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Wilson
07-19-2000, 08:26 PM
I am lining my motor box with lead sheathing. My wife dropped by the shop saw the lead and expressed reservations as to the safety of using such a product aboard the boat. She asked me if ``other people`` used lead as a insulator of noise. I said not many that I knew of, but I thought that , or read somewhere, that it was an effective sound barrier.

My better half has a wonderful habit of being right most of the time, any thought as to her safety concerns or effectiveness.

I also have some scrap lead that came from an x-ray room at the local hospital.(one 1200 lb. keel coming up) Again certain individuals have questionned how safe it was. Would there be any residual contamination left on/ in these materials.

Any thoughts would be appreciated.

Wilson Evans

Ken Liden
07-19-2000, 09:11 PM
Lead is used in several brands of noise insulation. Contact a marine insulation supplier.

Gary Bergman
07-19-2000, 09:20 PM
Nevermind the residuals, the lead itself warrants a rethink. Doing seismic retrofits in the Bay Area on buildings built when lead paint etc. were fashionable, has given us blue collar types quite an education on lead and its effect on humans. Unless you want to wear a respirator and change filters regularly, forget the whole idea. You touch the lead, if you don't, it still becomes airborne, and just the amount needed to write the word l e a d is toxic. When on your hands, you eat smoke and concentrate the stuff in your body. Lead levels of 25 ppm will render you irratible, forget your own name, give you stomach problems, I could go on and on, but the medical costs alone will far outweigh the 'savings' over other forms of soundproofing. Now about the 'radioactive stuff'. I do a lot of rod removal and storage worldwide from nuclear powerplants, etc. Never gets to a 'safe' level in your or my lifetime. Buy earplugs, live long, and enjoy your boat and life.

ishmael
07-19-2000, 09:44 PM
But Gary, he's talking about lead used in x-ray shielding, not radio-isotopes. I'm no radio-chemist, and you may well be right about the sheet lead giving off an oxide powder or sumpthin', but the old lead shielding for the ballast keel shouldn't be contaminated. If it had been used to contain something "hot" that might well be a different kettle of fish. I don't think the level of x-ray bombardment from an x-ray room would do anything to lead. Maybe the chemist'll chime in here and tell me off but I'm 99.9% sure that x-rays don't change lead's nuclear structure or contaminate it in any way. The chemist should be able to give a definitive answer on the lead sheet hazards too. When I used to build houses we worked with sheet lead for chimney flashing all the time. My only concern, and it's minor, would be that the heat of the engine might cause some kinda reaction. Help mister wizard. Best, Ishmael

[This message has been edited by ishmael (edited 07-20-2000).]

Phil Young
07-19-2000, 10:56 PM
Rule 1- Don't eat the lead.
If you observe rule 1 I reckon you'll be ok. Its not like paint which flakes off and floats around, and you aren't drinking water that's been in contact with it like the Romans did. I think a lot of commercial engine sound insulating material has a layer of lead. Stops the low end noise.
Isn't uranium heavier than lead? Might make a really good keel.

Tom Lathrop
07-19-2000, 11:14 PM
Thanks, Phil

A little reason would have helped Chicken Little too. If lead was as bad as Gary says, a lot of my friends would have expired a long time ago. It ain't good food, but just having solid lead around isn't going to turn you into a zombie overnight. Just wrapping lead around the engine is not the best way to go about reducing noise though. To be effective, the lead sheet needs to be mechanically isolated, which is why commercial sound deadening material usually is a foam/lead/foam sandwich.

Depleted uranium has been used for ballast keels in record seeking sailboats for decades. I think Eric Tabarly started it in the '60's, along with shifting water ballast.

Gary Bergman
07-20-2000, 07:22 AM
Chicken little was a fairytale, lead poisoning isn't. As I said, if you touch it you will eat it. You mean you will not check your oil, look at your engine, alternator, etc? Suit yourself, after all, it is a free country, right?

[This message has been edited by Gary Bergman (edited 07-20-2000).]

