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It's the Law


A vessel's engine must have a factory-installed muffler or exhaust system for noise reduction, or another effective muffling system.

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

Michigan law states that a vessel's muffler or exhaust system must prevent noise in excess of:

  • 90 decibels at idle from three feet away and…
  • 75 decibels when measured from the shore.