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Course Outline

Propeller guard

Several new technologies are available to reduce propeller strikes.

The devices fall into the following categories.

  • Guards: Devices that provide some type of physical barrier around the propeller. These include deflection devices, full cages, ring guards, ringed props, and “Kort Nozzles.”
  • Propulsion: Devices other than a propeller such as jet drives and pump jets.
  • Interlocks: Devices that automatically turn off the engine or sound an alarm. For example, a ladder interlock stops the engine or triggers an alarm when passengers use the ladder to enter or leave the water.
  • Sensors: Wireless sensors or other devices worn by boaters that shut off the boat’s engine or trigger an alarm if the wearer falls overboard.

For more information, visit the U.S. Coast Guard’s boating safety website:

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