TomRobb
07-20-2000, 07:50 AM
Perhaps the Great Unwashed will stumble on a way to ingest some lead. The problem is vanishingly small if you don't use it for dinner plates or coffee cups. And the notion that x-rays would leave it radioactive is absurd. X-rays are very high energy photons. They aren't neutrons piling up in the lead neuclei leaving the lead radioactive.
Don't lick it clean. Don't grind it or cut it w/ a power saw. If you melt it, don't breathe the fumes.

[This message has been edited by TomRobb (edited 07-20-2000).]

ishmael
07-20-2000, 08:16 AM
Somehow this thread reminds me of the asbestos issue. Correct me if I'm wrong but what I know about "the sky is falling" attitude there is that it originated from a disease of the lung--common in miners of asbestos, who lived in a cloud of the mineral, and who also smoked cigarettes--called asbestosis (sp?). Somehow this terrible disease of a relative handful was translated to an EPA edict that no public building could contain any asbestos. This edict included floor tiles with asbestos that were set in concrete mortar and sealed in floor wax. The removal process, chipping away at floor tiles, boiler insulation cased in plaster etc, created an inhalant problem where, previously, none existed. I've always thought it would be interesting investigative jounalism to trace the money in that fiasco. The removal companies, dealing with "hazardous waste" after all, can charge outrageous prices and end up with a real problem when they are done. A problem that needs further remediation. Ah well, I gotta go. Ishmael

thechemist
07-20-2000, 08:45 AM
I have not the time for a proper reply right now, but Ishmael is spot-on. And further, always follow the money.

Ed Harrow
07-20-2000, 11:56 AM
Hey, wait a gosh-darn minute here, that's my line (follow the money).

All "good" science stuff I've read supports Ishmael's, and others, claim. If one eats and breathes it, it's not going to do one any good. Although, maybe that does explain a few things - I've used 50/50 Sn/Pb solder for years, and don't know how much lead I handled as a kid making ballast for one model or another. Then, of course, we had red (uranium) fiesta ware dinner plates...

Gary Bergman
07-20-2000, 04:09 PM
Got any friends dying from asbestosis? I do. Any with lead poisoning so bad that they can't remember who they are or who their children are? I do. Your only the 'rich companies' attitude sucks. Who do you think works for those companies? Obviously not you, or your attitude would be different. Later.

ishmael
07-20-2000, 04:43 PM
Hi Gary,
I don't have any friends with those illnesses. Since my responses have been perceived as insensitive to the plight of people you care about and to people with those illnesses in general, I apologize. Could you explain to us just how they got sick? I assume from what you've said they were working with lead paint or asbestos removal. What happened? I was working under the assumption that anyone doing that kind of work would always be using HEPA repirators. I've done my share of scut work in the building trades and I know I wouldn't choose to live in a respirator, day in and day out. The arguments about whether or not those materials really need to be removed can seem pretty coldly academic when people we care about are sick. But, I don't think lead paint is comparable to the sheet lead in the original post.

If your friends were poorly trained or equipped, by companies contracted to remove those materials, I hope they have good legal representation. I'm not by nature very litigious, but those contracts are extremely lucrative and to not train and equip the employees properly would be unconscionable. Take Care, Ishmael

P.S. I've deleted an earlier comment about drooling, in deference to Gary's sick friends. Given the circumstances, I deemed it a weak attempt at humor, and in bad taste.

[This message has been edited by ishmael (edited 07-20-2000).]

[This message has been edited by ishmael (edited 07-21-2000).]

Bill Sterling
07-20-2000, 05:38 PM
X-rays do not induce radioactivity in lead, nor do they induce it in you when you are x-rayed. If the shielding came out of a research facility it should be checked for radioisotopes, however, anyone who uses radioisotopes would check this before releasing any wastes.

Touching lead will not harm you (unless its molten or traveling as a bullet), just wash your hands. Solid lead DOES NOT vaporize or become airborne if left undisturbed and does not represent a breathing hazard if left undisturbed.

Peace of mind may be the real issue as with the new craze for "organic foods" (as opposed to inorganic?). Although no pesticides can be detected on organic food or food grown using pesticides, people are afraid of a perceived ubiquitous unseen evil. In truth, "organic" produce has been found to be contaminated with much higher levels of a known killer - e-coli.

Also, as mentioned in previous threads, you need antimony (4%) to give the lead strength. Your shielding probably doesn't have any.

