Resource Documents: Japan (2 items)
Documents presented here are not the product of nor are they necessarily endorsed by National Wind Watch. These resource documents are provided to assist anyone wishing to research the issue of industrial wind power and the impacts of its development. The information should be evaluated by each reader to come to their own conclusions about the many areas of debate.
Author: Sugimoto, Takanao; Koyama, Kenji; Kurihara, Yosuke; and Watanabe, Kajiro
Abstract: This paper describes the development of a new sensor which uses a condenser microphone and a new system containing it as an element. The back of the microphone is covered with a seal chamber, which expands the frequency characteristic of the microphone to the infrasonic region. In addition, a windscreen is fitted to the sensor to reduce or eliminate wind noise. We developed a measurement system with this new sensor, installed it at a wind farm, and measured infrasound. The measurement results confirmed that the measurement system worked normally and could measure infrasound generated by wind turbines. Moreover, it was confirmed that the equivalent continuous sound level is highly correlated with the average rotor speed of a wind turbine.
Figure 7 shows the measurement result of October 25, 2007 19:16 as a sample, and Fig. 8 shows the result calculated by Eq. (2) and the calibration result of a G frequency weighting sound pressure level.
Figure 10 shows the relationship of the equivalent continuous sound level for 80 seconds (calculated from 240 measurement results by using Eq. (3)) and the average rotor speed.
Society of Instrument and Control Engineers Annual Conference 2008
August 20-22, 2008, University of Electro-Communications, Chofu, Tokyo, Japan
Download original document: “Measurement of infrasound generated by wind turbine generator”
Exposure-response relationship of wind turbine noise with self-reported symptoms of sleep and health problems: A nationwide socioacoustic survey in Japan
Author: Kageyama, Takayuki; Yano, Takashi; Kuwano, Sonoko; Sueoka, Shinichi; and Tachibana, Hideki
Abstract: The association of wind turbine noise (WTN) with sleep and physical/mental health has not been fully investigated. To investigate the relationship of WTN with the prevalence of self-reported symptoms of sleep and health problems, a socioacoustic survey of 1079 adult residents was conducted throughout Japan (2010-2012): 747 in 34 areas surrounding wind turbine plants and 332 in 16 control areas. During face-to-face interviews, the respondents were not informed of the purpose of the survey. Questions on symptoms such as sleeplessness and physical/mental complaints were asked without specifying reasons. Insomnia was defined as having one or any combination of the following that occurs three or more times a week and bothers a respondent: Difficulty initiating sleep, difficulty maintaining sleep, premature morning awakening, and feeling of light overnight sleep. Poor health was defined as having high scores for health complaints, as determined using the Total Health Index, exceeding the criteria proposed by the authors of the index. The noise descriptor for WTN was LAeq,n outdoor, estimated from the results of actual measurement at some locations in each site. Multiple logistic analysis was applied to the LAeq,n and insomnia or poor health. The odds ratio (OR) of insomnia was significantly higher when the noise exposure level exceeded 40 dB, whereas the self-reported sensitivity to noise and visual annoyance with wind turbines were also independently associated with insomnia. OR of poor health was not significant for noise exposure, but significant for noise sensitivity and visual annoyance. The above two moderators appear to indicate the features of respondents who are sensitive to stimuli or changes in their homeostasis.
Noise Health. 2016 Mar-Apr;18(81):53-61.
doi: doi: 10.4103/1463-1741.178478