Arch, that’s true. However, I would assume that if manual ice removal tools were not deemed sufficient, additional means and systems would have been retrofitted when the vessel was prepared for Shell’s charter off Alaska, a service where icing is probably a bigger problem than in escort icebreaking duty in the Northern Baltic Sea.
I quickly skimmed through DNV’s rules for DEICE notation. As with most recent rules, there isn’t much in it and “arrangements and methods for anti-icing and deicing will be considered for approval in each case”. How I understood that is something like “we don’t really know what is needed, but if you propose something reasonable, we’ll probably accept it”. In general, I see structural protection such as weather covers (see e.g. these ships) and “icing-resistant design” preferable over taking an existing design and installing enough trace heating on stairs and decks to get the class notation. Of course, certain systems and equipment such as lifeboat davits need to be duly winterized in all vessels, but in my eyes designing an “Arctic ready” offshore vessel would mean taking icing, cold ambient temperatures etc. into account already when developing the general layout of the vessel.
Anyway, I find the topic interesting and winterization/de-icing/anti-icing is definitely something I should study more, regarding both general design as well as individual components.
Regarding American OSVs, how many ships actually operate in regions where icing may occur? Aiviq and the few other support ships for Shell’s project (such as this one) come to mind.