Rural System's

The Soundscape Group (Earshot)

The progress of a race in civilization may be marked by a steady reduction in the volumn of sound which it produces. The more culture of all kinds it acquires, the less noise it produces.
E.L. Godkin, founder of The Nation magazine

Thomas Edison once predicted American city dwellers all would be deaf.

Raymond W. Smilor (author of "Hearing History") served as an officer of the Society for the Supression of Unnecessary Noise. Under growing pressure from citizen's groups, some cities regulate train whistles, roosters, hawking peddlars, auctions, fireworks, and nighttime music, and created quiet zones around hospitals, schools, assisted living, and other places.

There are well known landscapes, but few people have heard of soundscapes. They become more important each day as trying to find a quiet place to work, think, meditate or live a stress-reduced life becomes more difficult.

The Soundscape Group or Earshot includes work with Nature Folks and trying to listen for the sounds of nature such as the calls of birds and particularly the night sounds of amphibians. It forms a paying membership, issues a newsletter, sells equipment, sells tours, and provides services for industry certifying certain noise lavels and changes resulting from management, private groups promoting a more quiet space, and sales of services for quieting situations (such as buildings, dogs, individuals, and equipment.) It utilizes research on noise attenuation resulting from vegetation. See the list of potential activities below and Noise notes within The Trevey.

Giles once tried to capture the sounds of a forest and to see if a difference could be detected before and after a pesticide application. (It could not with the instrumentation available to him at the time.)

The GIS can be used to analyze gun shots to assist in law violation detection. The hunted zone and its gun noises (randomly distributed gunners) might be mapped for general interest. Locating houses and recreational sites can be done with noise sources in mind and measures (or topography) selected to reduce effects of noise on people. Whether new noise from a proposed development is the subject of great interest as impacts are studied.

The company may be able to be profitable from a series of activities:

1. Measuring sound levels for a price
2. Recommending noise reductions strategies
3. Commissioning hearing tests and therapy
4. Publishing books
5. Developing GIS maps for industries etc.
6. Testifying about the impacts of proposed developments on nursing homes, hospitals, residences, etc.
7. Documenting a baseline of noise and issuing an annual report of the change from the base
8. Advising on vegetation (or its removal) as it may affect noise
9. Reporting on the effects of specimen trees and wildlife trees and shrubs on sounds and noise levels
10. Working with home builders to seek improved life quality for residents as related to interior sounds
11. Seeking grants to monitor a sample of local people as a hearing baseline.
12. Selling booklets and magazine articles describing sounds, noises, noise abatement and health relations
13. Converting sound levels to color and creating soundscape maps
14. Promoting ear and noise protection
15. Selling hearing -protection devices

Noise Abatement

Noise from airports, highways, and industrial development ... even recreational area use may increase. A noise abatement program (study, with implementation) can be preventive and help in achieving desired conditions for people and wildlife.

One performance measure for overall FAA system success included in FAA planning documents is to count and report the number of homes and public buildings exposed to greater than a 65 Day-Night Level (DNL) in areas adjacent to airports.The number should be stable or decreasing.

A noise abatement program is likely to be a complex system with many objectives or goals and have more than the following expanded elements :

