Why the heck are boats so loud??

[eponodyne]

Just came off watch on the riverine towboat I'm working these days. They've come a long way as far as crew comfort goes; 42" plasma TV, 1028374647823823789 channels to watch when we're not working, Internet access (obviously); but my stars and garters this thing is loud.

Twin v-8 Diesels (Cummins derivative) with a 6-cyl John Deere driving the generator... Of course my bunk is right on top of it. Shaft Bearings rumbling, water hammer off the props hitting the underside of the hull, the continual 60-cycle whine of the steering pump. It adds up. I get off the vessel after two weeks and generally go find someplace quiet to sit for a few hours, just so I'm not bellowing at people like I' ve been used to doing.

But why? Noise-reduction technology is available, proven, and (balanced against a new Cummins V-8) pretty cheap. It's not like a little insulation would eat up valuable cargo space, because the cargo is all in barges. I don't get it. I'd forgot how much the continual noise gets to me after a while. And then my deckhands want to know why I spend so much time on tow, away from them and away from the boat. I hold up a book and smile, but I strongly suspect they don't get it.

[Guillermo]

Originally Posted by eponodyne

Noise-reduction technology is available, proven, and (balanced against a new Cummins V-8) pretty cheap...

Noise and vibrations reduction techniques are available, yes, but they are not cheap at all, I'm afraid. There are specialized companies and people making a living on selling such studies and technologies.

There is even an 'International Ship Noise and Vibration Conference' held every two years. Last one took place in London only a couple of weeks ago (http://www.marinetalk.com/articles-m...0142736CE.html)

Just google around for 'ship noise vibration' or the like, to find out a wealth of info on the subject.

Here an interesting reading: http://www.safetycenter.navy.mil/acq..._ctrl_ship.htm

Cheers.

[FAST FRED]

Don't worry , with the lack of new crew members willing to take up the lifestyle , not only the pay , but the working conditions will get better...SOON!

My gripe is with the Cigarette boats that think 120DB is what makes boating fun.

If it were up to me , anything loud enough to hear would become a target.

Including Harleys!

FF

[StianM]

I love the sound from large displasement diesels, but the caterpilars and the cummins are just plain noice.

Working next to a Cat suck big time. I was doing the startup of the main switchboard on a diesel electric supply vesel with 5 cat's 1 1500kw and 4 2500kw and I can still hear them in my head

[Frosty]

I too love the sound of engines and have all my life. I like to listen to every part with a stethascope or screwdriver -its fascinating.

As long as Im not responsable for the machine at that time it lulls me to sleep.

Theres nothing like rumbling along on a Harley with straight throughs.--the noise bouncing back from trees or walls.

I think your in the wrong job.

However after a hearing check 4 weeks ago apparantly I have lost hearing at high frquencies due to loud machinery earlier in life. I had'nt noticed it but!!!!!

[Busman1965]

Another good reason to go back to slow turning diesel!! They are not noisy, and are actually soothing to listen too, like a heartbeat. I have a ancient 1 cyl diesel generator on my trawler, and I love the slow chug, chug sound to sleep by. I have been on other boats, with highspeed diesel generators, and they are just annoying. Sometimes the new stuff is not the best.

[Quietboats]

As a builder of electric powered boats, more than once i've heard the comment that they are too quiet. I tell the complainers to clothespin some waterproof basebal cards to the skeg in the area of the prop. Some people just don't think they are alive unless they leave their mark everywhere they go.

[Ike]

When on a boat you are essentially inside a drum. Noise is transmitted throught the hull by simple vibration. Everything on a boat vibrates, especially the engines. All that is transmitted and amplified by the boat itself. As was said, there is technology there is technology to dampen all this but it ain't cheap. And then there is the crowd that thinks loud is cool and sexy. Not just boats, motorcycles, cars, boom boxes and so on. Me, I lost hearing in my right ear a few years back which probably goes back to shooting 5 inch guns on the cutters I was on. Talk about loud.

[Frosty]

Surface propulsion is smooth and vibration free. All you can hear is engines. It has to be experienced to be believed.

I talked to a guy in the marina once he had just hauled his 60+ power boat to renew the shafts but could not get rid of vibration ,he was sickened by it, he said it was very noisy and uncomfortable to travel long distances.

