When boating, if you see a blue and white international code flag a (or alfa flag), what distance away from the displayed flag should be maintained?

When boating, if you see a blue and white international code flag a (or alfa flag), the distance away from the displayed flag that should be maintained is 200 feet.
That is the optimal distance that you shouldn't cross under no circumstances, because then you would be invading another country which is illegal. 

Blood transfusions were rarely done and often fatal; they were outlawed until the nineteenth century.