Scott Rosen
07-20-2000, 06:05 PM
I wouldn't shy away from using lead in the form we're talking about here. Sure, lead poisoning is a terrible condition. But maybe you folks don't know about the medical procedure called chelation (sp?). It's a relatively painless and safe procedure for removing lead and other metals from your body. It's medically approved for the purpose and is administered by specially trained doctors at their offices. There is mounting evidence that chelation has other profound health benefits for the heart and circulatory system. If any of you are concerned about your exposure to lead, then I would suggest that undergoing chelation is much more effective therapy than merely complaining or making accusations. In any event, it can do no harm.

ford
07-20-2000, 06:50 PM
in 1984 I consulted a building advisory service about auditory insulation, they sent me to an architect who specialised in this. I wanted to insulate one apartment from the one next door. His advice was to insulate with sheet lead as density cuts out sound, so in went 900lbs of lead sheet. I told the tenants that it was in case of nuclear attack, but hey the insulation sure worked and everybody slept better thinking they were safe from the bomb.
I still chuckle about this when I think of it.
Apparently some form of lead impregnated vinyl [I think] is used in office buildings in the partitions.

Paul Frederiksen
07-20-2000, 08:25 PM
Gary,

I will not dispute that lead ingested into the system will cause illness or even kill you if you ingest enough. But I do think it is appropriate and not the least bit insensitive to rationally discuss the method of ingestion.

To the rest who are planning to use lead in your boats,

Having spent four years doing environmental remeadiation drilling in some of the most hazardous places on this continent (read Hanford, Sandia, Rocky flats, and some places that are still trying to keep it a secret), I am well trained in this area. Lead is NOT "friable" meaning it does not naturally desintigrate into airborne dust. Therefore breathing lead dust is unlikely unless you are grinding it to dust and propelling into the air. Lead particles are large and a simple respirator is more than sufficient to deal with this possibility. The quantities of lead required to cause harm are relatively high meaning that prolonged ingestion of very small amounts would cause harm. The definition of prolonged exposure in this case would mean something along the line of say being a tire mounting guy at the tire shop -- and handling the lead tire weights with bare hands -- and then eating food or smoking a cigirette without washing hands -- and keeping this up every day for many years.

The forementioned senario bears absolutely no resemblance to the occasional use of lead by today's boat builders. Sensible precautions for todays boatbuilders would include:
1. Wearing a simple respirator while melting lead to avoid breathing the fumes.

2. Wearing adequate protective clothing, to inclued boots, long pants, long sleeve shirts, welder's gloves while handling molten lead to prevent splash burns.

3. Learning proper pouring techniques to avoid mould failure or water/moisture accidents.

4. And cleaning up well afterward to remove residual contamination from hands and equipment.

There is a much greater danger of accidental injury or death from improper handling of molten lead than from contamination.

I would encourage everyone to avoid the "sky is falling" response to every hazard out there. Sometimes this can reach absurd proportions. I was at a class where a teacher stated that uranium was the most poisonous substance known to man. I told her that I would drink a gram of uranium if she would drink a gram of pure caffene. She declined.

It is much more useful to apply the appropriate precautions to each risk posed. My grandmother died of smoking three packs a day for 70 years. My father is certain I am going to die tomorrow if I celebrate a momentous occasion with a cigar once a year or so. Somehow he has lost his sense of proportion because of the loss of his mother. It is not insensitive to point out this loss of proportion. I miss my grandmother too but this does not mean that it is ok to change the significance of FACTS.

In this technologically advanced society it is possible to protect oneself from almost any hazard with products one can buy easily and cheaply on the market.

