Vessel operators may not hear sound signals or voices if the engine is not adequately muffled.
- A vessel's engine must have a muffler or exhaust water manifold for noise reduction or another effective muffling system.
- The use of cut-outs or exhaust stacks is prohibited.
- It is illegal to operate a powerboat or PWC, or allow others to operate, in such a manner that the noise level exceeds 86 decibels as measured by the Society of Automotive Engineers (SAE) Stationary Sound Level Measurement Procedures SAE J-2005 or as measured by the SAE Shoreline Sound Level Measurement Procedure SAE J-1970 at 50 feet from the vessel. You must submit to a noise level test if requested by a law enforcement officer.
- It is illegal for recreational boaters to use or have on board a siren of any type while operating on the waters of Alabama.