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EDs are noisy and the noise levels exceed regulatory recommendations. Noise distracts us during any task and can saturate our attentional demand and impair our thinking and decision-making. This is a systematic problem that is consistently ignored by accreditation bodies. Many of our patients are vulnerable to the adverse impact of noise including the elderly, people with mental health problems, migraine and those with sensory impairments. Our noise levels are equivalent to a noisy restaurant. When noise levels are reduced, staff report less stress and better work conditions. Noise is a patient safety issue, as excessive noise impairs good communication, which is essential for patient care. Good acoustic design and management is achievable, but needs to be explicitly assessed as a part of accreditation standards. This would promote wellness for both patients and staff.

The first objective of the acoustical design of rolling stock vehicles is the compromise between passenger comfort and the technical and economical means required to achieve it. Typically, global A-weighted sound pressure levels are used to evaluate acoustical such performance, but acoustical comfort is a complex phenomenon and it is difficult to find a single measure that fits all situations. This paper presents a novel approach to the study of one such special case: comfort experienced by passengers engaged in telephone conversations in a train. Noise inside the vehicle will affect the comfort of the telephone conversation, but we found a better measure of comfort than global dB(A) levels. Its definition, based on 1/3 octave band spectra, can be used since the beginning of the design of a new rolling stock to drive the acoustical design of passenger areas, including vestibules.

The great Greek Amphitheatre at Epidaurus is known the world over for its exceptional acoustics. It is an extraordinary piece of sonic architecture. Its location, nestled into the hills and facing away from the city, would have been very effective at limiting the amount of noise intruding into the venue. If spaces were scaled with acoustic functionality in mind they would commonly be smaller volumetrically than visual aesthetics would dictate, thus requiring fewer additional acoustic ‘treatments’ overall. Acoustics should not necessarily be uniform in the built environment. Spaces should be designed with unique, delightful, bespoke acoustics. Good acoustic design can create transition moments. It can be exceptionally useful at transitions to accent, enhance and ignite architectural experiences. It can be used to guide and lead people through buildings and spaces.

The low noise design must be embedded in every design phase of the train vehicles. The vehicle noise calculation models are established by taking full account of vehicle geometrical dimensions, measuring point location, noise sources, sound insulation and sound absorption. These models can (1) complete quantitative assessment of acoustic structures and noise sources of the vehicles to achieve the top-down quantitative control of acoustic index; (2) calculate interior noise and exterior noise under static conditions, running conditions, as well as tunnel environment conditions; (3) calculate and analyze noise limit values of main noise sources when the sound insulation of walls have been given, such as floor, side wall and gangway; and (4) calculate and analyze sound insulation limit values when the sound power of main noise sources have been given. The average differences between the A-weighted measured and predicted levels are less than 2 dB. The models show a very important guiding role for quantitative acoustics design of metro trains.

The paper describes how was measured the noise level at the facade of a multilevel residential building from the city of Cluj-Napoca, Romania. The building has two sides parallel to the railway situated at a distance of about 20 m from it. Because of the small distance the noise level produced by the trains is much over the admitted limit at the building’s facade and therefore it was necessary to design a noise protection barrier between the building and the double railway to fully meet the fundamental requirement applicable to constructions “insulation to noise”. The aim of the acoustic design presented in the paper was to ensure that the noise level measured at 2 m from the building facade respect the noise design standards from Romania, which are in full agreement with the European norms.

Due to the need for an ocean voyage, the shape and material of pressure-resistant structures of submersibles need to meet higher requirements. At present, the static mechanical properties of pressure-resistant systems have been extensively studied. However, it is still necessary to further explore its acoustic radiation noise to provide a reference for the overall acoustic design. A combination of the finite element method and wave superposition method (FEM-WSM) is used to calculate the acoustic radiation field of axisymmetric pressure-resistant structures in the ocean environment. Taking spherical, egg-shaped, and multi-body egg-shaped shells as examples, explores the distribution of acoustic radiation field of axisymmetric pressure-resistant shells under different shapes, materials, and submerging depths.

This paper analyses the acoustic conditions inside two lecture rooms in faculty of agriculture, Cairo University, based on field measurements and simulation technique. Ambient noise and reverberation time were measured in the unoccupied rooms. The measurement results were utilized for validating the results of CATT software that was used to estimate occupied reverberation time, STI and C 50 . These parameters were analysed in comparison with rooms’ properties, optimal reverberation time and maximum acceptable noise for learning spaces. The results demonstrated that acoustic design of the first room is far from the recommended values, whereas the second room includes many defects. For optimizing the rooms’ performance, acoustic treatments were proposed and explored. Results clarified that reducing the excessive reverberation to the optimal value, either by increasing room absorption or decreasing room volume, significantly optimizes speech intelligibility. The results also clarified that reforming the ceiling eliminated the shadow and increased the early reflections.

