Progress. The unit is waterproof but only on a flat sea. A sandwich bag could pas the test. Eh? read on...
Thank you for contacting Garmin International.Most Garmin GPS units are waterproof in accordance with IEC 529 IPX7.
IEC 529 is a European system of test specification standards for classifying the degrees of protection provided by the enclosures of electrical equipment. An IPX7 designation means the GPS case can withstand accidental immersion in one meter of still water for up to 30 minutes. However this does not include the unit withstanding moving or rushing water such as a current, wave or hard rain.
Oh, and then the kicker, considering I'd contacted them through the myGarmin site where the unit is registered and filled in my address three times!
I'm sorry however I was not aware that you were in Europe. You will need to contact our European Repair center at the phone # below.
Free 0808 238 0000 (within U.K.)
+44-870-8501242 (outside U.K.)
Some suggestions/warnings for using this unit appear on the UK Forum. I recommend none, and you follow at your own risk!
* Tape over rubber 'seals'
* Smear a tiny amount of vaselene on the terminals
* Always use a dry bag. Unless you feel it's going to 'pressure cook' condensation uinto your unit
* Use new silica gel sachets or some absorbent paper inside to help with condensation
* Rinse in fresh water (obviously, not running water, just dunk in a bucket)
* Dry with rubber plugs out in warm room
Anyone thinking IPX 7 is a good waterproof standard might heed Jim's words:
The IP rating is not explicitly about water resistance but a unit or enclosures ability from preventing things entering it. The X actually means that it has no rating for whether or not solids can enter, strange that this part cannot be determined yet water reistance (the 7) can be? As far as I'm concerned IPX7 is a mickey mouse rating, proper equipment would be IP67 or IP68 rated, like the glands and box I use for my pump electrical system. In fact I think I have an IP69 connector and level 9 doesn't even appear on most lists!
Or as Tom put it:
It is a static test at 1m in fresh water, which adds <1.5>
Edit: I now have a return authorisation number and the unit is on its way to Southampton Special Delivery