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Resource Documents: Impacts (114 items)


Also see NWW "costs/benefits" FAQ

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.

Date added:  August 7, 2014
Germany, Noise, RegulationsPrint storyE-mail story

Feasibility study on effects of infrasound

Author:  Krahé, Detlef; Schreckenberg, Dirk; Ebner, Fabian; Eulitz, Christian; and Möhler, Ulrich

This feasibility study evaluated the state of knowledge about the effects of infrasound on human beings, the identification of infrasound sources and the potential concerns in Germany due to infrasound. Furthermore, a study design was developed for a noise impact study concerning infrasound immissions. Based on these findings, recommendations for the further development of regulations on immission control were made. The study led to the following conclusions:

June 2014, Umweltbundesamt (Federal Environmental Agency, Germany)

Download original document: “Machbarkeitsstudie zu Wirkungen von Infraschall: Entwicklung von Untersuchungsdesigns für die Ermittlung der Auswirkungen von Infraschall auf den Menschen durch unterschiedliche Quellen”

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Date added:  August 6, 2014
Filings, Maine, Noise, RegulationsPrint storyE-mail story

Brief of Fox Islands Wind Neighbors, Vinalhaven, Maine

Author:  Fox Islands Wind Neighbors

It is a sad spectacle for the citizens of the State of Maine (and more than that for the Fox Islands Wind Neighbors, the “Neighbors”) to see the Department of Environmental Protection (the “DEP”), the state agency charged with the responsibility to protect us from environmental harm, align itself with Fox Islands Wind, LLC (“FIW”) to grant a de facto exemption from the Noise Rule and then responding in court with claims that it has the absolute right to do so without judicial oversight. It is even worse that the Commissioner responsible for this was in a highly compromised position, having been employed as an industry lobbyist for the very same law firm asking for such special treatment weeks before she issued the Condition Compliance Order (the “CCO”) at issue in this appeal.

A. Issues about Excessive Noise in Connection with the Licensing of the Project.
B. Noise Complaints Following Commencement of Operations.
C. DEP’s Finding of Non-Compliance and FIW’s Refusal to Cooperate.
D. Events Leading to the Challenged Condition Compliance Order.

I. The Superior Court correctly ruled that it had jurisdiction over the petition for review and that the neighbors have standing.
II. The Superior Court correctly ruled that the CCO is unlawful.
III. The Superior Court erred by dismissing the neighbors’ First Amendment retaliation claim.

For the reasons stated above, the Neighbors respectfully request this Court to affirm the decision of the Superior Court that the CCO is invalid as a product of arbitrary and capricious action, without substantial evidence to support it, and an abuse of discretion and hold that the Neighbors have established a valid First Amendment retaliation claim under Rule 80C, with allowance for an award of attorney’s fees or, in the alternative, that they have set forth a plausible claim under Section 1983 of First Amendment retaliation that may proceed on as an independent claim. The Neighbors further request that the matter be remanded back to the Superior Court so that the matter can be remanded to the DEP with detailed instructions on the parameters of a valid CCO.

Dated: August 5, 2014

Rufus E. Brown, Esq.
Portland, ME
Attorney for the Fox Islands Wind Neighbors and the Individual Petitioners

Download original document: “Brief of Fox Islands Wind Neighbors”

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Date added:  August 6, 2014
Australia, NoisePrint storyE-mail story

Wind Turbine Noise: a simple statement of facts

Author:  Waubra Foundation

Emission of Sound and Vibration

Note:  ILFN = infrasound and low-frequency noise.

1. Wind turbine blades produce airborne pressure waves (correctly called sound but which, when unwanted, is called noise) and ground-borne surface motion (vibration).

2. Recent measurements have indicated that turbines generate vibrations even when shut down,[1] presumably from the wind causing the flexing of large blades and the tower structure, and that this vibration (when turbines are shut down) can be measured at significant distances.

3. The airborne energy manifests as sound across a range of frequencies from infrasonic (0–20 Hertz [Hz]) up through low-frequency sound (generally said to be below 200 Hz), and into the higher audible frequency range above 200 Hz. (Hertz is the variation in a particular changing level of sound pressure, as the rate of cycles [or period] per second).

