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This manuscript describes a range of technical deliberations undertaken by the authors during their work as members of the Australian Government's Independent Scientific Committee on Wind Turbines. Central to these deliberations was the requirement upon the committee to improve understanding and monitoring of the potential impacts of sound from wind turbines (including low frequency and infrasound) on health and the environment. The paper examines existing wind turbine sound limits, possible perceptual and physiological effects of wind turbine noise, aspects of the effects of wind turbine sound on sleep health and quality of life, low-frequency noise limits, the concept of annoyance including alternative causes of it and the potential for it to be affected by low-frequency noise, the influence of amplitude modulation and tonality, sound measurement and analysis and management strategies. In so doing it provides an objective basis for harmonisation across Australia of provisions for siting and monitoring of wind turbines, which currently vary from state to state, contributing to contention and potential inequities between Australians, depending on their place of residence. [ABSTRACT FROM AUTHOR]

There are a number of standards and guidelines which are used in Australia for the assessment of wind farm noise, most of which provide different methods for measuring compliance once the wind farm is operational. This paper examines the differences that result when assessing compliance against the various compliance measurement and analysis procedures. Compliance measurements from a thirteen receivers at distances of 300 metres to 3 kilometres from six wind farm sites are used in the analysis. Differences of between 1.9 and 4.3 dB(A) are observed between the highest and lowest assessment results obtained at individual receivers, although this range is reduced to 1.9 - 2.7 dB(A) when LAeq results that appeared to be influenced by extraneous noise are discarded. These results complement the findings of our other paper which compares predicted levels against the compliance measurement results, and together these papers can be used to compare predictions against wind turbine noise levels measured and analysed using the different methodologies. [ABSTRACT FROM AUTHOR]

Copyright of Imaginations Journal is the property of Imaginations Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes the first demonstration of vibration isolation and suspension systems, which have been developed with view to application in the proposed Australian International Gravitational Observatory. In order to achieve optimal performance at low frequencies new components and techniques have been combined to create a compact advanced vibration isolator structure. The design includes two stages of horizontal preisolation and one stage of vertical preisolation with resonant frequencies ∼100 mHz. The nested structure facilitates a compact design and enables horizontal preisolation stages to be configured to create a superspring configuration, where active feedback can enable performance close to the limit set by seismic tilt coupling. The preisolation stages are combined with multistage three–dimensional (3D) pendulums. Two isolators suspending mirror test masses have been developed to form a 72 m optical cavity with finesse ∼700 in order to test their performance. The suitability of the isolators for use in suspended optical cavities is demonstrated through their ease of locking, long term stability, and low residual motion. An accompanying paper presents the local control system and shows how simple upgrades can substantially improve residual motion performance. [ABSTRACT FROM AUTHOR]

This paper reports on the examination of the relationship between self-reported historical noise exposure during leisure activities and audiological indicators: Measured hearing threshold levels (HTLs) and otoacoustic emissions (OAEs). The research was conducted by a cross-sectional survey of 1,432 individuals whose ages ranged from 11 years to 35 years. Methodology included a comprehensive audiometric assessment including otoscopy, pure tone audiometry (PTA) (air- and bone-conduction), OAEs, and tympanometry. A comprehensive questionnaire gathered information on demographics, hearing health status, and participation in work, non-work, and leisure activities. Using the history of work, non-work, and leisure noise exposure, a cumulative lifetime noise exposure was estimated. No correlation was found between cumulative lifetime noise exposure and audiometric PTA or OAE parameters.

In common with the rest of the developed world, road traffic noise has been a public policy issue in Australia for many years. From attitudinal studies relating to noise in the environment, it is consistently shown that the higher annoyance scores for noise heard within the home result from road traffic noise. Governments in Australia, at all levels, have responded with a range of traffic noise management measures. At the federal government level these have primarily related to reducing noise at the source, namely the vehicle. State governments have developed traffic noise policies to guide the design for major roads and to control the planning of new noise-sensitive areas adjacent to major road corridors. Local governments have also considered traffic noise and introduced local traffic management measures on roads they control. This paper reviews and discusses the approaches in the different policies in current use in Australian states and territories for the management of road traffic noise. [ABSTRACT FROM AUTHOR]

