hi , i had the same question some time ago , after some researchi found this :
The International Organization for Standardization issued a standard for water resistant watches which also prohibits the term waterproof to be used with watches, which many countries have adopted. In order to pass for this certification it is not required for each and every individual watch to be subjected to tests, only lot sampling is required.This standard was only designed for watches intended for ordinary daily use during exercises under water for a short period under conditions where water pressure and temperature vary. The tests are:
Immersion of the watch in 10 cm of water for 1 hour.
Immersion of the watch in 10 cm of water with a force of 5 Newton perpendicular to the crown and pusher buttons (if any) for 10 minutes.
Immersion of the watch in 10 cm of water at the following temperatures for 5 minutes each, 40°C(104F), 20°C (68F)and 40°C(104F) again, with the transition between temperatures not to exceed 5 minutes. No evidence of water intrusion or condensation is allowed.
Immersion of the watch in a suitable pressure vessel and subjecting it to the rated pressure for 1 hour. No evidence of water intrusion or condensation is allowed.
Exposing the watch to an overpressure of 2 bar, no more than 50µg/min of air is allowed to get inside the case.
No magnetic or shock resistance properties are required.
No negative pressure test is required.
No strap attachment test is required.
No corrosion test is required.
So in short it means that the minimum requirement is that the watch will pass a 20 meter(66') test. However if the watch have a different rating then just plain Water resistant for instance a 30M, 50M,100M,200M etc rating then it needs to be tested in a a pressure chamber with a static overpressure equvivalent to the pressure at that depth.
The last part was the most important , so the Core has indeed a ISO 2281 certificate but with a extra added 30m/100ft guarantee, wich makes it safe for shallow to medium dives , also the Core has something called stinger buttons wich can be pressed underwater.
Anyway i've been swimming with my Glacier Gray for some time now and no problems ocurred, hope this helped , cheers
answered 2 years, 10 months ago
1out of 1found this answer helpful.
The Core has been designed so that it can be taken to a maximum depth of 10 meters / 30 feet.
answered 4 years ago
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