Gary Bergman
07-20-2000, 08:58 PM
I have one friend who's lead level was 38 at last blood test.When working retrofits in San Francisco, our blood lead levels are monitored once a month. He wears his respirator all the time while working, but smokes cigarettes. Smoking is illegal in a building under retrofit. This was at S.F. City Hall, not some fly by nite small affair. He would go outside on break to smoke, take off his gloves, lite up. Fingers were the delivery vehicle for the lead to the cigarette, lighted cigarette produces two types of lead; solid and gaseous, and concentrates the delivery to the glands in the mouth, fastest way in to the body. He was a foreman so about the only contact he had with the toxin was carrying an odd bit of material outside to the hazmat container and have another smoke. Very low level of exposure{ like pulling an access panel off your motor} over a long period. It's that complicated, but knowlrdge can be a deadly friend. As far as sensitivity, it's no big deal as if the toxins don't get us, some of us still fall off bridges, buildings, etc. It's more a matter of higher education. Some folks have a higher understanding of scarf joints than others, CPES, or whatever. But on lead, CALOSHA is way out front. They have to be. I'm not an OSHA freak, either. I built bridges and powerplants much faster and cheaper without them prior to 1974. Just added a lot mo injuries and lives to the pricetag. Time to move along. I think I'll pull a Cleek and bug out for a while. Fair winds, etc.

Alex Batson
07-20-2000, 09:03 PM
May I suggest you look into purchasing lead vinyl. The lead is sealed between layers of vinyl. It is very flexible and the lead is not exposed. I used sheets of lead vinyl to shield a dental x-ray unit at work.

[This message has been edited by Alex Batson (edited 07-20-2000).]

Kermit
07-20-2000, 11:01 PM
My greatest exposure to lead comes from casting lead alloy bullets and pure lead roundball. In addition to the precautions concerning the handling of any molten metals, previoiusly mentioned, I never cast in the house, always have lots of ventilation, and wash well after a shooting session, Since learning of the possibility of contamination from my clothes, I wear coveralls not used for anything other than casting, and shower before doing anything. Nothing I use when casting gets used for any other purpose. While I doubt there are serious lead poisoning hazards from my occasional casting sessions, I figure there's no reason to tempt fate.

That said, there are some who see absolutely no hazard in handling lead. The craziest I've known was a fella who shot a 20ga flintlock tradegun. He'd fire a fouling shot to get the bore caked up, and thereafter shot unpatched ball which he spit-lubricated by popping the ball into his mouth while he measured and poured the powder. Dumb.

If you decide to go ahead with your acoustical plans, go with caution. I assume there's some ventilation for this motor box. Where does this air go when exhausted? You might want to paint the lead to seal it. Maybe a use for CPES? Have you thought about building a double-walled box to seal the lead away from contact? There are probably some sensible safety practices that have been established by folks smarter that I. I'd seek advice, and be prepared to follow it.

You might want to consider what you owe to those around you when weighing risks. For instance, I used to be anti helmet law. Then I spent a piece of my life counseling and training institutionalized handicapped men. One day it dawned on me that several of the "guys" were brain-damaged from motorcycle accidents in those pre-helmetlaw times. They were visited by family and will be supported for the rest of their days by you and me.

I hope I haven't sounded harsh. Your wife may be right. Proceed cautiously.

Don Danenberg
03-18-2003, 11:59 PM
Sorry guys, just thought this thread might just get you to look into your available archives.
We've got a guy calling himself "thechemist" here, and being apologetic about it, as well.

mmd
03-19-2003, 06:57 AM
Our sponsor's sister publication - Professional Boat Builder - had an article in an earlier edition on the subject of noise reduction in yachts. Might be worth a bit of research and the cost of a back issue.

ken mcclure
03-19-2003, 08:39 AM
Originally posted by ishmael:
...Somehow this terrible disease of a relative handful was translated to an EPA edict that no public building could contain any asbestos....Heh. If you look back through the people who were instrumental in getting these "edicts" passed, you will find quite a number who are involved or related to the abatement industry.

Same thing is happening right now with mold/mildew.

Not that these things are not harmful, but rather that a little common sense would avoid problems.

NormMessinger
03-19-2003, 08:59 AM
Don Danenberg and Paul Frederiksen, where you all been? We haven't seen you here recently.

Paul, do you have any recent pictures of your Enu Mara? And thanks for your perspective on lead exposure. Right on.

Nicholas Carey
03-19-2003, 01:31 PM
You might check out http://www.acoustop.com/marine.htm or other similar products (try googling for 'marine engine noise insulation' or similar.

If you're going to use sheet lead...paint the stuff (both sides), if you're worried about airborne lead problems. And yes, Virginia, lead does oxidise over time: that's what red lead is, lead oxide. Lead also forms carbonates under the right conditions (white lead). And it produces a chloride (lead chloride, PbCl2) as well — something to consider in a saltwater environment.