Raymond murray schafer’s acoustic ecologist vocabulary, goals and tactics have recently been taken up by european noise abatement societies. Yet how does this relate to their more traditional noise abatement strategies? and what might be behind it? this chapter answers these questions by analyzing the websites and publications of three major european noise abatement societies: the uk noise abatement society (nas), the dutch society against noise nuisance (nsg) and the working group on noise of the german acoustical society (ald). The author suggests we can harvest the increasing interest of noise abatement societies in schafer’s legacy by linking schafer’s widely cited ideal of the soniferous garden, to local ordinances—in eardonances that entitle urban citizens to the use of acoustically secluded and enriched spaces.keywordsnoise abatementeuropean historyacoustic ecologyacoustic design.

The indoor-outdoor connection provided by ventilation openings has been so far a limiting factor in the use of natural ventilation (NV), due to the apparent conflict between ventilation needs and the intrusion of external noise. This limiting factor impedes naturally ventilated buildings meeting the acoustic criteria set by standards and rating protocols, which are reviewed in this paper for residential buildings. The criteria reflect a general effort to minimize noise annoyance by reducing indoor sound levels, typically without a distinction based on a ventilation strategy. Research has developed a number of solutions, discussed here, that try to guarantee ventilation without compromising façade noise insulation, but, currently, none have been adopted on a large scale. This concept paper highlights the main limits of the current approach. First, a fragmented view towards indoor environmental quality has not included consideration of the following acoustic criteria: (i) how buildings are designed and operated to meet multiple needs other than acoustical ones (e.g., ventilation, visual, and cooling needs) and (ii) how people respond to multiple simultaneous environmental factors. Secondly, the lack of a perceptual perspective has led acoustic criteria to neglect the multiple cognitive and behavioral factors impinging on comfort in naturally ventilated houses. Indeed, factors such as the connection with the outside and the sense of control over one’s environment may induce “adaptive acoustic comfort” opportunities that are worth investigating. The mere use of different sound level limits would not be enough to define criteria tailored to the complex user–building interaction that occurs under NV conditions. More holistic and human-centered approaches are required to guarantee not only neutrally but even positively perceived indoor acoustic environments. For this reason, this paper considers this apparent conflict from a soundscape viewpoint, in order to expose still unexplored lines of research. By underpinning a perceptual perspective and by contextualizing it, the indoor soundscape approach provides a framework capable of overcoming the limits of the traditional noise control approach. This could provide the opportunity to foster a wider adoption of NV as a passive design strategy that enhances user health and well-being, while enabling low-cost, and low-energy cooling and ventilation, thereby contributing to current climate change challenges.

The control of flow noise is an important design aspect nowadays in the HVAC industry. However, acoustic design has largely been based on trial and error, which leaves the physical mechanisms respo...

Detecting and selecting sound events is emerging as an interesting technique for characterizing and representing the sound environment of a specific location. In this article we propose a computational model for automatically constructing a so-called acoustic summary, i.e. a comprehensive collection of sounds aiming to represent the specific sound environment at a given location. Such an acoustic summary could be used by architects, soundscape designers, and urban planners to explore – by listening – the sonic environment at a certain location as it is perceived by a human listener. The model is based on a self-organizing map, a type of neural network. It starts by extracting several psychoacoustic features from the sound. A specific, extensive and unsupervised training allows this map to be tuned to the typical sounds that are likely to be heard at the microphone location. The learning algorithm takes into account some basic aspects of human perception. For example, salient events tend to be better remembered than the ones that do not stand out, even if they occur less frequently. After the training, the self-organizing map is used to form an exhaustive acoustic summary by means of automatically recording specific sound events for the microphone location. In addition to describing the proposed tool, this paper also presents a validation test with local residents in order to show the ability of the model to pick up sounds which bring out the distinctiveness and the specificity of the soundscape as a local resident would do.

Absorbing materials are fundamental for the acoustic design of buildings. They are used for increasing the insulation from either outdoor or neighbour noise and for raising the acoustic comfort of dwellings. If environmental and health issues are not of concern, conventional sound absorbers, namely synthetic foams and fibrous materials, offer an excellent acoustical performance at a moderate cost. However, the current trend towards eco-efficient products encourages the enhanced use of natural fibre and loose granular recycled materials. Whatever the material type, a model is required to reliably predict its acoustical performance. The microstructural Champoux–Stinson model has demonstrated to provide consistent acoustical predictions once five non-acoustical parameters are given. Instead of measuring these non-acoustical parameters, which is a rather sophisticated and time consuming procedure, an inverse method, based on Simulated Annealing, is proposed in this paper to estimate them from a single and simple measurement of the absorption coefficient. Experimental results on two samples of loose aquarium gravel validate the proposed inverse method.