4. Sound at 100 Hz is audible at sound levels of around 27dB (decibels) for an average person, whilst the level of sound required for average audibility rises quite quickly below frequencies of, say, 25 Hz. Sensation, being non-auditory but bodily recognition of airborne pressure waves, occurs at lower pressure levels of infrasonic frequencies than can be heard. At infrasonic frequencies the “sounds,” i.e., pressure waves, exist and may be detected by the body and brain as pressure pulses or sensations, but via different mechanisms than the perception of audible noise.

5. Periodic pressure pulses are created by each turbine blade passing the supporting pylon. This is an inherent consequence of the design of horizontal axis wind turbines. These energy pulses increase with increasing blade length, as does the power generating capacity. People living near turbines have described the effect of these pulses on their homes as “like living inside a drum”.

6. Larger turbines produce a greater percentage of their total sound emissions as low-frequency noise and infrasound than do smaller turbines.[2] Therefore replacing a number of small turbines with a lesser number of larger turbines, whilst keeping the total power output of a wind project constant, will increase the total ILFN emitted by the development. This effect will be compounded by increased wake interference, unless the turbines have also been repositioned further apart in accordance with the spacing specifications for the larger turbines. Wake interference results in turbulent air flow into adjacent turbines, with a consequent loss of efficiency, and increased ILFN generation.

7. If estimated sound contours have been used in seeking planning permits, then replacing the permitted turbines with larger turbines will significantly increase the persistence of the wake turbulence, and thereby the sound emitted by adjacent turbines (and the proportion of ILFN emitted) will be significantly above the predicted contours. This is what occurred at the Waubra development, and will occur when a lesser number of larger turbines are used to maintain the generating capacity of the development, as occurred at Macarthur (both projects being in Western Victoria).


1. Infrasound is common in our world, but most natural infrasound is irregular and random, or is caused by a transient event (e.g. earthquakes). Some frequency bands below 20 Hz have been shown experimentally to cause a physiological stress response in humans at below audible levels.[3] Industrial machinery noises are often regular and repetitive, as is the case with wind farm noise emissions, across the audible and infrasonic frequency spectrum.

2. Infrasonic pulsations travel much larger distances than audible noise and easily penetrate normal building materials, and once inside can resonate building elements (i.e., increase in impact inside rooms).[4]

3. Infrasonic pulsations from a single 4 MW wind turbine were measured 10km from their source by NASA researcher William Willshire in 1985.[5] Recent data collected by acoustician Les Huson in Australia and in the United Kingdom at onshore and offshore wind developments has shown that attenuation (reduction in sound level with increasing distance from the source) can be much less than the 3dB per doubling of distance found by Willshire in 1985.[6]

4. Some acoustic pressure pulsations are relatively harmless and indeed even pleasant to the body, including waves on a beach. Organ music at frequencies just below 20 Hz generates “feelings” in people that can be either pleasant or unpleasant, and has been designed to produce emotive effects.[7] Once it is understood that different frequencies can have very different effects on humans, it is easy to understand the importance of accurate acoustic measurement.

5. Dr Neil Kelley and his colleagues from NASA demonstrated in the 1980’s that wind turbine–generated energy pulses and noise in the infrasonic and low-frequency bands, which then penetrated and resonated inside the residents’ living structures, directly caused the range of symptoms described as “annoyance” by acousticians and some researchers.[8] A more accurate general descriptor would be mild, serious or intolerable “impacts”.

6. Residents and their treating medical practitioners know these symptoms and sensations include repetitive sleep disturbance, feelings of intense anxiety, nausea, vertigo, headaches, and other distressing symptoms including body vibration. American Paediatrician Dr Nina Pierpont gave this constellation of symptoms the name “wind turbine syndrome” in 2009.[9] Dr Geoff Leventhall, a British acoustician who was one of two peer reviewers of the NHMRC’s 2010 Rapid Review, has accepted these symptoms and sensations as “annoyance” symptoms, which he attributes to a stress effect, known to him to be caused by exposure to environmental noise, one source of which is wind turbine noise.[10]

