Tag: Vibration and Noise Control Class

Dear Sir, Here is my reply. You asked for it, and it is lengthy. I am so grateful that you all are taking your time to give me your suggestions. I think a probable low frequency noise source, in addition to the trains, and obvious manufacturers’ noises, could be an asphalt batch plant that is located just behind our neighborhood. I drove by and listened and it is quite noisy with its clattering conveyer belts, giant blower, and the huge rotating mixing bin. I doubt we could have any influence on quieting such an operation. When we moved into our present house this plant was hidden by trees. Now that the leaves are gone, it is easily seen. Let the renter beware! We have tried all the things that were suggested in your e-mail. White noise machines and fans just added noise to the home and was not the solution I needed. The best brand of ear plugs worked well, but are kind of dangerous when you need to listen to what is going on in the house at night….like when someone might be sick and need help. ( mothers can appreciate this reason), or a tornado siren, etc. My husband must sleep and so I have the “night watch”. .The Bose headphones (thanks Grandma) did not do a thing for the low frequency, but one of my sons is enjoying them tremendously now for listening to music. I hate that she wasted so much money on something that didn’t work. I, too, have wasted lots of money buying several bundles of Fibrex to use as “bass traps” of sorts thinking that it might help. It did not. We did the realtor thing also. We moved from our first house recently. That house has its own story. We had moved to this town from out of state and did not know much about the area. Well, the house we bought was down the street from a gas well compressor. It was hidden in a wooded area and we did not know about it. Who would ever think that such a thing as a gas well compressor would be in a neighborhood…..only in Texas. The days we viewed the house happened to be some of the few days a year that the compressor was down for repairs or maintenance. On closing day when I walked up the stairs to turn the key in the door, I said to my self, “What is that noise.” After searching the neighborhood, we discovered the culprit to be a very old noisy natural gas driven compressor on a gas well. I fought that oil company for a long time and only was successful getting them to put up a wooden fence that did absolutely no good. Oil companies are King around here. They always expressed to me that they were compliant. They were, but this city has wimpy standards and codes that do not measure low frequency. We had spent lots of time, sweat, tears and money fixing up “this old house” and we did not want to move. We had redone the wooden floors ourselves, and I did not want to cover them up with carpet, even though that might have helped with the sound. We couldn’t afford to change out the old windows that were huge and had just been refurbished by me. Our home was built in an L shape facing the compressor. This was perfect for capturing the “waves”. They came right in through our large glass windows. In addition to that, there were metal awnings over each window acting like ears to reflect the sound in through the single pane windows. (I had refurbished those as well) The neighborhood was refreshingly quiet on the few days that “The Beast” was off for one reason or another. After three years of torment, the for sale sign went up. We disclosed the noise ( which probably brought our home value down) to the new buyer. She was not home much of the time anyway so she was not as bothered by it. The search for a quieter place was on. We were scared to think of buying again without knowing if “the sound” would be in that area too. , “ I had gone to look at houses for sale, just to see if I could hear how the house “sounded” and just to “test” a neighborhood. We decided just to rent. Little did we know that rental homes that are large enough for our family of six and that are in our price range are extremely hard to find in our town. We ended up having to grab a house when it became available just to get a decent place to live. As it turns out, we ended up moving from one frying pan to another frying pan so to speak. We have now been living in this rental for ten months and we are still plagued with noise problems. I say we because even though the others of our household are not as sensitive to LFN as I am, they still have to live with someone (the mom) who is and whose daily life is not as efficient as it could be were I able to sufficiently rest and relax. I went with our church on a mission trip to Mexico a couple of years ago. While up in a quiet mountain village, I discovered how wonderful peace and quiet were, and I realized just how much that LFN affected me while living in our bombarded home. Since we now rent, I can’t beef up the windows, but I have heard that double panes do not help with low frequency anyway. I’ll try to make a window plug to see if that helps. I can’t run the TV “off channel” because we need to concentrate and study at home. We are one of those homeschooling families. Also, that noise is annoying to my teenage daughter and me. You asked about whether or not other neighbors have had the same problems as I. I can’t tell you that. We haven’t gotten to know our neighbors very well yet. There are some factors to remember when questioning the neighbors about noise problems. Many in our neighborhood are retired and wearing hearing aids. They, of course, do not have problems with the noise. Second, if they did hear the offending frequency, they would be hesitant to say so in fear that this information might be something that could “go public” and cause their home values to go down. Third, low frequency noise is most often a source of annoyance to those fifty and older (I give away my age). The younger ones in the neighborhood have not yet reached that point. On a side note, there is an old man in the neighborhood who sits out in his attached garage with the garage door up for many hours a day. He will even sit out there when it is 100 degrees outside. I am just curious if he has a problem with LFN and is trying to escape it as I am. By the way, when I am out working in my ten by twelve foot shed (made of that composite siding stuff and sitting on wooden skids) I can’t hear or feel the vibration. This makes me wonder if the noise could be possibly ground borne. The LFN does seem to be worse when it is raining…..hum….saturated soil conducts noise very well doesn’t it. If the LFN was ground borne, would ….putting down a wood or laminate flooring that had a good coating of Green Glue behind it help. Is there any conclusive way to determine if LFN is indeed coming through a concrete slab? (I know this is some of that thousands of dollars of advice coming my way.) As was suggested, I am going to try to decouple the bed from the floor. I’ll order some sheets of sorbothane for that purpose. They are supposed to work better than rubber. What kind of instrument would measure the wall or slab vibrations? My son, who is now an engineering major (ME), once measured the sound with a microphone on his computer. Using music recording software, he measured the frequencies from 30 to 60htz or so. He had fun isolating the sound and turning it way up for all to hear and feel till we yelled at him to shut it off….ah teens. He captured it in the tile shower. So I know it is “out there” and not just “in my head”. It could be that I am one of those “hummers”. Read about them online. They can hear the Kokomo Hum, the Taos Hum, the London Hum, etc. There is even a low frequency sufferer’s society. This is your market for whoever invents a comfortable low frequency blocking head gear that can be worn at night. This wouldn’t block (as ear plugs do) the types of noise that parent’s need to hear at night. I would be interested in any tests like the one that one of the teacher’s mentioned ….measuring the frequency outdoors and comparing it to the indoor reading. I guess I just have to rent a device that measures what I need to measure. We would like to move, but as I said previously, I would not like to buy a home without knowing that I can block the offending noise that this town seems to produce whether from trains, underground gas pipes, well drilling, or chemical and manufacturing industries, etc. If we were to rent, we could not spend lots of money to “treat” the house for LFN. My husband likes his job and would like to stay in the area if possible. Me, I’d rather move to a small mountain village in Mexico. Or until then, I’ll just sleep with a pair of sorbothane shoe insoles smashed over my ears. I am glad you are teaching classes to train engineers in ways of mitigating noise and vibration, because ultimately these problems have a personal side and a personal face. If I have been a “textbook” case for you then so be it, and may you all become the best problem solvers in this area. If any of you have any other suggestions for me, send them my way. If you solve my problem, then my hat is (or should I say ear plugs are) off to you. Please do not share my e-mail address with the masses. My humble thanks, C