Global population growth and associated urban development are having profound effects on biodiversity. Two major outcomes of expanding development that affect wildlife are light and noise pollution. In this paper, we review literature reporting the effects of light and noise on biodiversity, and assess implications for conservation planning in Australia. Our results clearly indicate that light and noise pollution have the potential to affect the physiology, behaviour and reproduction of a range of animal taxa. Types of effects include changes in foraging and reproductive behaviours, reduction in animal fitness, increased risk of predation and reduced reproductive success. These could have flow-on consequences at the population and ecosystem levels. We found a significant gap in knowledge of the impact of these pollutants on Australian fauna. To reduce the effect of light and noise pollution, there needs to be careful planning of urban areas in relation to protected areas, and for biodiversity more generally. Potential measures include strategically planning the types of development and associated human activities adjacent to protected areas, and the use of shields and barriers, such as covers for lights or the use of dense native vegetation screens, while still allowing movement of animals. Changes in government standards and regulations could also help to reduce the impacts of light and noise pollution. [ABSTRACT FROM AUTHOR]

The behavioural response study (BRS) is an experimental design used by field biologists to determine the function and/or behavioural effects of conspecific, heterospecific or anthropogenic stimuli. When carrying out these studies in marine mammals it is difficult to make basic observations and achieve sufficient samples sizes because of the high cost and logistical difficulties. Rarely are other factors such as social context or the physical environment considered in the analysis because of these difficulties. This paper presents results of a BRS carried out in humpback whales to test the response of groups to one recording of conspecific social sounds and an artificially generated tone stimulus. Experiments were carried out in September/October 2004 and 2008 during the humpback whale southward migration along the east coast of Australia. In total, 13 'tone' experiments, 15 'social sound' experiments (using one recording of social sounds) and three silent controls were carried out over two field seasons. The results (using a mixed model statistical analysis) suggested that humpback whales responded differently to the two stimuli, measured by changes in course travelled and dive behaviour. Although the response to 'tones' was consistent, in that groups moved offshore and surfaced more often (suggesting an aversion to the stimulus), the response to 'social sounds' was highly variable and dependent upon the composition of the social group. The change in course and dive behaviour in response to 'tones' was found to be related to proximity to the source, the received signal level and signal-to-noise ratio (SNR). This study demonstrates that the behavioural responses of marine mammals to acoustic stimuli are complex. In order to tease out such mulUfaceted interactions, the number of replicates and factors measured must be sufficient for multivariate analysis. [ABSTRACT FROM AUTHOR]

This paper presents and discusses the results of basic source finding tests in three dimensions (using spectroscopic data cubes) with duchamp, the standard source finder for the Australian Square Kilometre Array Pathfinder. For this purpose, we generated different sets of unresolved and extended Hi model sources. These models were then fed into duchamp, using a range of different parameters and methods provided by the software. The main aim of the tests was to study the performance of duchamp on sources with different parameters and morphologies and assess the accuracy of duchamp's source parametrisation. Overall, we find duchamp to be a powerful source finder capable of reliably detecting sources down to low signal-to-noise ratios and accurately measuring their position and velocity. In the presence of noise in the data, duchamp's measurements of basic source parameters, such as spectral line width and integrated flux, are affected by systematic errors. These errors are a consequence of the effect of noise on the specific algorithms used by duchamp for measuring source parameters in combination with the fact that the software only takes into account pixels above a given flux threshold and hence misses part of the flux. In scientific applications of duchamp these systematic errors would have to be corrected for. Alternatively, duchamp could be used as a source finder only, and source parametrisation could be done in a second step using more sophisticated parametrisation algorithms. This paper discusses the results of basic source finding tests with the duchamp source finder on different source models. We find duchamp to be a powerful source finder, capable of reliably detecting sources down to low signal-to-noise ratios. duchamp's measurements of basic source parameters, however, are affected by systematic errors. [ABSTRACT FROM AUTHOR]

