Here's a little more on it....
(b) A motorized recreational vessel that is operated in or upon
the inland waters, or in or upon ocean waters that are within one
mile of the coastline of the state shall be equipped at all times
with a muffler or a muffler system that is all of the following:
(1) In good working condition.
(2) In constant operation.
(3) Installed in a manner that effectively brings the vessel into
compliance with Section 654.05.