[image: Model HVM100 Human Vibration Exposure & Product Compliance Testing] Applications - Product Compliance Testing - Human Vibration - Whole Body Vibration - Hand Tool Vibration - Vibration Severity Measurement - Hand-arm Vibration - Tooling Vibration - Worker Exposures - Industrial Hygiene - Assess Risk of Injury
Features - Frequency weightings and measurements for Hand-Arm and Whole Body Vibration - Conforms to ISO Standards 2631 and 5349 - Simultaneous 3-channel Measurements: X, Y and Z axes, plus Sum (S) - Lightweight and Portable - operates from two AA batteries or AC power supply - Records up to 200 hours of measurement time history - Programmable AC or DC Signal output - USB and Serial Interface to PC (115.2 kBaud) Literature & Support <http://www.larsondavis.com/contentStore/mktg/LD_Downloads/LD_HVM100_0309_Lowres.pdf> *HVM100 Datasheet (for compliance testing) >>* <http://www.larsondavis.com/contentStore/mktg/LD_Downloads/LD_HVM100_0309_Lowres.pdf> <http://www.larsondavis.com/contentStore/mktg/LD_Downloads/LD_HVM100_IHV_0309_Lowres.pdf> *HVM100 Datasheet (For Industrial Hygiene applications) >>* <http://www.larsondavis.com/contentStore/mktg/LD_Downloads/LD_HVM100_IHV_0309_Lowres.pdf> <http://www.larsondavis.com/contentStore/mktg/LD_Downloads/LD_HVM100_IHV_0309_Lowres.pdf> *HVM100 Configuration Guide >>* <http://www.larsondavis.com/contentStore/mktg/LD_Docs/HVM100_Configuration_Guide.pdf> <http://www.larsondavis.com/Support/HumanVibrationSupport/HVM100.aspx> *HVM100 Support Page >>* <http://www.larsondavis.com/LinkClick.aspx?link=1489&tabid=1455&portalid=7&mid=2162> <http://www.larsondavis.com/TotalCustomerSatisfaction> <http://www.larsondavis.com/LinkClick.aspx?link=1482&tabid=1455&portalid=7&mid=2162> Human Vibration Exposure The Human Vibration Monitor 100 is a hand-held instrument for measuring human exposure to vibration, performing relevant calculations and providing overall metrics on its LCD display. Detailed vibration levels are easily stored in its built-in data logger, which can hold up to 100 separate time-history test files including all required metrics. This information can then be downloaded to a PC for analysis and archiving. *Product Compliance Testing* Measuring all three axes of vibration simultaneously greatly simplifies the setup of a test and enhances the repeatability and correlation of the vibration data. From the three channels of measured data, the HVM100 automatically calculates the important vector sum information and presents it as a fourth set of data values. For compliance with the latest measurement standards, the HVM100 employs digital filters for each channel that can be enabled as needed, and will never be obsolete - should standards change, the filters can upgraded - electronically! *Measuring Human Vibration* Human vibration in the workplace can be created by the operation of tools, plant machinery, and various vehicles. Different parts of the human body have resonances and, as you would expect, vibration at a resonant frequency is especially disturbing. As the transmissibility of vibration to an operator increases in amplitude or duration, it can cause annoyance, fatigue, and at higher exposures, a risk of injury. Human vibration in the workplace is categorized in two ways: 1. Whole-body vibration (WBV) where transmission is from the source through the feet or the buttock and into the body. 2. Hand-arm vibration (HAV) where transmission is through the hands and arms when using vibrating tools. The Larson Davis Human Vibration Meter (HVM100) is well suited for measuring whole-body and hand-arm vibration. It will analyze the data in accordance with the most current ISO requirements to calculate exposure metrics. The HVM100 is used with a miniature accelerometer that can be mounted using various handle adapters or a seatpad accelerometer. Using the Larson Davis Blaze® software, the operator can gather, manage, graph, and report the vibration exposure data. On Wednesday, June 12, 2013 5:33:27 PM UTC-4, Lidia wrote: > > Hi, Luca, > > I have listened to your recording of the Hum: It is great that you managed > to record exactly what I hear when the Hum is present! I mean, the Hum > itself sounds different, but there is always that "brown noise" which comes > with the Hum in Hum contaminated places and I cannot mistake it. Your > recording is amazing. > > I wiill try to find some spare time to read your research. Meanwhile, if > you feel interested in