Showing papers on "Noise pollution published in 1986"

Ambient noise in the sea

Abstract: : By ambient noise we mean the prevailing, sustained unwanted background of sound at some spot in the ocean. It excludes momentary, occasional sounds, such as the noise of a close-by passage of a ship or of an occasional rain squall. It is the background of noise, typical of the location and depth where a measuring hydrophone is located, against which a signal," such as the sound of a submarine or the echo from a target, must be detected. Ambient noise also excludes all forms of self-noise, such as the noise of current flow around the measurement hydrophone and its supporting structure, and obviously must exclude all forms of electrical noise. Thus, ambient noise is what is left over, so to speak, after identifiable, occasional noise sources are accounted for.

The relative effect of noise at different times of day: An analysis of existing survey data

Abstract: This report examines survey evidence on the relative impact of noise at different times of day and assesses the survey methodology which produces that evidence. Analyses of the regression of overall (24-hour) annoyance on noise levels in different time periods can provide direct estimates of the value of the parameters in human reaction models which are used in environmental noise indices such as LDN and CNEL. In this report these analyses are based on the original computer tapes containing the responses of 22,000 respondents from ten studies of response to noise in residential areas. The estimates derived from these analyses are found to be so inaccurate that they do not provide useful information for policy or scientific purposes. The possibility that the type of questionnaire item could be biasing the estimates of the time-of-day weightings is considered but not supported by the data. Two alternatives to the conventional noise reaction model (adjusted energy model) are considered but not supported by the data.

Noise pollution: Effects and control

Abstract: FUNDAMENTALS OF NOISE AND HEARING: Introduction: Noise Pollution, Man and Sound Physics of Noise Review of Noise Propagation in the Atmosphere Aural Reception Recent Advances in Understanding Hearing Mechanisms and Hearing Impairment Psychophysics of Hearing EFFECTS OF NOISE ON MAN: Auditory After-effects of Noise Non-auditory Effects of Noise: Physiological and Psychological Effects Noise Interference with Oral Communication Noise Pollution during the Night: A Possible Risk Factor for Health Hearing Conservation SOURCES OF NOISE AND ITS CONTROL: Road Traffic: Generation, Propagation and Control Aircraft Noise Generation and Control: Noise Around Airports Acoustic Shielding: Noise Reduction by Thin and Wide Barriers Solid-borne Noise Control in Buildings and Machinery Impact Machinery Noise: Prediction and Control Building Noise Control: The Main Problems, Available Technology and Future Trends Noise Pollution Control: Present Possibilities of Controlling Noise Inside Buildings Juridicial and Legal Aspects of Noise Control Epilogue.

Airport Noise Control Strategies

Abstract: : The Federal Aviation Administration's (FAA) Airport Noise Control Strategies Data File contains a comprehensive listing of airport noise control actions. The information contained in this data file is an updated version of the June 1983 Airport Noise Control Strategies report. Originally, the data were collected from the Environmental Data Bank of March 1979, the National Business Aircraft Association and the Aircraft Operators Council International. Additional data were garnered from the FAA Airport Facility Directory. For this version, the FAA regional offices reviewed the latest information and made appropriate changes. Thirty-seven categories of noise control actions have been identified and are in use, singly or in combination, by approximately 400 airports.

Air-quality and noise issues in environmental planning

Abstract: The 9 papers in the report deal with the following areas: some recent developments in traffic flow and air quality in a mountain community; evaluation of the CALINE line source dispersion model for complex terrain application; tunnel portal noise; traffic-related noise as a factor in eminent-domain proceedings in Florida; analyzing construction noise by a level/duration; noise-emission levels for vehicles in Ontario; heavy-truck noise-emission levels on grades in California; a methodology for assessing highway-traffic-noise impacts in an airport environment; considerations for modeling of aircraft noise.

Wind‐energy farm noise impacts on nearby residences—the citizen's view

Abstract: Wind‐energy farms, with hundreds of wind turbines, have proliferated in close proximity to residential properties, without any apparent control on the noise impact consequences. Annoying and intrusive wind turbine noise occurred as soon as the first turbines were installed. The adverse noise impact has continued and intensified as additional WECS (wind energy conversion system) sites were approved and developed with the installation of hundreds of additional turbines. The adverse noise effects consist of low‐frequency noise that is not fully addressed or controlled by only A‐weighted sound level standards, pure tones, and higher noise levels during higher wind‐speed conditions. More stringent noise controls should have been implemented in the beginning. Riverside County has recently adopted a more stringent noise standard that also includes a pure tone restriction that will apply to future sites. However, mitigation of the mistakes made at the earlier sites remains to be resolved.

Evaluation of Noise Level of Steel Railway Bridges

Abstract: The results of experimental research on steel railway bridge noise and of an attempt to evaluate its loudness and frequency, as well as the influence of certain factors connected with communication...

Community response to noise in Australia: results of the 1986 national noise survey

Abstract: A social survey was carried out in February 1986 to assess the extent of community noise disturbance in Australia. A total of 2,332 people were interviewed in all federal electoral divisions. The results indicate that noise is the most serious form of environmental pollution experienced by residents. The rank order of neighbourhood problems which respondents were either concerned about or affected by is: 1) noise disturbance; 2) unpleasant odours, smoke or dust; 3) poor tasting water; and 4) spilled garbage or litter. The survey also assessed the relative disturbance caused by various types of noise pollution using a number of different indicators of reaction. The noises which have the greatest impact on residential communities were found to be traffic and barking dogs. Twenty per cent of Australian residents experience at least moderate annoyance because of each of these two noise sources. Overall, 40 per cent of Australians experience disturbance to listening activities or to sleep because of some form of noise pollution. The most commonly reported causes of annoyance from individual motor vehicles in all states are hotted up cars and motorbikes. The survey confirmed that complaint data is a poor indicator of the community impact of noise. Also, reaction to noise was found to decrease with age but to increase with education level. The present survey provides a baseline for future monitoring of the effectiveness of national noise control strategies in Australia (a).

Overtaking warning indictor for vehicle

Abstract: The utility model relates to an overtaking warning signal device for motor vehicles. A loudspeaker and a lamp are generally adopted to warn and overtake by the present motor vehicles. The warning purpose is seldom obtained under the influence of external factor, and furthermore, the warning of the loudspeaker increases the noise pollution of cities. The utility model adopts the technology of radio remote, centralizes transmitting, receiving and action indication into the same motor vehicle and shares the same antenna. The overtaking warning signal device for motor vehicles has the advantages of wide carrier frequency, narrow modulating frequency, less power consumption, safety, reliability, no noise pollution, etc. The utility model can be safely used on motor vehicles running on highways and can be made into a pocket type machine for people to use.

Saudi Petrochemical Plant Noise Control

Abstract: The Kingdom of Saudi Arabia is constructing a highly industrialized city, Madinat Al-Jubail Al-Sinaiyah, in its Eastern Province. This city is a cornerstone of the Saudi Arabian goal for a self-sufficient industrial state. Fluor Technical Services, Ltd., was selected as Managing Contractor and Constructor, and three other companies were selected as Process Contractors for the design and procurement of a sophisticated multibillion dollar petrochemical complex in this industrial city. The objectives of the noise control design for this project were to ensure compliance with the occupational noise limit of 85 dBA and property line noise limit of 75 dBA. Comprehensive technical and cost analyses were performed to ensure that the most feasible and econommical noise mitigation methods were used for this complex. Computer noise contour analyses were performed for the overall plant and for each process area to verify compliance with in-plant and property line noise criteria. According to the noise contour analysis, acoustic treatment measures implemented for this complex were very effective.