Embrittlement in the deep ocean

I am interested in any reply regarding the potential for hydrogen embrittlement on deep (>1000 meters) moored oceanographic arrays with an intended service life of 1-3 years. There is a mixture of vulnerable components which includes:

*galvanized alloy steel and galvanized non-alloy steel connectors
*stainless swivels and pins
*stainless weldments
*stainless screws, nuts, etc.
*grade 30 mechanically galvanized proof-coil chain

The moorings are static after deployment except for the slight deep-ocean current influence.

I'd worry less about embrittlement and more about salt water corrosion on the galvanized stuff. On the stainless, I'll defer to someone else who knows more, but I'd bet that salt water corrosion is still a bigger issue.