Seiko & Citizen Watch Forum Message Archive

when enough of it gets in at depth (and under high outside pressure) it can actually cause the crystal to pop out or break when the the watch is returned to sea level (low outside pressure).

There are two ways to deal with this. The Swiss have gone the route of the helium escape valve, which simply acts as a spring-loaded one-way vent to allow the gas to escape once it gets in. Only the amount of helium that is under pressure is released...there will still be some helium in the watch.

Seiko went the other way, and designed the watch to only allow an INSIGNIFICANT (read harmless) amount of helium to enter the watch in the first place. There is nothing special about the material used to make the gasket, it is just designed to fit with the crystal and case in such a way as to allow only a minimal amount of helium to enter. Plus, the one-piece design of the case eliminates the likely cause for most helium incursion...the caseback gasket. While the watch is not "helium proof" in the literal sense of the phrase, it is basically immune to the effects of helium damage. The amount of helium that can enter is so small that it cannot cause problems. But like the Swiss design, there will always be some residual helium in the watch. It's just that simple, guys. Regards, Aaron

"I don't like stuff that sucks." - Butt-head