient pressure environment, they would be better off with a completely non water resistant watch, which would allow pressures to equalise.

Or am I missing something?

[bikemonster]

Thanks andy_s.

Now it makes perfick sense. Well from a functional point of view.

It really does seem hugely gimmicky for just about every so-equipped watch sold though, doesn't it? Especially when most of those watches will never go deeper than the bottom of a swimming pool.

James

[bikemonster]

Vipers, by dry submarine environment, I meant an environment that is beneath the surface of the briny but not in the water.

In a wet submarine environment (as in, within a submarine that was full of water), I don't think anybody would be too fussed about the depth rating of their watch, or whether it had a helium release valve!