During construction of a new freeway in Melbourne, it was found that tonal wind-induced noise was being generated by the finned balustrades of architecturally-designed pedestrian overpasses which had been installed at several locations along the route. As the level of wind-induced noise was unacceptable at residences in the vicinity of the overpasses, a solution to reduce or eliminate the noise had to be developed. The solution needed to be practical to retrofit to the existing structure, while satisfying strict project constraints in relation to urban design, design life, and safety in design rules. This paper outlines the investigation that was undertaken to determine the wind-conditions under which the noise occurred, discusses the noise-generation mechanisms that were established to be causing the noise, and presents a summary of the potential solutions that were identified through theoretical analysis, wind tunnel modelling and field trials. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Applied Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study compared the pre-employment median hearing threshold level (HTL) distribution from a population of coal miners from New South Wales (NSW), Australia, to an otologically normal, age-matched population described by the International Standards Organisation (ISO) ISO 7029:2019, to determine any differences. This was an observational, retrospective, repeated cross-sectional study. De-identified audiometric records of 59,601 male employees entering NSW coal mining in three representative five-year periods between 1991 and 2015 were utilised. The median HTL deviation of the mining population was statistically significantly different (p < 0.05) from the ISO population, for almost all analyses. Overall, the mining population cohorts have higher (worse) median HTLs compared to the ISO population. The greatest difference occurs at 4 kHz in older age groups, likely indicating noise-induced hearing loss. These findings indicate that some NSW coal mine workers commence their careers with evidence of pre-existing hearing loss (HL), in an industry with excessive noise exposures. These results provide Australian mining and other noisy industries with evidence to support a review of hearing conservation strategies to improve mitigation of hearing loss across the working lifespan. The coal mining industry in Australia typically employs 20,000–30,000 workers annually. These workers are potentially exposed to noise levels between 80 dB(A) and 120 dB(A) whilst at work, and thus at high risk of developing noise induced hearing loss (NIHL). NIHL is the most compensated, occupational disease for coal mining in Australia, costing the Australian State of New South Wales (NSW) up to $4 million each year. And yet: NIHL is entirely preventable. This is the second of two studies of Australian coal mining, analysing a database containing de-identified mandatory audiometric testing results. Evidence of hearing loss within this population was determined in the first study, and the aim of this follow-up study was to determine if there were differences in the median hearing threshold levels in the mining population compared to an otologically normal, international population (ISO7029). The results indicate that the mining population HTLs for males are significantly different (worse) compared to an age and gender matched otologically normal population, specifically at 4 kHz for older workers. Evidence of age-related hearing loss was also found. From a workplace perspective, employers need to consider appropriate workplace interventions to promote hearing loss prevention strategies across the workforce. This information can be used to inform future noise and hearing policies and procedures within this, as well as other noisy industries, to prevent and reduce further exposure of workers to excessive noise. [ABSTRACT FROM AUTHOR]

BACKGROUND: Large electricity-generating wind turbines emit both audible sound and inaudible infrasound at very low frequencies that are outside of the normal human range of hearing. Sufferers of wind turbine syndrome (WTS) have attributed their ill-health and particularly their sleep disturbance to the signature pattern of infrasound. Critics have argued that these symptoms are psychological in origin and are attributable to nocebo effects. OBJECTIVES: We aimed to test the effects of 72 h of infrasound (1.6–20 Hz at a sound level of ~90 dB pk re 20 μPa, simulating a wind turbine infrasound signature) exposure on human physiology, particularly sleep. METHODS: We conducted a randomized double-blind triple-arm crossover laboratory-based study of 72 h exposure with a >10-d washout conducted in a noise-insulated sleep laboratory in the style of a studio apartment. The exposures were infrasound (~90 dB pk), sham infrasound (same speakers not generating infrasound), and traffic noise exposure [active control; at a sound pressure level of 40–50 dB LAeq,night and 70 dB LAFmax transient maxima, night (2200 to 0700 hours)]. The following physiological and psychological measures and systems were tested for their sensitivity to infrasound: wake after sleep onset (WASO; primary outcome) and other measures of sleep physiology, wake electroencephalography, WTS symptoms, cardiovascular physiology, and neurobehavioral performance. RESULTS: We randomized 37 noise-sensitive but otherwise healthy adults (18–72 years of age; 51% female) into the study before a COVID19-related public health order forced the study to close. WASO was not affected by infrasound compared with sham infrasound (-1.36 min; 95% CI: -6.60, 3.88, 푝 = 0.60) but was worsened by the active control traffic exposure compared with sham by 6.07 min (95% CI: 0.75, 11.39, 푝 = 0.02). Infrasound did not worsen any subjective or objective measures used. DISCUSSION: Our findings did not support the idea that infrasound causes WTS. High level, but inaudible, infrasound did not appear to perturb any physiological or psychological measure tested in these study participants. [ABSTRACT FROM AUTHOR]

Summary: Background: The practice environment of the emergency department (ED) refers to both the people and physical factors (architecture) in the environment in which health care is provided. ED triage practice environments are the very places where caring or the delivery of health care often begins. This paper examines the implications of the emergency department triage practice environment on the triage practice of nurses who triage clients with a mental illness. Methods: An observational ethnographic approach inclusive of participant observation, formal and informal semi structured interviews, examination of documents and the collation of field notes were the means of data collection. Data was analysed through constant comparison and theoretical coding. Results: Nurses who work in ED triage are cognisant of environmental impacts as they undertake rapid client assessment and manage busy and noisy waiting rooms. The triage environment does influence the ED triage assessment and the management of clients who present seeking mental health care. Conclusions: Tensions arise when the architectural environment of an ED triage area affects client behaviour, the capacity to provide optimal client care and the ability to conduct a triage assessment that obtains the best data possible. Understanding the impact of the ED triage practice environment on people with a mental illness facilitates an understanding of how people from this client group can be better supported in a complex and busy ED environment. [Copyright &y& Elsevier]