Vehicle noise is one of the main sources of complaints because it is widespread and active in almost all environments, from urban areas to rural context. The present work aims to describe a practical procedure to design silencers for off-road motorcycles so that, once produced, they are lightweight, do not affect the engine performances and cut noise emissions to a sustainable limit. The required noise reduction, usually around 35–40 dB, can be achieved only by carefully designing the exhaust system. The first part of the paper provides the theoretical background of noise propagation in ducts, describes the main attenuation devices as tools the designer can use in the development process and outlines the workflow. In the second part, a case study of silencer optimization is presented: the noise emitted by a real off-road motorcycle is characterized and, once the sound pressure level and the mass flow generated by the engine are known, a silencer fulfilling noise attenuation, size and pressure drop requirements is designed, 3D-modeled and rendered. The outcome of the acoustic design process can be used to perform virtual sound quality tests, which can be of interest for manufacturers to catch the attention of passionate users.

Buller är en av de miljöföroreningar som har störst negativ påverkan på männi-skors hälsa. Några av dessa effekter är sömnstörningar, stress och i vissa fall kan detleda till hjärt- och kärlsjukdomar. Problematiken kring detta växer med en ökandebefolkningsmängd och urbanisering runt om i världen. Denna studie undersöker möj-ligheterna till att utveckla en ny ljudanalysmetodik för hållbara stadsmiljöer. Idag utförs trafikbullerutredningar som en del i miljökonsekvensbeskrivningar. Dessaanalyser innehåller i huvudsak en ljudnivåberäkning från de primära bullerkällornaoch dessa kopplas till gällande riktvärden för A-vägda ljudnivåer vid uteplatser ochfasader. Forskning kring urbana ljudmiljöer visar att endast ljudnivåerna från buller-källor inte är tillräckligt för att avgöra ljudkvaliteten. Bullrets relativa inblandning iljudmiljön, dess frekvensområde och tidsvariation samt platsens syfte och användningär faktorer som dels är kopplade till hur pass väl bullret maskeras, och dels hur passstörande ljudet faktiskt upplevs. Alla dessa faktorer behöver vägas in för att på bästasätt kunna bedöma ljudkvaliteten. Strategin som användes i denna studie bestod dels av en litteraturstudie där till-gänglig forskning kring urbana ljudmiljöer analyserades och dels i en fallstudie därtre olika typfall av urbana miljöer modellerades i det akustiska modelleringsprogram-met Olive Tree Lab. De tre fallen utgjordes av teoretiska platser, ett öppet gaturum,ett stängt gaturum samt ett gaturum med torg på ena sida. Utformningen av des-sa valdes utifrån att det är några av de vanligast förekommande urbana miljöernadär höga ljudnivåer uppstår. Utifrån litteraturstudien togs en beskrivningsmall förljudmiljöer som utgör den nya ljudanalysmetoden fram som sedan applicerades påfallstudien för analys och utvärdering. Mallens tyngdpunkt låg på att undersöka så-väl goda som negativa ljud och att koppla det till den platsen som analysen avser.Resultaten visade på att användning av mallen leder till en bredare och mer detalje-rad beskrivning av ljudmiljön som möjliggör flera olika typer av lösningar än de somföreslås idag. Noise is one of the environmental pollutions that has the largest negative effect onhuman health. Some of these effects are stress, sleeping issues and in some cases itcan cause cardiovascular diseases. The problem about this is growing as a result froman increasing population and an increasing urbanization. This study investigates thepossibilities to develop a new sound analysis method for urban environments. Today traffic noise investigations are performed as a part of environmental impact as-sessments. These analyses comprise most of sound level calculations from the primarynoise sources, which are then connected to the existing benchmarks for A-weightedsound levels at patios and facades. Research around urban sound environments showsthat only taking the sound levels exceeded from the primary noise sources in con-sideration is an insufficient method for estimating the sound quality. The relativeinvolvment of the noise, the range of frequencies and the variation in time as well,as the purpose and use of the area, are factors which are all connected to how wellthe noise is masked, as well as how disturbing the noise is actually percieved as. Allthese factors have to be taken into consideration in order to assess the sound qualityin the best posssible way. The method used in this study consisted of two main parts; one literature study,where available research around urban sound environments was analysed; and onecase study where three different cases of urban environments were analyzed in theacoustic modeling program Olive Tree Lab. The three cases consisted of theoreticallocations, one open street canyon, one closed and one street canyon with a squareon one side. Based on the literature study a description template for sound environ-ments was developed and applied to the cases from the case study for analysis andevaluation. The main focus of the template was to investigate both positive and ne-gative sounds and relate them to the site of which the sound analysis is intended for.The results showed that use of the template resulted in a broader and more detaileddescription of the sound environment, which enabled different kinds of solutions thatare not commonly used today.

