Propeller Fatality Permit mockup used as example of means U.S. Coast Guard could use to regulate boat propeller fatalities using a cap and trade system. Not a Coast Guard document.
Houseboat Propeller Regulation Proposed and Withdrawn by USCG: Analysis by PGIC
History of Boat Propeller Safety
Mitigating Boat Propeller Injuries & Fatalities Chart
Four Volume Review of the Boating Industry’s Boat Propeller Guard Product Liability Defense