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Course Outline

Vessel operators may not hear sound signals or voices if the engine is not adequately muffled.

  • All vessel engines must be equipped with an effective muffling device or underwater exhaust.
  • The noise level of any motorized vessel must not exceed these limits.
    • Stationary test limit:
      • 90 decibels for engines manufactured prior to January 1, 1991
      • 88 decibels for engines manufactured on or after January 1, 1991
    • Moving test limit as measured on the A scale and from a distance of 50 feet:
      • 84 decibels for engines manufactured prior to January 1, 1991
      • 82 decibels for engines manufactured on or after January 1, 1991
  • A vessel may be equipped with a switchable device that will reduce the exhaust noise level in compliance with the decibel limits.
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  • Topic 8 of 19
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