I agree with the second floor. Generally speaking, the decontamination of the deck is done by fresh water. This is mainly because aircraft carriers, especially nuclear-powered aircraft carriers, have their own desalination equipment (although they often make ends meet), and even the fresh water for decontamination operations is not ordinary fresh water. It seems that it needs to be added, and most of the fire fighting fluid used for aircraft carriers is not water, but chemical foam. The main reason is that the structural theme of modern aircraft carriers is generally fireproof materials, and most of them will be fuel or ammunition in the future. At this time, using water is tantamount to adding fuel to the fire, and the corrosiveness of seawater is no small matter. Even ships such as aircraft carriers have anti-corrosion coatings, but there are many exposed parts such as weapon bases and catapults.

If there is not enough fresh water, seawater can be directly pumped from the sea (both the United States and Japan did this during World War II), but the damage to ships and equipment is relatively large. Later, with the progress of science and technology and the progress of all kinds of damage control, there is basically no such method of killing the goose to get the egg.