SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: Luckie Stiff on April 21, 2009, 09:53:58 AM
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There's always talk of how loud is too loud, I've done a little research and I found this info.
Info courtesy of CP Performance.
Boating Noise Limit Regulations By State:
SAE J34: The most precise measurement available, taken of a boat at a distance of 50 ft. with wide-open throttle (the near maximum noise of the boat). Although great for engineering standards, it is difficult for enforcement purposes in the field. The Coast Guard recommends 86 decibels (dBA), which most states have adopted as law.
SAE J2005: This measures the engine sound at idle with the microphone 1.5 m away. SAE recommends a limit of 90dbA for this method, which does not account for the speed or power of the boat.
SAE J1970: In realizing the enforcement difficulties of the previous methods, SAE designed this shoreline noise test enabling regulations keeping the boat under 75 dBA at 50 ft. by operation, not mechanics. The operator is responsible for controlling the noise of the boat.
Sound energy dissipates with distance, other sound and wind. A comprehensive study on sound with motorboats (but not including PWC) found that sound dissipates up to 9.9dBA when the boat travels from 50 ft to 200 ft away (4.8 dBA reduction from 50 to 100 ft, additional 5.1 dBA reduction from 100 to 200 ft.).
Both the National Association of State Boating Law Administrators (NASBLA) and the National Marine Manufacturers Association (NMMA) have Model Noise Acts, which our manufacturers follow as NMMA members. These requirements are in compliance with the SAE recommended dBA standards. NASBLA requires 88 dBA under SAE J2005, and 75 dBA under SAE J1970. NMMA recommends 90 dBA under SAE J2005. The Environmental Protection Agency has determined that 75 dBA at 50 feet is an acceptable noise level to protect public health and welfare.
Here's a spreadsheet showing all the states' regulations.
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So far so good, Skip. Still haven't had an issue with the open headers, but I worry about it, Kinda hard to be under 86 DB with anything. Deeper sounds will fluctuate SPL meters more than higher frequency sounds, a known fact.
What's it mean? Our deep throated Big Blocks are at a serious disadvantage compared to the twin engine 2 cycle Rice Burners that are actually louder.
Great info, printed all this out to keep in both boats. Might even laminate them for future use. (It's coming, I just know it!)
Honestly, though, I think that unless your driving like an ass, they'll leave you alone. At least I hope for now. ;D
My fear is this, and wanted to pass this on. Here's what it has come to. We've seen an extreme rash of government agencies visiting our stores and fining the piss outta them. What they are doing is generating income for Job Security, after recent rumours of severe Federal, State and Local layoffs. Weights and measures, OSHA, Fire Marshalls, Building Inspectors, etc etc etc. This is no sheit. We had a store on the west side fined $15000 for not having 2 store key lock boxes (for the police and fire) on the building (A new regulation (2008) on new construction, this store is 10 years old!) and "No building permit on file". We HAD A COPY OF IT, still, it wasn't filed by the city, and it's OUR FAULT!
They are being told to generate funding. I don't care what they say (They all deny it).
Makes sense. with 5-10% of homes in foreclosure, no property or school taxes being paid., unemployment higher than it's really ever been (If you count under employment). Those being paid from those taxes? Well, you do the imagining.
Welcome to Obamanomics!
Tom, Check your Fire extinguishers and don't put anything within 18" of a sprinkler head, they're coming.
Ray