The spectral line datacubes obtained from the Square Kilometre Array (SKA) and its precursors, such as the Australian SKA Pathfinder (ASKAP), will be sufficiently large to necessitate automated detection and parametrisation of sources. Matched filtering is widely acknowledged as the best possible method for the automated detection of sources. This paper presents the Characterised Noise Hi (cnhi) source finder, which employs a novel implementation of matched filtering. This implementation is optimised for the 3-D nature of the Hi spectral line observations of the planned Wide-field ASKAP Legacy L-band All-sky Blind surveY (WALLABY). The cnhi source finder also employs a novel sparse representation of 3-D objects, with a high compression rate, to implement the Lutz one-pass algorithm on datacubes that are too large to process in a single pass. WALLABY will use ASKAP's phenomenal 30 square degree field of view to image ~70% of the sky. It is expected that WALLABY will find 500 000 Hi galaxies out to z ~ 0.2. The Characterised Noise Hi source finder uses a novel approach to find sources in Hi spectral line datacubes using matched filtering. The concept, initial implementation and testing are presented here. [ABSTRACT FROM AUTHOR]

The recently published NSW Planning Guidelines - Wind Farms (the draft Guideline) presents a planning and assessment framework for a range of issues including recommendations for the assessment of noise impacts. These recommendations build upon existing assessment methods used throughout Australia, and helpfully include prescriptive guidance for a number of issues that are not well defined in existing guidance documents. Conversely, the draft Guideline introduces significant new requirements which may add a high level of complexity to the planning process. This technical note presents a discussion of some of the important features of the noise assessment recommendations proposed in the draft Guideline, including proposed noise criteria, measurement techniques, prediction methods and assessment of specific noise characteristics. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to explore health professionals' perceptions of the impact of noise on communication in the operating room. Sample and setting Health professionals working in the operating room at a tertiary, affiliated, major referral hospital in northern Australia were recruited using purposive sampling. Method Semi-structured interviews were undertaken using an exploratory qualitative design to explore health professionals' perceptions of communication and the impact of noise in the operating room. Interviews were transcribed verbatim and analysed using thematic analysis. Results In all, 26 health professionals participated, including anaesthetists, surgeons, nurses and theatre technicians. Two themes were analysed from the data: barriers to communication and facilitators of communication in the operating room. Barriers to communication focused on difficulties that health professionals experienced when attempting to communicate in the presence of noise -- difficulty hearing in noisy operating rooms, positioning of health professionals, and inability to filter out sounds. Facilitators of communication consisted of health professionals' adaption to the presence of noise during communication -- non-verbal communication, such as gestures, and the ability to filter out unwanted sounds. Conclusion Health professionals of all levels of experience encounter communication difficulties. With increased experience, health professionals are able to filter out unwanted sounds provided the OR is not too noisy. Consideration needs to be given to the use of space and positioning of noise emitting equipment to optimise communication in the OR. Furthermore, communication can be facilitated by the judicious use of non-verbal communication. [ABSTRACT FROM AUTHOR]

In coastal water systems, horizontal chaotic dispersion plays a significant role in the distribution and fate of pollutants. Lagrangian Coherent Structures (LCSs) provide useful tools to study the problem of the transport of pollutants and have only recently been applied to coastal waters. While the fundamentals of the LCS approach using idealised analytical flow fields are well established in the literature, there are limited studies on their practical implementations in coastal waters where effects of boundaries and bathymetry frequently become significant. Due to their complex bathymetry and boundaries, unstructured grid systems are commonly used in modelling of coastal waters. For convenient derivation of LCS diagnostics, structured grids are commonly used. Here we examine the effect of mesh resolution, interpolation schemes and additive random noise on the LCS diagnostics in relation to coastal waters. Two kinematic model flows, the double gyre and the meandering jet, as well as validated outputs of a hydrodynamic model of Moreton Bay, Australia, on unstructured grids are used. The results show that LCSs are quite robust to the errors from interpolation schemes used in the data conversion from unstructured to structured grid. Attributed to the divergence in the underlying flow field, the results show that random errors in the order of 1–10% cause a breakdown in the continuity of ridges of maximum finite-time Lyapunov exponents and closed orbit elliptic LCSs. The result has significant implications on the suitability of applying LCS formulations based on a deterministic flow field to diffusive coastal waters. Highlights: The work examines the sensitivities of applying Lagrangian coherent structure (LCS) diagnostics for coastal waters with complex boundaries. LCSs are robust to the errors from interpolation schemes used for unstructured to structured grid velocity data conversion. Additive random errors in the order of 1–10 % cause a breakdown in the continuity of ridges of maximum finite-time Lyapunov exponents and closed orbit elliptic LCSs. [ABSTRACT FROM AUTHOR]