The paper discusses that when architects design smart buildings, noise performance is quite often the last thing on their minds. But acoustic design is a critic factor in making sure your workspace is a place where you can actually work.

Noise in industrial workplaces has become an important occupational problem. Accordingly, there is a need to implement cost-effective strategies for reducing noise levels.In this paper, an optimal design methodology of passive acoustic treatments is proposed with the objective of minimizing the corresponding economic cost while keeping noise levels below tolerant limits. The methodology is based on a combination of a recently developed simplified acoustic diffusion model with a stochastic optimization technique known as "Simulated Annealing". The simplified diffusion model allows one to accurately evaluate multiple acoustic situations with a low computational cost, and the Simulated Annealing method is used to direct the search of the optimum set of design variables.Some numerical examples are presented in order to show the effectiveness of the proposed approach. Fil: Sequeira, Martin Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina Fil: Cortínez, Víctor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina

The quality of the patient's life while in the hospital setting is important and hence the quality of the hospital environment is equally important. The effect of noise on health varies depending upon the susceptibility of the individual, but can include higher blood pressure, stress and annoyance in staff, and can erode quality of care. This paper ascertains what the noise levels are in a typical renal unit and considers the potential effects on staff and patients. The quality of the hospital environment plays an important part in treating patients effectively and efficiently. The use of acoustic design principles can reduce the level and impact of noise and, in doing so, improve the quality of care and the patient experience.

The RV INVESTIGATOR is a quiet research vessel that has recently been built for CSIRO, the Australian Commonwealth Scientific and Industrial Research Organization. The vessel has stringent noise and vibration criteria, particularly with respect to underwater noise. Significant efforts were required in order for the vessel to be properly designed, constructed, and tested. This paper describes the efforts that were undertaken to achieve the noise goals and also presents the results of testing.

Paul Eade, General Manager of Acoustic Design Ltd., describes how railways offer him and his team of noise control and vibration engineers varied and interesting technical problems

Nowadays, sound is a critical part of our daily life and its unwanted and undesirable disturbances in the environment and in the workplace has induced much psychological and physical annoyance to human being and had also lessened the efficacy of the daily activities. Since the mechanical vibrations of molecules in the air had led in producing sound and considering profound damaging vibrations produced by the harsh sounds in the objects and instruments, we have studied the noise and the vibrations caused by it, together.With this introduction and Considering the potential devastating impact of noise and the need to keep staff which are working in the control room secure from this effects the power house of "Shahjid Madhaj" have proposed a project to control and limiting the noise in the control room by examining the diverse ways of transmitting sound into it. The project will be discussed here in details.

During operation, construction machines generate high noise levels which can adversely affect the health and the job performance of operators. The noise control techniques currently applied to reduce the noise transmitted into the operator cab are all based on the decrease of the sound pressure level. Merely reducing this noise parameter may be suitable for the compliance with the legislative requirements but, unfortunately, it is not sufficient to improve the subjective human response to noise. The absolute necessity to guarantee comfortable and safe conditions for workers, requires a change of perspective and the identification of different noise control criteria able to combine the reduction of noise levels with that of psychophysical descriptors representing those noise attributes related to the subjective acoustical discomfort. This paper presents the results of a study concerning the “customization” of a methodology based on Sound Quality for the noise control of construction machines. The purpose is to define new hearing-related criteria for the noise control able to guarantee not only reduced noise levels at the operator position but also a reduced annoyance perception.

The application of validated acoustic models to intake/exhaust system acoustic design is described with reference to a sequence of specific practical examples. These include large turbocharged diesel generating sets, truck engines, and high‐performance petrol engines.