Wake Interference and Turbulence

1. Historically it was accepted that wind turbines should be no less than 5–8 rotor diameters apart, depending on the direction and consistency of the prevailing wind, with the higher separation being for turbines in line with the major wind direction. This was accepted industry practice and, as an example, was explicitly specified in the 2002 NSW SEDA handbook.[11] The purpose of this specification is to minimise turbulent air entering the blades of an adjacent turbine. As noted above, turbulent air is associated with increased sound levels and infrasonic pulsations.[12]

2. If a significant proportion of the wind blows at a right angle (90°) from the major direction used for turbine layout it follows that turbine spacing should be 7 or 8 rotor diameters in both directions. It should be noted that the 7–8 rotor diameters number is a compromise between ensuring smooth air inflow to all turbines (and hence less noise and vibration) and packing as many turbines as possible into the project area. Research conducted at Johns Hopkins University in 2012 showed that the best design for efficient energy extraction suggests wind turbines should be 15 rotor diameters apart.[13]

3. It is increasingly evident that some projects are not laid out in accordance with accepted specifications to reduce turbulence, which in turn significantly increases acoustic emissions including audible noise and infrasonic pressure pulses. The consequences of increased turbulent air entering upwind-bladed wind turbines resulting in increased generation of impulsive infrasonic pressure waves and low-frequency noise were known to the industry in 1989.[14] Recent projects with turbines positioned inappropriately too close together should not have been given final approval by the responsible authorities.

4. Yawing (side to side movement of the blades caused by minor wind direction changes) is also known to increase wake interference.

Transmission of Energy Pulses

1. Information on the different attenuative and penetrative properties of infrasound and audible sound are discussed above.

2. Topography, wind speed, wind direction, wind shear, and ambient temperature will also have an impact on noise emissions and how that sound travels.

Noise Guidelines for Turbines

1. Many acoustic consultants and senior acousticians have known that wind turbines produce pulsatile ILFN as the blades pass the tower. It was common knowledge in the 1980’s, from research conducted by Dr Neil Kelley [15] and NASA researchers such as Harvey Hubbard,[16] that the pulsatile infrasound generated by a single downwind-bladed wind turbine and other sources of ILFN such as military aircraft and gas fired turbines penetrated buildings, amplified and resonated inside the building structures, and directly caused “annoyance” symptoms including repetitive sleep disturbance.[17]

2. Long-term sleep disturbance and chronic stress symptoms (accepted as “annoyance” symptoms), are well known to medical practitioners and clinical researchers to damage human health. Dr Kelley was quoted in 2013 as advising that the conclusions from his research in the 1980’s were equally relevant to modern turbine designs,[18] and this seems to have been confirmed in the preliminary results of acoustic measurements commissioned by Pacific Hydro and conducted by acoustician Steven Cooper at the Cape Bridgewater (Victoria) development.[19]

3. The New Zealand and Australian Noise Standards for wind projects were written by the then uninformed planning authorities. They were based on the UK ETSU 97 standard, also an uninformed document.[20,21]

4. Despite information being available from the Kelley research in 1985 specifying recommended exposure levels of ILFN which should not be exceeded,[22] the respective Australian guidelines only specified limits for audible, filtered, sound levels expressed as dBA outside homes; so there are no recommended limits or requirements to forecast, or to measure, ILFN levels or vibration inside homes neighbouring wind projects.

5. Permitted sound levels across most Australian States for all industrial equipment are background noise levels plus 5dBA or 35dBA whichever is less, whereas for wind turbines they are background plus 5dBA or 40dBA whichever is more. There is no scientific evidence or reason for this difference. An increase of 5dBA represents an approximate doubling of the sound level. Most rural environments have a background noise level of 18dBA to 25dBA, approximately averaging 22dBA at night. This represents a huge increase in audible sound. Increases of 10dBA at night are long known by acoustic consultants to raise complaints, and increases of 15–20dB are associated with widespread complaints and legal action. Averaging measured levels of sound across too-wide frequency bands also allows the hiding of sound pressure (level) peaks to which the ear responds, understating the true extent of facility noise emission levels.

6. World Health Organisation (WHO) Night Noise Guidelines for Europe quoted the 1999 WHO Community Noise Guidelines: “If negative effects on sleep are to be avoided the equivalent sound pressure level should not exceed 30 dBA indoors for continuous noise”.[23] Cities have a higher background noise than country areas. Denmark limits indoor noise from industrial sources, including wind turbines, to a maximum of 20 dBA at night.[24]

7. The currently permitted outdoor noise level in New Zealand and some Australian states has been ameliorated somewhat by the addition of a deduction of 5dBA from the 40dBA limit to allow for especially quiet environments.