Abstract The aim of this manuscript is to summarize the current scenarios encompassing noise exposure in the workplace and the risk of noise-induced hearing loss (NIHL) in Asia. NIHL is the most prevalent and preventable occupational disease in most Asian countries. Sources of noise in these countries include manufacturing and agriculture industries, exploitation of natural resources, and urban traffic. The highest attributable fraction of adult-onset hearing loss resulting from noise exposure in the world comes from Asian countries. NIHL is a serious health problem in Asia, not only because of the number of affected labourers, but also because the majority of Asian countries are still developing economies where access to health services and preventive programmes are limited. Lack of awareness about NIHL among employers, employees, and health care professionals is one of the main barriers for the prevention of NIHL in Asia. In this paper, the sources of noise, NIHL prevalence in different industries, local legislation, and research publications on NIHL from Asia are discussed. Sumario El propóósito de este manuscrito es resumir los escenarios actuales relacionados con la exposicióón a ruido en el lugar de trabajo y el riesgo de hipoacusia inducida por ruido (NIHL) en Asia. La NIHL es la enfermedad ocupacional máás prevalente y prevenible en la mayoríía de los paííses asiááticos. Las fuentes de ruido en estos paííses incluyen las industrias de manufactura y agricultura, la explotacióón de los recursos naturales y el trááfico urbano. La fraccióón máás alta en el mundo atribuible de la hipoacusia de inicio en la edad adulta proveniente de la exposicióón a ruido, viene de los paííses asiááticos. La NIHL es un serio problema de salud en Asia, no sóólo por el núúmero de trabajadores afectados, sino porque la mayoríía de los paííses asiááticos aúún son economíías en desarrollo, donde el acceso a los servicios de salud y a los programas preventivos es limitado. La falta de conciencia sobre la NIHL entre los empleadores, los empleados y los profesionales en salud, es una de las principales barreras para la prevencióón de la NIHL en Asia. En este trabajo, se discuten las fuentes de ruido, la prevalencia de NIHL en las diferentes industrias, la legislacióón local y las publicaciones de investigacióón sobre NIHL. [ABSTRACT FROM AUTHOR]

Abstract This paper reports real world preferences of children in a double-blind, cross-over trial comparing NAL-NL1 and DSL v.4.1 prescriptions. Twenty-four children wore digital WDRC hearing aids at each site (Australia, Canada). Multi-memory hearing aids provided the NAL and DSL programs in each of two memories. Diaries were completed during two counterbalanced trials, providing overall preference, situational preference, and preference comments. Ratings were reliable, and situational preferences factored into quiet/low level situations versus noisy/reverberant/high level situations. Children at both sites used DSL v4.1 for hearing low level speech, or when they wanted to hear loudly and clearly. Children used NAL-NL1 when they wished to hear sounds at a lower level, or to reduce background noise. Children expressed strong preferences for having the choice of both programs. Canadian children were more likely to prefer DSL than were the Australian children. Factors such as listening environment and prior listening experience are discussed in interpreting these findings. Sumario Este trabajo reporta las preferencias de los niños en el mundo real, en un estudio cruzado, doble-ciego que compara las prescripciones NAL-NL1 y DSL v4.1. Veinticuatro niños de dos sitios (Australia, Canada) utilizaron auxiliares auditivos digitales con WDRC. Los auxiliares auditivos con multi-memoria contaban con los programas NAL y DSL en dos de sus memorias. Se completaron diarios durante dos ensayos balanceados que proporcionaban información sobre la prefer-encia general, la preferencia situacional y comentarios sobre la preferencia. Las puntuaciones fueron confiables y la preferencia situacional se clasificaron en situación silente/nivel bajo versus situación ruidosa/reverberante/nivel alto. Los niños de ambos lugares utilizaron DSL v4.1 para escuchar el habla a intensidad baja o cuando querían escuchar alto y claro. Los niños expresaron una fuerte preferencia por poder tener la opción de ambos programas. Los niños canadienses tendieron a preferir DSL más que los niños australianos. Factores como el ambiente sonoro y las experiencias auditivas previas se discuten y se interpretan los hallazgos. [ABSTRACT FROM AUTHOR]