Current industry standards related to controlling background sound in occupied spaces are all based on “not to exceed” maximum levels. At the other end of the scale, it is assumed that we cannot predict with any degree of certainty how low the background sound level may descend, what its spectral composition is, and when or how it may vary. Given that the “signal to noise ratio” is fundamental to all communication based acoustic design, the absence of this knowledge presents significant challenges. As a consequence, we adapt our acoustic designs to compensate for our inability to control minimum noise levels by over-specifying STC, CAC, and NRC values in order to obtain the desired results. And yet, precise generation of controlled minimum background sound levels is readily available. This session explores the negative impact of traditional compensatory acoustic design practises, the significant value of incorporating predictable/consistent minimum background sound levels into acoustic design planning, an...

Urban road traffic noise in cities is an ongoing and increasing problem across much of the world. Consequently a large amount of effort is expended in attempts to address this problem, especially in the area of acoustic design of buildings. Acoustic design policies developed by government authorities will typically focus on required transport noise reductions through a building façade to meet a specified internal noise levels. The significance of balcony acoustic treatments has been highlighted in recent decades yet this area has potentially been considered less important than the need for acoustic isolation of building facades. This paper outlines recent research that has been conducted in determining the significance of balcony acoustic treatments in mitigating urban road traffic noise. It summarizes recent literature, some of which focuses on technological advances in the knowledge of balcony acoustic design and some literature discusses the overall aims and benefits of balcony acoustic design. The aim of this paper is to promote the use of balcony acoustic design as a significant element in the overall solution towards mitigating road traffic noise in modern cities.

A multi-faceted study is conducted with the objective of estimating the potential fiscal savings in annoyance and sleep disturbance related health costs due to providing improved building acoustic design standards. This study uses balcony acoustic treatments in response to road traffic noise as an example. The study area is the State of Queensland in Australia, where regional road traffic noise mapping data is used in conjunction with standard dose–response curves to estimate the population exposure levels. The background and the importance of using the selected road traffic noise indicators are discussed. In order to achieve the objective, correlations between the mapping indicator (LA10 (18 hour)) and the dose response curve indicators (Lden and Lnight) are established via analysis on a large database of road traffic noise measurement data. The existing noise exposure of the study area is used to estimate the fiscal reductions in health related costs through the application of simple estimations of costs per person per year per degree of annoyance or sleep disturbance. The results demonstrate that balcony acoustic treatments may provide a significant benefit towards reducing the health related costs of road traffic noise in a community.

A recent operational need for the development of a large (101,000 ft3) reverberant acoustic chamber at the Space Power Facility of NASA Glenn Research Center’s Plum Brook Station with the requirement of generating sound pressure levels (SPL) as high as 163 dB has resulted in the need to re-examine the generation of noise in reverberant rooms. Early in the design stage, it was realized that the acoustic power level capability (10-30 kW) of conventional electrodynamic air modulators, such as those supplied by the Wyle Corporation, would be required in unprecedented numbers to meet the test spectra requirements. The design team then turned to a lesser known modulator, the hydraulically driven air modulator supplied by the Team Corporation, which has 150-200 kW acoustic power capability. The advantage to the project was a significant reduction in the number of modulators required to meet the requirements. However, since only limited characterization of Team modulator’s performance has been reported, a test program was required in order to mitigate the risk of the design of the RATF. Aiolos Corporation, which is responsible for the acoustic design of the RATF, and the Institute of Aerospace Research (IAR) of the National Research Council of Canada (NRC), entered into a collaborative agreement with the objective of characterizing, optimizing and investigating the controllability of the Team modulators. The test program was performed at the NRC-IAR reverberant chamber, a 19,000 ft3 facility located in Ottawa, Ontario, Canada. The current paper provides details of the principle of operation of the Team modulators, including their servo control loops and provides of a summary of the characterization and controllability test program., IMAC XXIX A Conference and Exposition on Structural Dynamics - Advanced Aerospace Applications, January 31 - Feb 3, 2011, Jacksonville, Florida, USA, Series: Conference Proceedings of the Society for Experimental Mechanics Series

The new EU's "Green Policy" and IMO regulation focused on reducing the environmental impact of vessels, origins new directives that shall affect the Shipbuilding Industry. The authors' participation in the SILENV and in the BESST projects within the FP7 has permitted to notice that the underwater radiated noise by the ships became the most outstanding novelty and the stronger challenge that needed to be technically solved. Following this new trend, the appearance of some class notations with "different limits" and the lack of consensus about the maximum noise levels that marine fauna can stand, makes difficult to define a clear technological strategy. Until an agreement is reached, the Shipbuilding industry will "fight against a ghost". In this "confusing scenario" this paper is a clear example of how the Shipbuilding industry is moving ahead to reduce the impact of the new ships. The dynamic and acoustic design carried out by the authors of the FRV "Ramon Margalef" for the Oceanographic Spanish Institute...