8. History has shown that these Australian guidelines were based on ETSU 97 from the UK, and were expressly designed to encourage development of the wind industry, not to protect the health of rural residents from wind turbine noise. Predictably, because the Kelley criteria limiting exposure to impulsive ILFN were ignored,[25] these guidelines have turned out to be completely unsafe.

9. It is therefore necessary to predict and measure sound pressure levels across the full spectrum of frequencies in order to predict and control sound energy impacts on project neighbours.

Compliance with Permitted Noise Conditions

There are several problems associated with validating compliance.

1. Compliance is generally carried out by an acoustician or acoustics consultancy, paid directly by the owner or operator of the project. In one case a wind turbine manufacturer has contracted the acousticians directly, making the results even more questionable.

2. Compliance is of utmost importance to all parties with a financial interest in the development, but it is critical to families that neighbour the projects.

3. There are many ways that data measurements can be rigged (faux compliance): measuring instruments placed under trees or too close to buildings; waiting for optimum weather and wind conditions; not measuring for long enough continuously, recording in octave bands that are too broad and other averaging techniques. Operators may also reduce operational noise by reducing power output (with blade angle changes and slowed rotation) to reduce the noise during the monitoring period. Operators may also refuse to provide wind turbine facility operating data from test periods, claiming that it is “commercial in confidence”, thus making it impossible to verify actual operating conditions.

4. It would therefore be both appropriate and necessary for all projects to have their compliance independently audited.

5. Sufferers will not escape disturbance to their sleep and damage to their health even if a project is properly compliant with its permit conditions and noise guidelines, as preliminary findings of the acoustic survey commissioned by Pacific Hydro, conducted by Steven Cooper, have recently demonstrated.[26]

6. A compliant project may still cause damage to neighbours for numerous reasons. First, the standard refers to dBA only and thereby omits reference to ILFN; and second, even with regard to audible noise, the standard refers to a maximum of 40dBA outdoors, whereas every other form of industrial or other noise in country and city is limited to 35dBA maximum. There is no technical basis for such an aberration, and it is clearly (intended or not) discriminatory. Third, in quiet rural environments, even 35dBA will be intrusive and loud if the background level is below 25dBA, which is not uncommon. The ear responds to the peaks of sound levels, not the averages. The wind turbine noise standards all refer only to averages, and exclude ILFN, and do not account for the human response, so cannot protect people from predictable serious harm to their health.


23. – See p 110 for background to 30dBA inside bedrooms – sourced from the 1999 WHO Community Noise document, which can be accessed at
24. – See p 9 for the Danish LFN criteria indoors overnight
25. – See footnote number 10

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Date added:  August 2, 2014
Australia, Health, Noise, VermontPrint storyE-mail story

Wind noise and adverse health effects

Author:  Reider, Sandy

Public Service Board Hearing, July 29, 2014:

Good afternoon. My name is Sandy Reider, I am a primary care physician in Lyndonville, and I have been practicing clinical medicine in Vermont since I received my license in 1971. In the interest of full disclosure, I am not being paid for involvement in this issue, nor did I seek this out; rather, it found me by way of a patient I had known well for several years, and who, in late 2011, suddenly developed severe insomnia, anxiety, headaches, ringing ears, difficulty concentrating, and frequent nausea, seemingly out of the blue. This puzzled us both for a few months before we finally came to understand that he suffered from what was, then, a relatively new clinical entity known as “wind turbine syndrome”, related in his particular case to the comparatively small NPS 100 KW turbine that began generating power atop Burke Mountain in the fall of 2011. In the course of the 2012 legislative session, I described this patient in detail in testimony for the Senate Natural Resources and Health Care Committees, as well as the Governor’s Siting Commission. Since his symptoms were so typical and similar to those described by thousands of other individuals living too close to large wind turbines all over the globe, I have attached my testimony for the Senate Health Care Committee and encourage you to review it for its very characteristic description of what it is that this board, I trust, hopes to mitigate by recommending more protective sound standards for these industrial wind installations. I should add that I have seen 4 additional patients living close to the large Sheffield and Lowell projects, as well as an individual living near another single NPS 100KW turbine in Vergennes. All presented with similar, though not identical, symptoms to those described in my testimony.

