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Health and safety concerns:
The information on this page is based on the report prepared for CREB by the health and safety subcommittee. Pursuant to the committee’s own search for information and that of other citizens, this subcommittee, which was open to the public for membership, formed in July and issued its report on August 15, 2008. The report reflects the best efforts of the subcommittee to develop, in a short period of time, an informational document, reflecting a neutral point of view, the current domain of knowledge on health and safety.
The report is now available online at http://www.barringtonenergy.com/wind_energy_project/reports |
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Structural Failure
Although wind turbine structural failures have occurred, most commonly in the form of blade failures, to date all but one of the documented injuries from wind turbines have been associated with accidents involving wind industry workers and not structural failure.Based on a nationally accepted approach, it is estimated that a person who remains all year long at a distance of just under 900 ft from the turbine has a probability of being hit by a blade tip fragment of about 4 in 10 million, roughly the same as being hit by lightning.
The probability of failure of a new turbine can be lowered by dealing with reliable manufacturers and contractors and following good maintenance and operational practices.
Noise
When operating, the blades of a Wind Turbine Generator (WTG) make a rhythmic "swishing" sound. Response to this noise is subjective. The following table compares the estimated noise levels at various locations and conditions from a WTG (the size of the one being considerd for Barrington) to noise standards. These standards have been established by the World Health Organization and the American National Standards Institute.
| Estimated WTG Sound Level | Standard Sound Limit - Day | Standard Sound Limit - Night | |
| Building at 200 ft - Outdoors | 53 dB | 55 dB | 45 dB |
| Building at 200 ft - Indoors, Window Open | 36 dB | 35 dB (classroom) | 35 dB (classroom) |
| Building at 200 ft - Indoors, Window Closed | 26 dB | 35 dB (classroom) | 35 dB (classroom) |
| Dwelling at 500 ft - Outdoors | 47 dB | 55 dB | 45 dB |
| Dwelling at 500 ft - Indoors, Window Open | 30 dB | N/A | 30 dB |
| Dwelling at 500 ft - Indoors, Window Closed | 20 dB | N/A | 30 dB |
| Dwelling at 1,000 ft - Outdoors | 41 dB | 55 dB | 45 dB |
| Dwelling at 1,000 ft - Indoors, Window Open | 24 dB | N/A | 30 dB |
| Dwelling at 1,000 ft - Indoors, Window Closed | 14 dB | N/A | 30 dB |
For purposes of comparison, 60 dB is approximately the sound level of ordinary conversation in an otherwise quiet living room, and 40 dB a soft whisper 6 ft away in a library.
Icing
On average in Rhode Island, there have been 0.6 ice storms per year since 2000. Icing of a Wind Turbine Generator (WTG) can be a hazard if fragments fall off or are thrown. Since 1975, there have been 23 incidents of ice fall or ice throw anywhere in the world, with only one case resulting in human injury. However, mitigating actions can be taken to minimize any probability of injury.The greater potential danger is for ice throw from an operating WTG – ice thrown by the moving blades. Modern WTG’s have safety controls designed to shut down the turbine when a ice conditions exist. WTG's can also be manually shut down. In the unlikely condition of ice on an operating WTG, studies of actual incidents have shown that ice throw fragments from rotors are primarily in the range of 3 oz to 2.2 lbs and fall mostly within 50 to 330 ft of the turbine.
Ice fall from a stationary WTG is also a concern, but the risk of danger from ice falling from the wind turbine under these conditions is comparable to the risk of ice falling from any other tall structure (e.g. light tower or cell tower).
An industry rule-of-thumb suggests a setback of 730 ft for both ice falls and ice throw for the size of turbine being considered for Barrington.
Shadow flicker and lighting effects
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| Shadow Flicker Areas |
Locations outside the 12 hour area can experience some flicker. This flicker would only occur when the WTG is operating on bright sunny days at locations where the WTG can be seen. At most, flicker would occur over a period of about a month (near the respective solstice) for about 20 minutes per day at 1,000 ft from the WTG and 10 minutes perday at 2,000 ft.
The impact of flicker on residences can be minimized through control strategies such as evergreen tree plantings.
Wildlife Impacts
Bird mortality in the eastern U.S. averages about 4 birds per turbine per year, based on studies conducted at wind farms in Tennessee and West Virginia. The number of birds killed by wind turbines is much lower than by these other sources, particularly collisions with buildings and high tension wires. This would remain true even if wind energy saturated the U.S. market. Developing post-construction monitoring protocols to survey the presence of wildlife species and the incidence of any wildlife mortality as a result of the wind turbine can aid in determining whether mitigation strategies would be needed, such as discouraging roosting or nesting, adjusting FAA warning lights, and collecting ~3 years of monitoring data.A particular issue for Brickyard Pond is that it is in a waterfowl migratory flyzone. Birds that are part of the Brickyard Pond waterfowl migratory flyzone include: egrets, ospreys, blue and white herons, cormorants, canada geese, swans, red tailed hawks, and assorted ducks.