This paper presents a review of research carried out in the past 40 years into various aspects of noise in open plan classrooms. The emergence of open plan classroom design in response to progressive educational reforms is discussed. A limited amount of evidence of the effects of noise in open plan classrooms is presented. Surveys of both background and intrusive noise levels in open plan classrooms are summarized and compared. Differences between noise levels in open plan and enclosed classrooms are also considered. Recommended noise limits and acoustic design criteria for open plan classrooms are discussed, together with some current international standards. The paper concludes with a discussion of appropriate noise control measures to reduce noise and maximize speech intelligibility and speech privacy in open plan classrooms.

The world is urbanizing rapidly with more than half of the global population now living in cities. Improving urban environments for the well-being of the increasing number of urban citizens is becoming one of the most important challenges of the 21st century. Even though it is common that city planners have visions of a ’good urban milieu’, those visions are concerning visual aesthetics or practical matters. The qualitative perspective of sound, such as sonic diversity and acoustic ecology are neglected aspects in architectural design. Urban planners and politicians are therefore largely unaware of the importance of sounds for the intrinsic quality of a place. Whenever environmental acoustics is on the agenda, the topic is noise abatement or noise legislation – a quantitative attenuation of sounds. Some architects may involve acoustical aspects in their work but sound design or acoustic design has yet to develop to a distinct discipline and be incorporated in urban planning.My aim was to investigate to what extent the urban soundscape is likely to improve if modern architectural techniques merge with principles of acoustics. This is an important, yet unexplored, research area. My study explores and analyses the acoustical aspects in urban development and includes interviews with practitioners in the field of urban acoustics, situated in New York City. My conclusion is that to achieve a better understanding of the human living conditions in mega-cities, there is a need to include sonic components into the holistic sense of urban development.

Network Rail’s Thameslink Programme is designed to deliver a substantial increase in passenger capacity north-south across London. Part of the measures necessary to achieve this is the construction of new viaducts in central London south of the river Thames parallel to existing 19th century wrought iron viaducts. The route passes through a busy city area and it is vital for the project to demonstrate that it will minimise noise from the railway. Studies are reported here that assess bridge and track design to reduce noise - these use the ‘Norbert’ model for bridge noise rolling noise. A combined view of results for of old and new bridges has been used to show the important noise sources for ten sensitive receivers. The acoustic design for the area has then been optimised by looking at the effects of the combination of different track and bridge designs.

Acoustic testing of space systems and components is essential to the assurance of launch viability. Large acoustic test chambers that permit system-level testing are rapidly becoming the norm. The initial cost of such installations is typically 5 percent of that of a single large satellite. Their cost-effectiveness is easily demonstrated. This article provides design information on calculation of noise input power requirement; sound field uniformity; acoustic fatigue of chamber; noise breakout and soil vibration; and future trends in design.

Abatement of noise radiated by all kinds of vessels, and specially Underwater-Radiated Noise, because of its impacton marine life, has become the most outstanding novelty and the most dificult challenge the shipbuilding industryhas ever faced. Hence, the industry seeks to other new solutions to comply with the new guidelines and requirementsthat have been recently introduced and promoted by the EU, marine institutions, and the scientific community. "isnew topic, already studied and solved by the navies because of their strategic requirements, is now in the limelight andall the different aspects are being studied and discussed among the different players mentioned. In this new trend, theappearance of some class notations with “different limits”, assertions such as that the “propeller” is the major noise source,and the absence of consensus among the biological community about what should be the limits (for not affecting marine fauna), it is difficult to define the technological steps that should be followed. Until a consistent agreement is reached, the shipbuilding industry and the naval engineers will be “fighting against a ghost”. Within this “confusing scenario”, this paper is a clear example of how the Spanish shipbuilding industry is moving ahead to reduce the impact of new ships. The dynamic and acoustic design, developed by the authors, of the fishing research vessels “Ramón Margalef” and “Ángeles Alvariño” for the Oceanographic Spanish Institute and the experimental results obtained, in full compliance with ICES N°209 Underwater-Radiated Noise requirements, makes them reference vessels for the construction of “Silent Vessels”.

The quality of indoor environments such as commercial offices is affected by many factors, including temperature, humidity, air movement, illumination, ambient sound, and room acoustics. In 2012, a new laboratory was established at the University of Sydney to examine how such factors affect human occupants. In terms of sound, the design of the laboratory has three components: the acoustic design of the testing rooms; the audio system design (for introducing artificial soundscapes); and the design of generic soundscapes to support experimental work in the laboratory. Acoustic design considerations of the laboratory allow for the testing rooms to be configured as high grade office environments. The laboratory has a 24-channel audio system for introducing realistic and potentially complex sound fields in to the testing rooms, both from within and outside the rooms. Parametrically controlled soundscapes have been developed for interior sources (such as building services noise) and exterior sources (such as transport noise). This paper describes how the combination of the laboratory’s acoustics, audio systems, and soundscapes can be used for scientific studies of indoor environmental quality.