That there have already been so many complaints here in Vermont related to wind turbines suggests that the current noise standards may be inadequate. Either the utilities have been regularly out of compliance with the current existing standards ( Shirley Nelson’s detailed daily records suggest this has indeed occurred with some regularity ) and/or that the scientific data and studies upon which the current noise standards are based is incomplete, or possibly just plain wrong.

Over the past 2 years I have reviewed much of the relevant scientific literature, and out of my 42 years of experience and perspective as a clinician, respectfully offer the following observations and comments.

Firstly, I do not doubt at all that these large turbines can and do cause serious health problems in a significant number of persons living nearby, even though the vibrational-acoustic mechanisms behind this harm are not yet completely understood (1,5). Repetitive sleep disruption is the most often cited adverse effect, and disturbed sleep and its resulting stress over time is known to cause or exacerbate cardiovascular illnesses (2), chronic anxiety and depression, as well as worsening of other pre-existing medical problems . This is especially concerning for the most vulnerable among us … children, the elderly, those who are naturally sensitive to sound, or prone to motion sickness or migraine headaches, and, as mentioned, those who are unwell to start with.

The position adopted by developers of large industrial wind projects, and thus far supported by regulatory and health agencies, has been that there is no evidence of a direct effect on health from wind turbines; rather, that the claimed adverse health effects are indirect, due mainly to the individual’s negative attitude about the wind turbines ( so-called “nocebo” effect ), and therefore it is their fault, it’s all in their heads, and so on. Not only is this incorrect, it is disingenuous. There is simply no clinical justification for ignoring harm being done to individuals and communities, whether direct or indirect, on these grounds… simply put, harm is harm, whatever the mechanism.

However, good evidence for direct adverse effects has existed since the mid-80’s when Neil Kelley headed a group of researchers, under the auspices of the US Department of Energy and NASA, and found conclusive evidence that adverse effects, very similar to those that describe “wind turbine syndrome”, were due primarily to very low frequency sound and inaudible infrasound (6). This role of infrasound was subsequently confirmed by Kelley’s team under controlled laboratory conditions, and resulted in a complete redesign of turbines from the downwind trestle-mounted turbines to today’s upwind turbine on a single massive tower. Furthermore, he recommended protective maximum levels of this low frequency sound.

[T]he joint radiation levels (expressed in terms of acoustic intensity and measured external to a structure) in the 8, 16, 31.5 and 63 Hz standard (ISO) octaves should not exceed band intensity threshold limits of 60, 50, 40 and 40 dB (re 1 pWm –2) more than 20% of the time. These figures compare favorably with a summary of low-frequency annoyance situations by Hubbard.

( It is worth noting that very often infrasound levels are higher inside a building than outside, the structure acting as a resonating chamber and amplifying the lower “vibration” frequencies. Thus measurements for low frequency sound should be made inside the structure as well as outside. Also, low frequency sound levels are not only building design and geometry specific, but also site specific, especially in a place like Vermont where the topography and climactic conditions are so variable. There may be unacceptable indoor infrasound levels in one home, while another home over the hill may have undetectable or very low levels. )

The wind industry’s assertion that the Kelley study is irrelevant and that infrasound levels are negligible with the current, newer turbine design and may be ignored is unfounded, and more recent evidence confirms this ( 2012 Falmouth study by Ambrose and Rand ( Bob Thorne’s excellent quality of life study in 2011 (12); Steven Cooper’s preliminary results in Australia, final results due in September 2014 (11); and others ). The aforementioned studies were performed by independent professional acousticians not connected to the wind industry. Incidentally, the severely affected patient described in my 2012 testimony never did perceive any audible noise from the turbine ( and this is quite typical, the sound is more felt than heard ), nor did he harbor any feelings pro or con about the installation when his problems began, though after he understood the source of his ill-health, I have no doubt that the “nocebo” effect may have added to his stress, adding insult to injury. He has since abandoned that home, and is once again sleeping soundly and feeling well.

