Your boat’s propeller (also known as the ‘prop’) is a dangerous piece of equipment for swimmers and towed sport participants. Props are underwater objects that spin quickly and force your boat through the water.

Contact with a propeller can cause devastating injuries or in some cases, even death.

Propeller Safety Equipment

If used properly, propeller safety equipment—such as a ‘propeller guard’, which cages the propeller—can help to prevent propeller strike injuries from taking place.


Additional propeller safety equipment may include:

  • Ladder interlocks: These are devices that sound an alarm or automatically shut down the engine when passengers use the boat’s swim ladder.
  • Wrist lanyard or engine kill switch: The operator wears this device and if they fall overboard, it will automatically shut the engine off, preventing the ‘circle of death’ scenario from occurring.
  • Electronic sensors: Your passengers wear these sensors and if they detect that a person has entered the water, the sensors will electronically shut the engine off.

How to Prevent a Propeller Strike Accident:

  • Never operate your boat near ANYONE in the water—including swimmers, divers, skiers, etc.
  • Always shut down your engine while passengers are entering or exiting the boat.
  • Make sure your passengers are seated before getting underway.
  • Ask a spotter to help you watch for people in the water.


Note: Each year, propeller strike incidents represent 4% of all boating-related fatalities in the U.S. Remind your passengers that even when the engine is off, the prop is sharp and can be a dangerous underwater object for swimmers to come into contact with.