We live in a time of increasingly loud competing sounds and hearing loss is the number one disability in the world. Diverse populations of school children are especially vulnerable. The result is a degradation of the child’s academic achievement. New classrooms, built everyday, often incorporate acoustical barriers which limit students’ achievements. Overcoming these barriers involves funding constraints, construction timelines and lack of support which requires advocacy from parents, school boards, and design teams. This advocacy should include the ANSI Classroom Acoustics standards and an acoustical assessment of existing classrooms. Complex classroom acoustics challenges may include reduction of noise radiated by HVAC systems, improved acoustic treatment of external walls to minimize exterior noise and acoustic design of walls between adjacent noisy classrooms. Next steps for schools should be to retain an architect and/or an acoustical engineer for remodels and new school construction who are well versed in acoustics for educational settings and noise control. A booklet covering these issues, and designed as a practical guide for educators not versed in acoustics, is in preparation by the Acoustical Society of America.

There is a lack of acoustic performance standards for educational facilities in Egypt, especially university classrooms, resulting in a very bad acoustical quality. There is also a lack in the scientific research in that field of study in Egypt, although this type of research has been held in many other countries. This paper aims at studying the acoustic performance standards in different countries such as (ANSI-S12.60, 2010, BB93, 2003), and then using them to evaluate the acoustical quality in classrooms in Alexandria, including public and private, new and old constructions. The evaluation was done by three methods; B&K2250 SLM, Computer modeling using Odeon acoustic prediction software, and mathematical calculations using Sabine and Eyring formulae. The empirical study results were then compared to the recommended values by the previously mentioned standards. The study focused on sound levels, noise levels, reverberation time and Signal-to-Noise ratios. The results prove that there is a lack of acoustic design in Egypt. Most of the studied classrooms did not meet the recommended values. The main problem is using inappropriate finishing materials, which provide very high reverberation. Some simple and applicable proposals were suggested to improve the acoustical quality of classrooms. Predictions have shown a significant improvement.

Armstrong (China) Investment Co., Ltd., with support from Tongji University sponsored a school design competition, and this represents the winning student entry. This competition was intended to encourage students to express their knowledge of architectural acoustics and noise control in the design of a school in which acoustical considerations are of significant importance. Design included considerations of 1) the general architectural building design including both shape and location of the building relative to transportation noise sources, and 2) the specific architectural acoustic design of rooms, including noise control both within and between rooms. The design scenario was for a new primary school designed to replace an older school building at a site near Tongji University. The primary school will include grade levels from 1 to 6, with approximately 1000 pupils. This school building will include normal classrooms (number and size based on student population and design standards), cafeteria, auditorium, library, music rooms, gym, dancing room, etc, as are normally found in such a primary school. The school will consist of a single building, which may be a multi-level building.

Armstrong (China) Investment Co., Ltd., with support from Tsinghua University sponsored a school design competition, and this represents the winning student entry. This competition was intended to encourage students to express their knowledge of architectural acoustics and noise control in the design of a school in which acoustical considerations are of significant importance. Design included considerations of 1) the general architectural building design including both shape and location of the building relative to transportation noise sources, and 2) the specific architectural acoustic design of rooms, including noise control both within and between rooms. The design scenario was for a new primary school designed to replace an older school building at a site near Tsinghua University. The primary school will include grade levels from 1 to 6, with approximately 1000 pupils. This school building will include normal classrooms (number and size based on student population and design standards), cafeteria, auditorium, library, music rooms, gym, dancing room, etc, as are normally found in such a primary school. The school will consist of a single building, which may be a multi-level building.

There is an increasing body of research into the acoustic environment of hospitals, which provides evidence of the detrimental effects of noise on the well being and comfort of patients and on staff, and of a significant rise in hospital noise levels in recent years. Much of this evidence has focused on specific areas of healthcare such as critical care and operating theatres, with comparatively few studies carried out within general inpatient wards and in UK hospitals. A project is currently being undertaken to investigate, through objective and subjective surveys, the noise climate and acoustic design within general inpatient facilities in the United Kingdom, and their influence on the acoustic comfort of patients and staff. Noise and acoustic surveys have been carried out in a range of inpatient wards, with corresponding questionnaire surveys of staff and patients. Three major UK hospitals have been involved in the study, and a substantial amount of data has been collected. Reported results will include comparisons of noise levels measured in a number of ward locations including multibed and singlebed rooms, identification of the sources of high level noise, and some analysis of patient and staff attitudes to noise.