Objective: The ability to determine the location of the sound source is often important for effective communication. However, it is not clear how the localisation is affected by background noise. In the current study, localisation in quiet versus noise was evaluated in adults both behaviourally, and using MMN and P3b. Design: The speech token/da/was presented in a multi-deviant oddball paradigm in quiet and in presence of speech babble at +5 dB SNR. The deviants were presented at locations that differed from the standard by 30°, 60° and 90°. Study sample: Sixteen normal hearing adults between the age range of 18–35 years participated in the study. Results: The results showed that participants were significantly faster and more accurate at identifying deviants presented at 60° and 90° as compared to 30°. Neither reaction times nor electrophysiological measures (MMN/P3b) were affected by the background noise. The deviance magnitude (30°, 60° and 90°) did not affect the MMN amplitude, but the smaller deviant (30°) generated P3b with smaller amplitude. Conclusions: Under the stimulus paradigm and measures employed in this study, localisation ability as effectively sampled appeared resistant to speech babble interference. [ABSTRACT FROM AUTHOR]

Passive acoustic recordings made in Fowlers Bay, South Australia, during the austral winter of 2013–2017 revealed the presence of several sources of underwater sound. Sound sources of biological origin include baleen and toothed whales, fish and shrimp. Physical sources of underwater sound include wind- and rain-driven noises, and underwater sounds of anthropogenic origin were primarily from boats and occasionally from an aircraft. Biological sound sources were commonly recorded within the frequency range of around 25 Hz to nearly 17 kHz, with baleen whales within the range of ~ 25 Hz to 6 kHz, and dolphins at higher frequencies of approximately 2.5–17 kHz. Broadband sounds from physical and anthropogenic sound sources were noticeable at frequencies above ~ 50 Hz. The ambient noise level in Fowlers Bay at frequencies below 100 Hz was relatively low (around 75 dB re 1 µPa2/Hz for the 95% percentile) due to an insignificant contribution of noise from distant shipping. At higher frequencies, the noise level was governed primarily by noise from wind and varied by nearly 30 dB re 1 µPa2/Hz depending on weather conditions, up to around 80 dB re 1 µPa2/Hz for the 95% percentile during periods of strong winds and intense rainfall. [ABSTRACT FROM AUTHOR]

Sound of Decay consists of a deceased cane toad (Rhinella marinus) in a glass desiccator which serves as a stage for the audio playback of the toad's material decomposition. Cane toads were imported to Australia to control agricultural pests--a role they soon ignored, spreading widely. As a form of highly active "vibrant matter" (Bennett), the activity of the toad extends beyond mortality--disproving Cage's proposition that the absence of sound is equivalent to death. Sound of Decay prompts listeners to partake in an inter-species exchange which "lacks finality" (Nyquist), whereby cane toads emerge as something akin to bio-cultural noise. [ABSTRACT FROM AUTHOR]

Objective: This study investigated clinical care delivered to musicians in Australia by audiologists and manufacturers of musicians’ hearing protectors (MHP).Design: Audiologists with experience treating musicians were invited to complete a survey on their service delivery. A second survey was administered to manufacturers of MHPs.Study sample: Four manufacturers of MHP and 31 audiologists completed the surveys. Post hoc analyses were performed comparing the responses of audiologists with more versus less clinical experience; and those with and without musical training.Results: There was considerable variation in the audiological care provided to musicians. Only one-third of audiologists performed pure-tone audiometry prior to MHP fitting, and there was little consistency across the sample in relation to impression taking, preferred attenuation or selection of canal length. There was also significant variation in the manufacturers’ approach to MHP, each of whom provided different recommendations regarding preferred impression techniques and material viscosity.Conclusions: The results of this study reveal lack of consistency across the hearing healthcare sector with respect to care of musicians’ hearing, with potential to impact upon the satisfaction with, and usage of, MHP. There is need for evidence-based, best practice guidelines and training to support clinical audiologists in providing optimal care. [ABSTRACT FROM AUTHOR]

