41:04:05:04.01Whistle
Section · Administrative Rules of South Dakota · View on sdlegislature.gov ↗
required. A Class 1 motorboat must be equipped with a whistle or other sound-producing mechanical device capable of a two-second blast audible for at least one-half mile. A Class 2 or Class 3 motorboat must be equipped with a power-operated whistle capable of a two-second blast audible for one mile.
Source: 10 SDR 120, effective July 1, 1984; 46 SDR 74, effective December 2, 2019.