Muffling Device Regulations in California Mufflers and Noise Level Limits

While operating your powerboat on California inland and coastal waters up to one mile from shore, it must be equipped with a muffler. Otherwise, you must have a means to prevent it from exceeding the noise levels listed below when they are measured by the Stationary Sound Level Measurement.

Muffling Device Regulations in California

Excessive noise levels measured at a distance of 50 feet from the motorboat are described as more than:

  • 90 decibels for engines manufactured before Jan 1, 1993.
  • 88 decibels for engines manufactured on or after Jan 1, 1993.

Noise levels measured from the Shoreline Sound Level Measurement Test should not exceed: 

  • 75 decibels.