The exhaust of every internal combustion engine used on any motorboat shall be effectively muffled by equipment so constructed and used as to muffle the noise of the exhaust in a manner which reduces the maximum machine operating noise level to not more than 82 decibels on the A scale at 50 feet, in a normal operating environment. The use of cutouts is prohibited except for motorboats competing in a regatta or boat race approved as provided in section 3316 of this title, and for such motorboats while on trial runs, during a period not to exceed 48 hours immediately preceding such regatta or race and for such motorboats while competing in official trials for speed records during a period not to exceed 48 hours immediately following such regatta or race. (Added 1983, No. 212 (Adj. Sess.), § 2; amended 1989, No. 65, § 6.)