The R/V HUGH R. SHARP is a general purpose research vessel that is owned and operated by the University of Delaware. It has been designed to achieve the International Council for the Exploration of the Seas (ICES) underwater noise limit for Fisheries Research Vessels. This paper describes the design process, construction details, and final results with regard to the acoustic design of this ship. Both compartment airborne noise and underwater radiated noise predictions were carried using a proprietary shipboard noise prediction program. Noise control treatments that were used include: vibration isolated machinery, double‐stage isolated diesel generators, damping tiles, special acoustic insulation, and floating floors. After the vessel was completed a series of at‐sea tests was performed to check compliance to vibration, compartment noise, and underwater noise. Two problems were discovered with underwater noise levels. One was related to a gearbox and the other was related to the propellers. A discussion of...

More often than not, on noise research the dose‐response relationship shows a modest explained variance. A field study was carried out to investigate the effects of 13 different noise barriers, and 500 people exposed to noise were surveyed using questionnaires. First it seems that the acoustic effectiveness of the noise barriers is responsible for the reduction in annoyance. However, a detailed analysis shows that further factors moderate the relation between the noise parameters and the reaction to noise. It seems that simply introducing a noise barrier can cause a reduction in annoyance to an extent equivalent to 5 dB. This confirms the fact that the outdoor noise levels and the acoustic design of the surroundings are among the principle parameters influencing annoyance. In addition, annoyance is determined by individual acceptance of noise barriers. The degree of acceptance splits the reaction curve with a separation around 4 units on the rating‐scale of 11 units of annoyance. The design of the noise b...

Charts for acoustic design of a room in front of intrusive noise sources are the subject of this paper. The charts are based on modified room acoustics formulae, which yield consistent solutions, not to be obtained by the usual standards. The charts enable easy and quick determination of the necessary acoustic means for reduction of the level of the noise emanating into the room. Such a reduction may be well above 10 dB, even for periods of the day when windows are left open. The charts are useful for determining the size of windows and doors and the absorption area in the receiving room. They are useful also in the design of sound locks and sound transmission through various routes.

Acoustic design is an important consideration in mechanical services installations of all types and, with this in view, maximum noise levels in buildings are commonly specified by reference to either noise criterion (NC) or noise rating (NR) curves. Although these rating methods have existed for some years, confusion still arises from time to time regarding their use and appropriate measurement procedures. This Note is intended to assist engineers who are not primarily acousticians, but who are nevertheless charged with taking accurate and representative measurements to monitor and certify performance standards. The origin and applicability of rating indices are summarised and practical guidance given on field measurements.

The cost of a material is a property of it which is equally as important as the extent to which it attenuates or absorbs noise. Too little prominence is given to this fact, particularly in public. This paper considers and illustrates by examples the impact of costs on the choice of materials in acoustic design.

The usefulness of optical fibre hydrophones, and their practicality in phased arrays, is critically dependent upon the technology and systems philosophy adopted for their implementation. Previous work has demonstrated the principles of pulsed ref lectometric techniques in this context, and modifications to the basic system have improved its performance in three respects: that of the acoustic design of the sensor, that of the optical loss budget, and that of the ambient noise performance. In the range of 100Hz to lkHz, the system noise has been reduced to below ambient sea noise under most conditions. The system has been demonstrated with 2.2km of fibre lead between the sensor head and the optical system, with no discernible loss of performance.

Sound Pressure Level (SPL) in a manufacturing area is dependent on the radiation of noise from each machine tool, its sound power level (SWL) and energy absorption efficiency of the surrounding surface. The developed equation shows dependance of SPL on two additive factors. The first one is the total SWL in the area and the second includes the reverberation and radiation of noise effects.

The article presents an overview of noise control design problems on surface effect vehicles. There are several general operating characteristics and acoustic design features which make this type of craft different from conventional ships. As a result, attention must be given to all potential noise sources in order to achieve the objective of a quiet and habitable ship.

Castle Restaurant is situated in a quiet residential area of Kano City in Nigeria. A street separates it from the City Library now under construction. The management of the Restaurant has proposed to build a hall within the building which would be used for dancing, music, and a conference hall. This paper describes (a) the acoustic design of the hall which will meet the requirements of the multipurpose hall and (b) the steps taken to reduce the noise that would emanate from the hall so that neither the residents nor the users of the library would be disturbed.