You would have to be crazy to dive in the North Atlantic ( or anywhere ) and not protect yourself with inexpensive accident insurance coverage available from DAN - Diver's Alert Network. Check your existing health insurance policy, and you will most certainly find that accidents involving scuba diving are excluded ( skydiving too ).
DAN offers various packages, tailored to everyone from the most occasional Caribbean diver to the hard-core Andrea Doria techie. Coverage includes recompression chambers, transport, and other costs, both in and out of the country. The yearly fee for all this is not much more than the cost of a mask, or a single day's boat diving, and also includes membership in the organization and a subscription to their excellent safety-oriented magazine Alert Diver.
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