One of the things that have become increasingly apparent with the rise of electric cars is that when , those fires are incredibly difficult to extinguish. This is true of fully equipped fire crews on dry land, but imagine if one of those fires happened inside a ship at sea.

It’s not that hard to imagine, . The good thing was that, being a cargo ship, the number of crew on board was relatively minimal. What if it happened on a cruise ship? That’s the question that Norwegian cruise line asked of consulting firm Proactima AS when the Norwegian government asked it to start hauling vehicles on some of its coastal cruise ships. The answer, , was “absolutely not.”

Proactima AS determined that even though the ships were state-of-the-art and capable of handling a petrochemical fire, the risk of lithium or even a hydrogen fire was too great to justify. Further, if one did happen, the odds of putting it out without it endangering the lives of passengers weren’t worth the risk. This is because a lithium fire, in addition to burning incredibly hot, also produces a lot of toxic vapors.

Havila’s brand new ships use lithium storage batteries themselves, but the difference between these and the battery cells in a consumer EV is significant. For example, maritime regulations state that a ship employing these has to have them in a separate fire-proof room with a fire suppression system designed specifically for the battery type being used.

Will this decision by Havila Kystruten have an impact on other ferries or transport ships? Will, for example, the Washington State Ferry system place restrictions on hauling EVs? What precautions will large transport ships take to keep a situation like the one we saw on the Felicity Ace from happening again?

We reached out to Havila Kystruten for comment but didn’t hear back in time for publication.