[rwatson]

I'll join the anti-noise brigade - I am very interested in the surface drive comments.
I have been astounded how much less tired I get just in train-travel with those Bose noise compensating headsets.
I enjoy sailing because it is nice and quiet, and the outboard was only used when needed.
My Dad drove bulldozers for a living - we have to speak up these days so he can hear us.
And, noise = inefficiency which = money.

[Guillermo]

DIRECTIVE 2003/10/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 6 February 2003 on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (noise)
http://eur-lex.europa.eu/LexUriServ/...en00380044.pdf

The Code on Noise Levels on Board Ships reprints Resolution A.468(12) and Resolution A.343(9) on methods of measuring noise levels and noise exposure limits together with guidelines on instructions to seafarers and responsibilities towards crew members.
36 pp. PB. IMO Sales No. 814E.
http://www.imo.org/Safety/mainframe.asp?topic_id=1040

Code of Practice for Noise Levels in Ships
http://www.mcga.gov.uk/c4mca/mcga-se...e_external.htm

Recommended limits from this last:
- Machinery spaces A (intended to be continuously manned or for long periods of time): 90 dB(A), except for workshops for which the recommended limits are 85 dB(A).
- Machinery spaces B (not intended to be continuously manned): 110 dB(A)
- Machinery control rooms: 75 dB(A).
- Wheelhouse or roofed bridge, chart room and radar room: 65 dB(A).
- Bridge wings and at windows of roofed bridges and other listening posts: 70 dB(A).
- Radio room: 60 dB(A).
- Galleys, serveries and pantries: 75 dB(A).
- Normally unoccupied spaces: 90 dB(A).
- Sleeping cabins, Day cabins and Hospital: 60 dB (A)
- Offices, Conference rooms etc: 65 dB(A)
- Mess rooms, Recreation rooms, Recreation areas, etc: 65 dB(A) within accommodation and 75 dB(A) on open decks.
- Corridors, Changing rooms, Bathrooms, Lockers and similar spaces: 80 dB(A)
- Ship's whistle: The sound pressure level at listening posts (bridge wings, forecastle when the whistle is sounding not exceed 110 dB (A) and so far as practicable should not exceed 100 dB(A).

Cheers.

[Ike]

The problem with boat noise in the US is it regulated (or not regulated) by the states. The rules have gotten more uniform over the last 15 years or so but still there are vast differences, and some states have no noise regulation at all. Also the standard is rather subjective. In most cases it's what is called a pass by noise level. they use a DB meter and measure the noise level as you pass by at a set distance. The problem with that is the distance varies from state to state. Some states have a static noise, that is how noisy is it sitting at the dock. And Then some states have the time and manpower to enforce noise laws and others don't.

I'd like to see a Federal noise law for boats but unfortunately it would come under the EPA (as you can tell I don't have a high opinion) and they would have to treat it as noise pollution. It doesn't come under Coast Guard jurisdiction because it is not considered a safety issue. Anyway, it's all a pain in the neck.

the Euros did it the right way. The ISO created a noise standard and the EU adopted it as part of the RCD. Beside most europeans don't like loud nosiy boats (except Italians) A lot of loud fast muscle boats are built in Italy.

[safewalrus]

Unfortunately it's an American thing! You guys like lots of noise in everything you see and do! Guy I know married a girl from New England, beautiful girl and intelligent to! now you don't get may of those! But hell could she shout! As this guy said he spent the first three months of the marriage teaching her not to shout (I met them several years into the marriage and she was still loud then!). But back to the subject, I've been on many a Work Boat (AHTS etc) the Germans, Dutch, Norwegian and French are noisy but not that noisy but the American boats are TWICE AS LOUD! Mind you the Americans don't pad their accomodation as much as the rest - we pay you good! (better than most, far better) you want comfort as well? same with the American military you can hear their Landing Craft and boats coming way before they heave into sight, the Brits tend to purr along, they are running up your beach before you know they are there (has it's advantages!)

[Guillermo]

RCD exigencies for recreational craft are quite tight. We perform noise level measurements for RCD purposes and I found limit of 75 dB for a passing boat at 25 m really low. If Ike's saying on italian boats is right, I don't know how they manage to comply with the Directive....!

[Ike]

Guillermo, All I know is that Italian boats sold here in the USA are just as loud as the American go-fast boats sold here. Maybe in Italy they muffle them better to comply with the RCD. Having never been to Italy I can only judge by what they send over here. The big yachts are pretty quiet though.