The current sound standards, based as they are on dBA weighted acoustic measurements, gives particular weight to audible frequencies in the soundscape, but very little or no weight to low sound frequencies and infrasound, particularly below 10 Hz, which comprises a significant proportion of the sound generated by large turbines . People do not hear dBA, they hear qualitatively different sounds, birds, insects, running water, wind in the trees, etc. … basing noise criteria solely on this single number ignores the unique nature of the sound produced by large wind turbines, with its constantly changing loudness, frequency, harmonics, pitch, and impulsive quality. It is precisely these qualities that make the sound feel so intrusive and annoying, especially in quiet rural environments where these projects are usually located (12). Parenthetically, the word “annoying” is somewhat misleading, as it implies a minor, temporary, or occasional nuisance that perhaps might be mostly ignored, rather than what it is: a repetitive stressor that can degrade one’s short and long term health and well being, and from which there is no escape over the lifetime of the project short of having to abandon one’s home.

It is worth repeating here that the current Public Service Board threshold of 45 dBA of audible sound, averaged over an hour, has never been proven safe or protective, and that most studies agree that audible sound should not exceed 35 dBA, or 5dBA above normal background sound levels. (this is especially important in rural areas where background noise is minimal). The level should be a maximum , not an hourly average. Above 35 dBA there are likely to be significantly more complaints, particularly difficulty sleeping.


Before concluding, I would like to emphasize that the bulk of scientific evidence for adverse health effects due to industrial wind installations comes in the form of thousands of case reports like the patient I described. One or two sporadic anecdotal cases can legitimately be viewed with a wait-and-see skepticism, but not thousands where the symptoms are so similar, along with the ease of observing exposure and measuring outcomes, wherever these projects have been built. I agree with Epidemiologist Carl Phillips, who opined that “these case reports taken together offer the most compelling scientific evidence of serious harm. Just because the prevailing models have failed to explain observed adverse health effects does not mean they do not exist”, and, as he succinctly, though in my opinion a bit too harshly, concluded: “The attempts to deny the evidence cannot be seen as honest scientific disagreement and represent either gross incompetence or intentional bias” (13).

I am aware that the members of the PSB bear a heavy responsibility for Vermont’s overall energy future and have many other issues on their plate besides this one. Rather than presenting you with a long list of literature references most of which would likely go unread ( but they are included just in case ), I recommend a careful review of just one study in particular: Bob Thorne, a professional acoustician in Australia, presented an excellent and well thought out clinical study to the Australian Senate in 2011 (12). It really does cover the waterfront, including WHO quality of life measures, audible and infrasound measurements, and health measures, in a balanced and scientific way. For your convenience there is a hard copy of this study included with my presentation today.

His comprehensive ( including the full sound spectrum, not only dBA weighted sound ) and protective recommendations for sound criteria are reasonable, and if adopted, would be likely more acceptable to neighboring households and communities. However, given that wind developers are these days building bigger turbines atop taller towers in order to maximize power generation and profits, adoption of these safer limits would necessitate siting the installations farther from dwellings. A 1-2 km setback is not nearly sufficient; significant low frequency sound pressure measurements have been recorded in homes 3-6 miles from large projects in Australia.

