What is the noise limit for a vessel's muffler or exhaust system at idle measurement?

The correct answer reflects the noise limit established for a vessel's muffler or exhaust system while idling. Specifically, the limit is 90 decibels when measured at a distance of three feet. This regulation helps to ensure that boats maintain a reasonable noise level to minimize disturbance to wildlife and other boaters, promoting a more enjoyable boating experience.

This standard is particularly important because high noise levels can affect both human interactions and marine environments. By keeping noise levels in check, the boating community can better align with local ordinances and environmental regulations designed to protect natural habitats.

Other options present different noise levels that do not align with the established regulations for idle measurements. Therefore, knowing the correct specification aids in compliance with boating laws and enhances the understanding of noise pollution management in recreational boating.