The number of people receiving maintenance haemodialysis (HD) in Australia has increased from 251 per million population in 1995 to 515 per million population in 2014. In-centre night haemodialysis (INHD) was introduced in one unit as a response to the rising numbers of people requiring HD. This study was designed as a quality project to evaluate a new service and its impact on the patients during the first 12 months of the INHD service. Patients were interviewed at initiation of INHD and then at six and 12 months. Thematic analysis was used to provide a descriptive account of receiving HD therapy in an in-centre environment at night. Findings of the study showed that INHD has positive effects on physical health and lifestyle, but that patients also experienced new symptoms related to longer hours of dialysis and poor sleep quality. Patients felt isolated from the rest of the dialysis patients and adapted the INHD environment to suit their own personal needs. INHD is a new approach to the delivery of HD treatments, which has been developed in response to the increasing demand for dialysis services. More study is required into this novel model of care to understand the risks and benefits of INHD to patients and staff, and to optimise the delivery of safe and effective HD. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study is to characterise ambient sound levels of paediatric and neonatal intensive care units in an old and new hospital according to current standards.Methods: The sound environment was surveyed for 24-h data collection periods (n = 80) in the Neonatal and Paediatric Intensive Care Units (NICUs and PICUs) and Special Care Nursery of the old and new Royal Children's Hospital Melbourne. The ambient sound environment was characterised as the proportion of time the ongoing ambient sound met standard benchmarks, the mean 5-s sound levels and the number and duration of noise events.Results: In the old hospital, none of the data collection periods in the NICU and PICU met the standard benchmark for ongoing ambient sound, while only 5 of the 22 data collection periods in the new hospital met the recommended level. There was no change in proportion of time at recommended Leq between the old and the new Special Care Nursery. There was strong evidence for a difference in the mean number of events >65 dBA (Lmax ) in the old and new hospital (rate ratio = 0.82, 95% confidence interval: 0.73 to 0.92, P = 0.001). The NICU and PICU were above 50 dBA in 75% of all data collection periods, with ventilatory equipment associated with higher ongoing ambient sound levels.Conclusions: The ongoing ambient sound suggests that the background sound environment of the new hospital is not different to the old hospital. However, there may be a reduction in the number of noise events. [ABSTRACT FROM AUTHOR]

Purpose: Open-plan classroom styles are increasingly being adopted in Australia despite evidence that their high intrusive noise levels adversely affect learning. The aim of this study was to develop a new Australian speech perception task (the Mealings, Demuth, Dillon, and Buchholz Classroom Speech Perception Test) and use it in an open-plan classroom to assess how intrusive noise affects speech perception. Method: The first part of this article describes how the online 4-picture choice speech perception task materials were created. The second part focuses on the study involving twenty-two 5- to 6-year-old children in an open-plan classroom who completed the task while other classes engaged in quiet and noisy activities. Results: Children's performance accuracy, number of responses, and speed were lower in the noisy condition compared with the quiet condition. In addition, children's speech perception scores decreased the farther away they were seated from the loudspeaker. Overall, the children understood and were engaged in the task, demonstrating that it is an appropriate tool for assessing speech perception live in the classroom with 5- to 6-year-old children. Conclusions: The results suggest that the Mealings, Demuth, Dillon, and Buchholz Classroom Speech Perception Test is a helpful tool for assessing speech perception in classrooms and that it would be beneficial to use in future research investigating how classroom design and noise affect speech perception. [ABSTRACT FROM AUTHOR]

Objective: Detailed information on the hearing threshold levels (HTLs) of young Australians was gathered as part of a large-scale study of the relationship between HTL and leisure-noise exposure in young Australians. Design: HTL data for the study population (18 -35 year olds) was carefully collected, as well as otoscopy, tympanometry, contra-lateral acoustic reflexes, and otoacoustic emissions (transient and distortion product), together with a comprehensive hearing health history - both past and present. Study sample: The sample cohort consisted of 1407 individuals, females and males. Results: Prior to analysis, HTL data were filtered according to both a 'Low' and 'High' set of exclusion criteria. The results obtained for both high-screen and low-screen datasets were around +5 dB above the traditionally accepted values of audiometric zero. This is consistent with previous published reports. Conclusion: Comparison with 'ISO 7029 Acoustics: Statistical distribution of hearing thresholds as a function of age' indicated that threshold values for this dataset have a similar distribution to those of the Standard. This data provides a suitable reference HTL ('normative') database for young Australians. [ABSTRACT FROM AUTHOR]

A 9-yr dataset of continuous sea noise recording made at the Cape Leeuwin station of the Comprehensive Nuclear-Test-Ban Treaty hydroacoustic network in 2002-2010 was processed to detect calls from pygmy blue whales and to analyze diurnal, seasonal, and interannual variations in their vocal activity. Because the conventional spectrogram correlation method for recognizing whale calls in sea noise resulted in a too high false detection rate, alternative algorithms were tested and the most robust one applied to the multi-year dataset. The detection method was based on multivariate classification using two spectrogram features of transients in sea noise and Fisher's linear discriminant, which provided a misclassification rate of approximately 1% for missed and false detections at moderate sensitivity settings. An analysis of the detection results revealed a consistent seasonal pattern in the whale presence and considerable interannual changes with a steady increase in the number of calls detected in 2002-2006. An apparent diurnal pattern of whales' vocal activity was also observed. The acoustic detection range for pygmy blue whales was estimated to vary from about 50 km to nearly 200 km from the Cape Leeuwin station, depending on the ambient noise level, source level, and azimuth to a vocalizing whale. [ABSTRACT FROM AUTHOR]