• Aircraft
  • Promotion of use of quiet craft (high bypass ratios and low velocity jets)
  • Limitations on landing of recognizably noisy craft
  • Require acoustically treated nacelles and ducts of locally housed and high-use craft
  • Require noise suppression for on-board auxiliary power units
  • Promote improved rotor and propeller aerodynamics for local craft
  • Require noise suppression for mechanical components (e.g., helicopter gear boxes)
  • Tax rate differentials for craft with high noise production (e.g., encouraging steeper ascent and descent or reduced time for these operations (See US DOT P5630.1 Transportation Noise and its Control)
• Operations
  • Restrict operations by type of craft
  • Restrict operations by number of operations
  • Restrict operations by time of day and special days (e.g., holidays)
  • Require power cutback on takeoff or steep climb-out depending on situation
  • Require steep or multi-segment approach depending on flight conditions
  • Require landing far from terminal, then taxi to terminal
  • Require warmup tests be conducted far from the terminal within a noise buffered space
• Maintenance
  • Restrict engine "run-ups" during ground maintenance operations
  • Maintain additional hardware for noise suppression (e.g., treated nacelles or auxiliary power-unit silencers)
• Route Location
  • Demark routes on the ground to avoid overflight
  • Avoid noise sensitive areas (select school, recital buildings, etc.)
  • Use noise insensitive areas for ascent and descent paths
• Landscape Architecture
  • Acknowledge that environmental noise has a significant effect on the quality of life, even when the noise is not severe enough to induce medical of psychological symptoms in the people exposed to it.
  • Shield airport surroundings from noise resulting from aircraft ground operations and surface vehicle operations
  • Create wide planted strips as near the noise source as possible. A soft "forest" floor reduces the intensity of low frequency sounds. Leaves and stems help reduce noise levels by scattering high frequency sound waves. More than a few rows of trees are needed to substantially reduce noise pollution. They must be deciduous near the noise source, evergreen away from it, and in dense stands 16 feet wide. If wide strips are impossible, then constructed barriers with beautifications can be used to provide noise relief. However, constructed barriers, poorly planned, can increase noise levels. Trees at the crest of earthen barriers may scatter high frequency sounds down into the protected area behind the barrier.
  • Assemble effects of noise stress on human and livestock health.
  • Integrate development of land developments with airport noise abatement. D.I. Cook and D.F. VanHaverbeke (another paper cited later) recommend (J. Soil and Water Cons Nov Dec 1972, p 259-261) planting 20-50 ft wide belts of trees and shrubs with the nearest edge of the belt within 20-50 feet from the center of the nearest traffic lane. Shrubs should be placed closest to the airport with backup rows of taller trees. They recommended evergreens for year around screening. A land form of 6-8 feet height was suggested for auto traffic buffering. It should be planted with dense shrubs in the front border to form a composite structure with a total height of at least 20 feet. A soft undersurface throughout the area was recommended to reduce reflected noise.
  • Set in motion a series of tree and shrub replacements (e.g., from a specific nursery) as the plants age, change shape, and their noise-control effects change.
  • Acknowledge that perception of noise and the evaluation of noise is psychological and can be influenced just as can the noise sources. Intensive study of research reports is needed for findings are counterintuitive, For example, perceived loudness of sounds tended to increase as the amount of vegetation visible in the sites increased. Perceptions of noise are related to past experience expectations and visual cues. There is an interaction between acoustic and other features of the environment that modifies the effect of different sounds. Noise is unwanted sound and thus it has personal dimensions. There can be group decisions about what is "unwanted".

    Rate citizen perception of noise to establish a base line and evaluate changes in it over time resulting from changes in noise sources and efforts to influence landscape architecture, insulations, etc. Anderson et al. found jets passing overhead had a noise rating of 3.4 (a scale of 1 as most detracting to 8 most enhancing). Jets taxiing and takeoff had a rating of 2.8. Songbirds were rated 6.5. Use recent research on heart stress from noise to establish recommendations.

    The cost of lowering noise levels is great, but so too is noise threat to public health, welfare, and the quality of life in the neighborhood and Town. Citizens in cooperation with airport (and other developments) and law enforcement groups need to work to avoid exceeding Aircraft noise standards, both Composite Noise Ratings (CNR) and NEF (Noise Exposure Forecast). Work with the policies and concepts of J.F. Miller ( formerly Director, Division of Environmental Planning, HUD and Clarence F. Nelson, Env. Clearance Officer, HUD, 701 E. Franklin St., Richmond, Va 23219 in the 1970s) seems reasonable. Paradis, R.F. (NTIS AD-A054 182 - Dollars per decibel, a common sense approach to evaluating noise reduction alternatives, Naval Facilities Engineering Command, Norfolk) seems a useful guide for cost control.