The outcomes of the study are concerned with the potential for adverse health effects due to wind farm modified audible and low frequency sound and infrasound. The study confirms that the logging of sound levels without a detailed knowledge of what the sound levels relate to renders the data uncertain in nature and content. Observation is needed to confirm the character of the sound being recorded. Sound recordings are needed to confirm the character of the sound being recorded.
The measures of wind turbine noise exposure that the study has identified as being acoustical markers for excessive noise and known risk of serious harm to health (significant adverse health effects)
1. Criterion: An LAeq or ‘F’ sound level of 32 dB(A) or above over any 10 minute interval, outside;
2. Criterion: An LAeq or ‘F’ sound level of 22 dB(A) or above over any 10 minute interval inside a dwelling with windows open or closed.
3. Criterion: Measured sound levels shall not exhibit unreasonable or excessive modulation (‘fluctuation’).
4. Criterion: An audible sound level is modulating when measured by the A-weighted LAeq or ‘F’ time-weighting at 8 to 10 discrete samples/second and (a) the amplitude of peak to trough variation or (b) if the third octave or narrow band characteristics exhibit a peak to trough variation that exceeds the following criteria on a regularly varying basis: 2dB exceedance is negligible, 4dB exceedance is unreasonable and 6dB exceedance is excessive.
5. Criterion: A low frequency sound and infrasound is modulating when measured by the Z- weighted LZeq or ‘F’ time-weighting at 8 to 10 discrete samples/second and (a) the amplitude of peak to trough variation or (b) if the third octave or narrow band characteristics exhibit a peak to trough variation that exceeds the following criteria on a regularly varying basis: 2dB exceedance is negligible, 4dB exceedance is unreasonable and 6dB exceedance is excessive.
6. Definitions: ‘LAeq’ means the A-weighted equivalent-continuous sound pressure level [18]; ‘F’ time-weighting has the meaning under IEC 61672-1 and [18]; “regularly varying” is where the sound exceeds the criterion for 10% or more of the measurement time interval [18] of 10 minutes; and Z-weighting has the meaning under AS IEC 61672.1 with a lower limit of 0.5Hz.
7. Approval authorities and regulators should set wind farm noise compliance levels at least 5 dB(A) below the sound levels in criterion (1) and criterion (2) above. The compliance levels then become the criteria for unreasonable noise.
Measures (1-6) above are appropriate for a ‘noise’ assessment by visual display and level comparison. Investigation of health effects and the complex nature of wind turbine noise require the more detailed perceptual measures of sound character such as audibility, loudness, fluctuation strength, and dissonance.

To exclude careful independent well designed case studies like Thorne’s ( and others ) in a review of the scientific literature that purports to be thorough is, I repeat, a serious omission and is not “scientific”. Careful consideration of these independent well done studies, if nothing else, should encourage regulatory agencies to adopt a much more precautionary approach to the siting of today’s very big industrial wind projects in order to adequately protect public health. For better or worse, in today’s “information age” we are perhaps too fascinated by computers and mountains of data, but truth is truth, wherever you find it, even in small places.

Thank you very much for taking the time to address this issue, and for listening.

Respectfully Submitted,


Many thanks to Sarah Laurie, CEO of the Waubra Foundation, for her tireless work, and generosity in sharing so much information.

1. Pierpont, Nina. 2009. From the executive summary of her peer reviewed study.
2. Capuccio et al. 2011. Sleep Duration predicts cardiovascular outcomes: a systemic review and meta-analysis of prospective studies. European Heart Journal 32:1484-1492.
3. Nissenbaum, M, Hanning, C, and Aramini, J. 2012. Effects of industrial wind turbines on sleep and health. Noise and Health, October.
4. Shepherd, D, et al. 2011. Evaluating the impact of wind turbine noise on health related quality of life. Noise and Health, October.
5. Arra, M, and Lynn, Hazel. 2013. Powerpoint presentation to the Grey Bruce Health Unit, Ontario: Association between wind turbine noise and human distress.
6. Kelley, ND, et al. 1985. Acoustic noise associated with Mod 1 turbine, its impact and control.
7. James, Richard. 2012. Wind turbine infra and low frequency sound: warning signs that went unheard. Bulletin of Science, Technology and Society 32(2):108-127, accessed via Professor Colin Hansen’s submission to the Australian Federal Senate Inquiry Excessive Noise from Windfarms Bill (Renewable Energy Act) November 2012 James references another useful bibliography of references of the early NASA research, compiled by Hubbard & Shepherd, 1988: Wind turbine acoustic research—bibliography with selected annotation;
8. Hubbard, H. 1982. Noise induced house vibrations and human perception. house vibrations-human-perception/
9. Ambrose, Stephen, and Rand, Robert. 2011. Bruce McPherson infrasound and low frequency noise study.
10. Schomer, Paul, et al. 2013. A proposed theory to explain some adverse physiological effects of the infrasonic emissions at some wind farm sites.
12. Also see: Thorne, Bob. 2011. The Problems With “Noise Numbers” for Wind Farm Noise Assessment.
 Bulletin of Science, Technology and Society 31:262. 
DOI: 10.1177/0270467611412557.
13. Phillips, Carl. 2011. Properly interpreting the Epidemiological evidence about the health effects of Industrial Wind turbines on nearby residents. Bulletin of Science, Technology and Society vol 31 No 4 (August 2011) pp 303-315.

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