Wear a good mask with a toxic dust filter rated for lead (not a nuisance dust filter). Just tell the nice lady at the industrial safety supply store what you need it for. Wash your hands, regularly. Vacuum with a HEPA vacuum cleaner every day if you're producing dust.

All that being said, you won't get that much noise reduction probably from the lead unless you acoustically de-couple it from the substrate (wall/bulkhead/etc) to which it is applied. One of the attractions of the purpose-built acoustical panels as in the above link is that they are a composite that accomplishes this.

[ 03-19-2003, 02:32 PM: Message edited by: Nicholas Carey ]

Howard Sharp
03-21-2003, 12:08 AM
If I can add my tuppence worth; seems to me that all backyard boatbuilders should avoid bringing lead anywhere near the home. The biggest danger from lead is not to us who are already stupid, but to the growing brains of children. The leading researchers in this area (including Dr.Herbert Needleman, whose work prompted lawmakers to end lead in gasoline) now believe that there is no safe dose of lead for children. The most upsetting result of low lead exposure is loss of intelligence. As a whole, children growing up today will be 7 to 10 IQ points brighter than their parents, simply because they have not been exposed to exhaust fumes from leaded gasoline. Low lead exposure also makes kids violent, and reduces their attention span. When I read accounts of guys casting ballast keels in their backyards, protecting themselves with respirators, while ignoring the risks to downwind neighbors, especially children, from what is essentially a backyard smelter, I cringe. Traces of lead can be carried on hands, clothes or the soles of shoes from the workplace into the house where it settles and concentrates in furniture and carpeting, ready for crawling babies and toddlers to pick up on their hands. There are non-toxic substitutes for lead, whether in paint (boric acid solution), or ballast (cast iron, concrete and scrap iron/steel). IMHO designers should always offer specs for non lead ballast. There's no reason why any of us should have to handle this stuff. Of course it is a wonderful sound insulator, but.... If you want to know more scroll down to the Needleman story in this script: http://www.pbs.org/now/transcript/transcript117_full.html

Howard Sharp
03-21-2003, 08:58 AM
Oops, make that 3 IQ points. I just read the script. redface.gif

Alan D. Hyde
03-21-2003, 10:10 AM
That point difference may come about all other things being equal.

But, of course, they aren't...

Alan

TomRobb
03-21-2003, 02:20 PM
:rolleyes:
Good grief. You'd think someone is suggesting putting plutonium in their toothpaste.
It ain't witchcraft guys. Get a grip.

Ken Hutchins
03-21-2003, 02:26 PM
A little lead poisoning can be good. I just encountered a bristle pig (porcupine) that decided to take up residence in my boat shed.

Dave Fleming
03-21-2003, 03:10 PM
In the latter years of my time as a boat builder I had migrated to Aluminum work. Mostly large motor yachts. Sound and vibration were major concerns. The engineer found a company called EAR Corp. as a maker of sound barrier material.
Sound is energy and to eliminate it you have to break the trail so to speak.
We used principally two products from EAR, ISODAMP a very heavy rubber/vinyl/neoprene material approx. 1/2 inch thick. It was cut actually bandsoared into pieces for placement between stanchion bases and the stanchion and as part of machinery mounts such as airconditioner compressors. For buikheads particularly on the opposite side from the engine room we used a thin but godawful heavy Barium filled neoprene sheet glued onto the vertical bulkheads and layed atop the bottom tanks. The insulation in the engine room itself was a foam filled perforated metal material approx. 1 1/2 to 2 inch in thickness.
To the best of my recollection we did not have any complaints from owners about sound/noise.
Well Lo and Behold! I found a photo on one such application of the Barium sheet and Isodamp pads.
Sheet is on top of double bottom tanks and engine room bulkhead, pads the blue layer, are atop the supports for cabin/stateroom subfloor.

http://www.imagestation.com/picture/sraid56/p79b021340a750a57da49015afb609801/fc784984.jpg

Cedarhill Boatworks
03-21-2003, 04:17 PM
Amen Tom Robb, and ditto!

