(2) No person operating a motorboat shall allow any person to ride or sit on the starboard or port gunwales or on the transom of the boat while underway at a speed in excess of five miles per hour unless the motorboat is provided with adequate guards or railings.
(3) No person operating a motorboat shall allow any person to ride or sit on the bow, gunwale or transom railings while underway.
(4) Nothing in subsection (1) or (2) of this section:
(a) Is intended to prevent passengers or other persons aboard a boat from standing on the bow of the boat in order to moor the boat to a mooring buoy, float or dock or to cast off from such a buoy, float or dock or for any other necessary purpose; or
(b) Applies to a boat rigged and equipped as a sailboat when operating under sail power. [Formerly 488.140]