Why on inflatable mattresses in Russian they write "Swimming in the open sea is forbidden", and in other languages - not always? Because the only additional threat to life that occurs when swimming on a mattress in the sea (not in a pond or pool) is that the wind takes it away from the shore with a person. Why are they only written in Russian? Yes, because only the Russian people do not throw their mattress in such a situation in time to escape floating, while the shore is not too far.