Bob Cleek
03-21-2003, 08:23 PM
Seems like lead isn't going to bite you if you use it intelligently, like any other material. I've been working with lead in one form or another for all my 53 years and that included the "good old days" when men were men and all paint was LEAD! It doesn't seem to have hurt me any, why, just the other day, I was telling... I was telling.... ****... another "senior moment..." I can't remember what I was going to say... GODAMMIT!

Ian G Wright
03-22-2003, 03:23 PM
The engine on Patience is surrounded with foam/lead/foam acustic insulation, the cabin heater is mounted on asbestos/cement insulating sheet, the seams are stopped with both red and white lead, I smoke, I drink, I drive to the boat, before I got married I indulged in unprotected sex with multiple partners, rode and raced motor bikes,skiid off piste, earned a very good living as a Saturation Diver, I DID inhale and I eat too much.
Will I die?

IanW

thechemist
03-22-2003, 03:52 PM
As others have observd, lead metal just sitting there is not going to do much of anything to you. I believe it is STILL used today for balancing weights on automobile wheels. You wanna go right out to the garage and rip all those awful lead weights off your wheels? Better to be unbalanced than have rotating lead nearby.........

Lead in paint is another matter entirely. Lead oxide or carbonate, that stuff is naturally a powder, and if you lick your front door every day you will eventualy ingest enough that you won't care if you did or didn't lick your front door yesterday.

Little enough of anything will not harm anyone. Nature Herself has a natural background radiation level from that unlicensed fusion bomb 93,000,000 miles away. Ya gotta keep these things in perspective.

Our society has entirely too many "Merchants of Fear" selling "The Dangerous Environment" to the point where too many of us come to believe it all.

Asbestos is another matter. One of my staff had worked in a rubber-compounding plant for decades, and his lungs were so full of asbestos that they showed opaque on X-ray. He had absolutely no breathing problems whatsoever. He was killed in his middle-sixties by doctors at Kaiser, who told him he had influenza on three separate visits. He actually had a ruptured appendix, but that's another story. He had no breathing problems and no lung cancer because he did not smoke. That was the common denominator of him and his co-workers, whether or not they smoked [some who did not may have gotten a lot of second-hand smoke], because asbestos is a catalyst that causes many interesting chemical reactions and cigarette smoke contains many interesting chemicals in addition to its many interesting carcinogens.

If you leave asbestos alone it will leave you alone. Similarly, lead forms an adherent oxide film and then stays as is, for many many years. Depleted Uranium, now there's something that DOES oxidize, and DOES shed particles unless painted, and is an inherent carcinogen due to its radioactivity, and generates Radon gas as a natural radioactive decay product, and you might breathe it. It's awful. But it makes great weights for keels, and probably would work well as a lead-free wheel-weight material once we ban lead entirely.

Depleted Uranium would also make a great replacement for lead in bullets. No one would need to worry about being killed by its radioactivity...........

mmd
03-22-2003, 03:55 PM
Ian, almost certainly. The real question is, when! :D

Ken Hutchins
03-22-2003, 06:57 PM
I grew up in a house in Massachusetts that has a real solid lead water pipe between the main in the street and the house. I am sure there are many thousands of houses that have this. I'm sure glad that the only problem I have as a result of it is that I am so demented at 58 years of age that I am building a W O O D E N boat.
Now that I live in New Hampshire I expect that all the radon gas and arsenic in the ground will help preserve me and my boat for at least another 58 years.

ahp
03-22-2003, 08:04 PM
If you sell a house in Massachusetts, and we did, a radon gas test is manditory. We flunked. We had to knock about $1800 off the sale price to defray the cost of a power vent in the basement to suck out the radon. I used to have my office down there.

Lead in water supply pipes may not be a problem. If the pH is within certain values an inpermiable coating forms on the inside of the pipes. No lead goes into solution.

Depleated uranium in armour piercing rounds is devestating. When it penitrates through armour the jacket peals off, the uranium melts, bursts in to flame and sprays all around inside an armoured vehicle. The tank crew has no time to worry about lung cancer.

Phil Young
03-23-2003, 09:15 PM
I just got this picture of all those gun totin' Constitution quotin' 'mercuns, loadin' all them bullets in their guns, and loadin' all them smokes in their mouths. Maybe guns are more dangerous than we been thinkin'?