  • Acoustic Insulation
    • Modify building codes so that all construction within the high aircraft noise contours must include noise insulation
    • Provide barriers in areas for aircraft run-ups
    • Add protection to schools and public buildings
    • Develop incentive programs (financial etc.) for home owners to add insulation.
    • Provide information to citizens on best current materials and practices for noise insulation
  • Land Use Restrictions
    • Rezone areas within the noise contours of the airport, giving additional restrictions to the conventional zone designations
    • Clarify and publish HUD and other federal and state laws related to loans possible within noise zones.
    • Publish summaries and abstracts of current studies on the effects of noise pollution on relevant human and livestock health.

  Photoacoustics

  In recent years (1981) the photoacoustic effect has evolved as an extremely powerful tool for probing either the thermal properties or the optical properties of solids. In a typical photoacoustic experiment, the sample under investigation is placed inside a closed cell containing a gas, such as air, and a sensitive microphone. A chopped light beam from an external lamp is transmitted through a window in the cell and focused on the sample. Upon absorbing the chopped light, the temperatures of both the sample and surrounding gas rise and fall with the same frequency as the modulated light. The resulting variations in the gas pressure are monitored by the microphone, the output voltage of which is called the photoacoustic signal. The signal results from optical absorption measurements. It is especially useful on opaque substances (and suggested here for soils work in the Inquire Lab). There are basically three important lengths in any photoacoustic experiment (L) the sample thickness, (L₀) the optical absorption length which equals the reciprocal of the optical absorption coefficient, and (L_s) the thermal diffusion length. The latter two lengths measure distances over which the light intensity and sample temperatures decrease exponentially from their values at the surface. All of these lengths are unique properties of the sample. Optical transmission and reflectance measurements determine the optical absorption length L₀. The photoacoustic effect can determine L₀ and L_s, the latter being a thermal property of the sample.

  The enterprise suggested herein is resigned for people interested in sounds and noise, all types. Designing recreational areas (see BASIC units of Giles), evaluating and mapping the quiet zones of wildernesses and parks, working with military and law enforcement groups, and even working at the sub-molecular level are all challenges that can be mastered by experts in this one type of energy.

  Marketing can be through simple noise makers and demonstrations. Public health professionals will surely cooperate.

  See Joslin and Youmans. 1999. Effects of recreation on Rocky Mountain wildlife: A Review for Montana. Montana Chapter of The Wildlife Society. 307pp.

  Hard copy can be tracked down by email gjoslin@state.mt.us Free copy on the web at www.montanatws.org All the literature you had no idea existed, plus a whole lot more. (note from Jack Lyon, 2/2003)

  See Trevey unit on noise.

  References

  Anderson, L.M., B.E. Mulligan, and L.S. Goodman. 1984. Effects of vegetation on human response to sound, J. Arboriculture 10(2):45-49

  Anderson,L.M. , B.E. Mulligan, L.S. Goodman, and H.Z. Regen. Effects of sound on preferences for outdoor settings. Environemnt and Behavior 15(5):539-566.

  Cook, D.I. and D.F. VanHaverbeke. 1977. Surban noise control with plant materials and solid barriers, Res. Bul. EM 100, Rocky Mt. Forest and Range Exp. Sta., and Univ. Nebraska, Lincoln, 74pp.

  Johnson, K., R Zitter, K. Telschow, October, 1981The photoacoustic respopnse of coal. Mineral Matters (Southern Ill. Univ. at Carbondale, Carbondale, Il 62901, p.1.

  Joslin and Youmans. 1999. Effects of recreation on Rocky Mountain wildlife: A Review for Montana. Montana Chapter of The Wildlife Society. 307pp.

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  Network potential (email Feb, 2003) Subject: Noise Impacts and Wading birds, shorebirds, and other water birds

  I'm wondering if anyone has any recent guidelines or information addressing the issue of noise impacts to shorebirds, wading birds, or other water birds.I also would be interested in how others have addressed fragmentation, roadway mortality and the whole host of other impacts (secondary and cumulative) associated with major highways.

  Judith S. Smith
  Reynolds, Smith, and Hills, Inc.
  1715 N. Westshore Blvd., Ste 500
  Tampa, Florida 33607
  813.289.5550
  judy.smith@rsandh.com
  
  

  Perhaps you will share ideas with me about some of the topic(s) above .
  

  

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  Robert H. Giles, Jr.
  July 2, 2005