my own Hum recordings, please feel free to contact > me. They are quite interesting... Have you been able to read Victor Nixon's > findings on this forum? He sadly passed away last year and I believe that > the Hum killed him. > > An electrical engineer, a very good neighbour in my new residence, has > suggested that the Hum may be caused by the rectifiers which are used to > transform the AC to DC (he said that they always have a lot of problems > with them and the harmonics etc. they create). AC to DC is always used when > there are electronics on the power lines! He also said that actually it was > in Britain, in 1960s, when the "powerelectronics" has taken off (and when > the Hum has started)... I am not only hearing the Hum but experience > terrible body vibrations (and in my feet, constantly). > I have always felt vibrations (since the Hum invaded my life) when I stand > near CCTV cameras and security systems for remote control, also near the > electronic tills for cash payments, next to cash points - where also DC is > being used instead of AC.... This is worth exploring... > > Best Regards, > Lidia > > > 11 юни 2013, вторник, 13:18:31 UTC+1, Luca Rizzardi написа: >> >> Hi Trev. >> I suggest you to use a pair of good headphones or a subwoofer. >> I'm not sure I understand what you asked me: If you mean a spectrum peaks >> analysis, here it is: >> >> >> <https://lh5.googleusercontent.com/-MfBAFd2x0Og/UbcUeVLU-mI/AAAAAAAAAQ8/K_W_F60vTb0/s1600/Schermata+2013-06-11+a+01.34.54.png> >> In the peaks, the signal at 30 Hz reaches levels of about 59 dB SPL, >> which is conventionally just below the threshold of audibility, meaning >> that an individual with an average sensitivity will not be able to perceive >> it, while someone with a sensitivity even lightly above the media, in >> favorable conditions, could hear it. >> The spectrogram instead you can see it on the youtube video I linked! >> >> The instrumentation I used is of excellent quality: professional >> low-noise Schoeps and Sennheiser microphones that go down very low in >> frequency and a professional TASCAM digital recorder with battery operation >> to avoid direct induction from the power supply (the signals at 100 and 200 >> hz are radio signals from the mains). >> The home owner, a hummer, could hear the hum during recording, I don't. >> Sorry but my English is at school level, I don't speak it very well...I >> hope I understand what you meant. otherwise re-explain it :) >> >> Thank you >> >> Luca >> >> Il giorno lunedì 10 giugno 2013 15:06:58 UTC+2, Trev ha scritto: >>> >>> Interesting work Luca.. >>> I have to be honest and say it doesn't sound like my hum. Quite a low >>> level to get through my PC speakers maybe didn't help. >>> Did you get a harmonic frequency analysis at the same time- ie:spectral >>> spot freq peaks? >>> What I did pick up was a wider band, less pointed steady hum, than mine. >>> I know that your measuring gear could be getting part of the story, >>> though- Hum is notoriously difficult to nail. >>> ie: It could be co-incidental hum related noise at your location. >>> The big ?? is- was human hum pick-up detected at the same time and with >>> similar modulation? >>> Regards Trev >>> >>> >>> On Friday, 7 June 2013 00:48:10 UTC+1, Luca Rizzardi wrote: >>> >>>> Hello. >>>> I'm Luca, a sound engineer from Italy. >>>> I am not a hummer, but I spent the last 9 months studying The Hum, with >>>> the assistance of my university advisor and two hummers of the area. >>>> I studied a lot of the theories and publications about the phenomenon >>>> (in particular those of Chris Barnes and Tom Moir), analyzed testimonies >>>> and data from different forums like this and The World Hum Map and >>>> Database, studied the behavior of the phenomenon and formulated >>>> my hypothesis. >>>> Finally I have successfully recorded The Hum. >>>> >>>> On this link <http://www.youtube.com/watch?v=MhNCdzA6Fmc> you can >>>> listen to my recording and see the spectrogram. >>>> Frequency of the noise is around 30 Hz. >>>> >>>> This is my thesis >>>> <http://www.scribd.com/doc/144697878/Luca-Rizzardi-Conservatorio-C-pollini-Padova-The-Hum>, >>>> >>>> unfortunately in Italian language. >>>> I would be happy to exchange some opinions with you. >>>> >>>> Luca Rizzardi >>>> >>>> >>>> >>>> >>>> -- You received this message because you are subscribed to the Google Groups "Hum Sufferers" group. 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