Waterproof or not ?

[atimegoneby]

I've just had one of those pop up ads appear on my screen for a Seiko 5 green dial model snk805k2 special price £55.99, on Amazon

reading through the garb it says waterproof to 30 metres/98.7 feet then goes on to say not suitable for swimming, snorkelling, water related work, etc ???

just wondered which is right 

[ro63rto]

only good for getting rained on and maybe washing your hands.

Anything less than 100m i take mine off when i go near water.

[bobm12]

Absolutely, and don't shower with it or any other watch, soap and warm water are no good on them. As for water sports/work, some instantaneous pressures are created when we move our hands in the water. Those exceed the 30 m rating (3 ATM ?).

[parmenion31]

i know many people going for swimming wearing their seiko 5 automatic , they havent problems but i dont recomend the watch for sea activity .

[JohnR725]

Waterproof is an interesting term and I was under the impression it was largely abolished replaced with Water Resistant. But googling I see that is still being used? The reason why it was supposed to be abolished is waterproof implies an absolute which is basically almost impossible.

So a couple links Casio has a nice chart showing the varying degrees of water resistance. Another link explaining some of the standards.

Then there's another problem with water resistant watches not often mentioned. Specifically time and temperature changes especially if you can repeat this on a continuous basis. So if you can heat the watch up like hot shower for instance hot tub the air inside will expand a very small amount. The watches designed for external pressure not necessarily internal pressure. Problem with temperature change is the air will expand in the watch when it's warm attempt to return to its normal volume when it cools down with time that repeated pressure vacuum even it's a very tiny amount will slowly pull water past the gaskets.

http://www.casio-intl.com/asia/en/wat/water_resistance/

https://en.wikipedia.org/wiki/Water_Resistant_mark