Abstract Objective: To investigate young people's experiences and attitudes towards hearing health and their participation in noise reduction behaviours, to better understand how education and prevention messages may be better targeted. Design: An online survey was used to investigate participants' own hearing health, their engagement with noise reduction behaviour, and their beliefs about hearing health and the risk posed by leisure activities. Study sample: Results are presented for 1000 Australian young adults (18-35 years). Results: Most participants reported current good hearing health, although over a fifth showed possible early warning signs of damage. Approximately half of participants took steps to reduce their noise exposure. However, preventative action was not related to hearing loss symptomology, or perceived personal risk of noise-related damage. Participants' engagement with hearing health was related to beliefs about the risk posed by leisure noise, hearing health awareness, and the importance of hearing. Conclusions: There is a need to further educate young people about the risks posed to hearing by leisure activity participation and factors that may assist improve hearing health. It is important that hearing health messages move past the traditional emphasis on knowledge, and move towards the use of more personalized motivators of noise reduction behaviour. [ABSTRACT FROM AUTHOR]

We develop a new linearly-constrained recursive total least squares adaptive filtering algorithm by incorporating the linear constraints into the underlying total least squares problem using an approach similar to the method of weighting and searching for the solution (filter weights) along the input vector. The proposed algorithm outperforms the previously proposed constrained recursive least square (CRLS) algorithm when both input and output data are observed with noise. It also has a significantly smaller computational complexity than CRLS. Simulations demonstrate the efficacy of the proposed algorithm. [ABSTRACT FROM PUBLISHER]

Infrasound is generated by a range of natural and engineered sources. The measurement of infrasound at low levels requires a specific methodology, as it is readily affected by even light surface breezes on the microphone. Such a methodology, based on measurements below the ground surface in a test chamber, has been developed to measure infrasound at two Australian wind farms and also in the vicinity of a beach, a coastal cliff, the city of Adelaide and a power station. The measured levels have been compared between each source and against the infrasound audibility threshold of 85 dB(G). The measured level of infrasound within the wind farms is well below the audibility threshold and is similar to that of urban and coastal environments and near other engineered noise sources. [ABSTRACT FROM AUTHOR]

Human perception responds primarily to sound character rather than sound level. Wind farms are unique sound sources and exhibit special audible and inaudible characteristics that can be described as modulating sound or as a tonal complex. Wind farm compliance measures based on a specified noise number alone will fail to address problems with noise nuisance. The character of wind farm sound, noise emissions from wind farms, noise prediction at residences, and systemic failures in assessment processes are examined. Human perception of wind farm sound is compared with noise assessment measures and complaint histories. The adverse effects on health of persons susceptible to noise from wind farms are examined and a hypothesis, the concept of heightened noise zones (pressure variations), as a marker for cause and effect is advanced. A sound level of LAeq 32 dB outside a residence and above an individual’s threshold of hearing inside the home are identified as markers for serious adverse health effects affecting susceptible individuals. The article is referenced to the author’s research, measurements, and observations at different wind farms in New Zealand and Victoria, Australia. [ABSTRACT FROM PUBLISHER]

This study compares the hearing status and behaviors of Australian farmers from 1994-2001 with those from 2002-2008. Over this period the authors found (1) there was a 12.5% overall improvement in the proportion of farmers with normal hearing in left ears, with the likelihood of a screening participant having normal hearing improving by almost 9% each year; (2) significant improvements in the mean hearing threshold of both ears from 1 to 6 kHz; (3) significantly higher mean hearing thresholds for 35- to 44-year-old farmers exposed to firearms, chainsaws, workshop tools, heavy machinery, and tractors with cabins compared to nonexposed groups; (4) nonuse of hearing protection devices by young farmers (15 to 24 years old), was associated with hearing loss for those using uncabined tractors. Despite a reduction in noise injury, further adoption of noise reduction strategies for specific agricultural work practices is required. [ABSTRACT FROM AUTHOR]

A theoretical model for predicting noise reduction in coupled workshops is presented by using statistical energy analysis (SEA) method. An opening between the coupled workshops is considered into the theoretical model properly. The leakage issue is dealt with in the process of SEA modeling. An experiment is also carried out. A reasonable agreement between the prediction of noise reduction and the experimental data is observed. Moreover, it is concluded from the simulations that the sound energy transmit through the opening was the most important way to affect the noise reduction and the leakage is a significant element to influence the effect of noise treatment. [ABSTRACT FROM AUTHOR]