Industrial Noise Exposure Research Articles

Investigation of Noise Induced Hearing Loss Among Power Loom Industry Workers in Tamil Nadu, India.

Noise-induced hearing loss remains a prevalent occupational concern across various industries. This study aimed to address several key objectives regarding noise exposure and hearing impairment among power loom workers in Tamil Nadu, India. The major objectives were to assess the levels of noise exposure in the power loom industry and to determine the prevalence of hearing loss among the workers. The minor objectives included identifying the specific factors associated with hearing loss and proposing measures to mitigate noise exposure. A cross-sectional study was carried out at a Power Loom Industry in the Erode District of Tamil Nadu between September and November 2023. A total of 123 workers from weaving sections were randomly selected to participate in face-to-face interviews using a structured questionnaire. Noise exposure levels were measured using a noise meter, while hearing loss was assessed using a pure tone audiometer. Logistic regression analysis was conducted to identify factors associated with hearing loss. Among the workers, 88.5% were exposed to noise levels of ≥ 95dB (A), and the prevalence of hearing loss was 71.6%. Factors positively associated with hearing loss included age between 31-50years and over 50years, lack of literacy, experiencing hearing difficulties or earaches, hypertension, and more than 15years of service in the power loom industry. To mitigate noise exposure levels, there is a need for enhanced occupational hazard education and stricter enforcement of safety regulations. Regular audiometry tests should be implemented to monitor hearing threshold shifts. Employers should establish and enforce hearing conservation programs in workplaces where noise exposure exceeds or reaches 95dB (A).

Prevalence of noise-induced health hazards and occupational safety practices among welders in Mysuru city: a cross-sectional study

Background: Occupational exposure to noise is a significant concern in the welding industry, posing potential health hazards to workers. This study aimed to assess the prevalence of noise-induced health hazards, knowledge regarding these hazards, and the practice of preventive measures among welders in Mysuru City. Methods: A cross-sectional study was conducted and data was collected from welders in Mysuru City, including noise exposure levels, perceived stress levels, insomnia prevalence, and demographic characteristics. The association between the number of years of noise exposure and auditory/non-auditory health effects was analysed. Participants' awareness of noise-induced health hazards and the use of protective equipment were also evaluated. Results: The study included male participants, predominantly below 30 years of age, with a majority (74.3%) belonging to the Muslim community. Decreased hearing (11.5%) and sleep disorders (3%) were reported by participants. About half (53.7%) were aware of noise-induced health hazards, with a high usage of safety glasses but limited use of earplugs. Most had exposure to noise for less than 5 years. Moderate levels of perceived stress and low prevalence of insomnia were observed. Significant associations were found between the number of years of noise exposure and both auditory/non-auditory health hazards, as well as between age category and auditory health effects. Conclusions: The study reveals the prevalence of noise-induced health hazards among welders in Mysuru City and highlights the importance of promoting occupational health and safety measures. Raising awareness and encouraging the use of protective measures are crucial to mitigate the adverse effects of noise exposure in the welding industry.

A Study on Assessment of Noise Exposure in the Port Industry: Implications for Occupational Health and Safety

The workplace today is getting more complex, as exposure to chemical, physical, and biological substances at work poses an increasing range of hazards and risks. Industrial hygiene is "that science and art devoted to the anticipation, recognition, evaluation, and control of those environmental factors or stresses arising in or from the workplace". Exposure assessment is the heart of industrial hygiene initiatives, which serves as the foundation for all other functional elements, including medical surveillance, exposure monitoring, engineering controls, administrative controls, and hazardous materials management. Ports are key hubs for worldwide trade, handling a wide range of cargo types with various machinery and equipment. The operational activities within these environments frequently generate high levels of noise, posing a potential hazard to the well-being of the workforce. The purpose of this study is to conduct a comprehensive assessment of noise exposure in the port industry at different locations and to propose appropriate mitigation strategies. The methodology involves the use of sound level measurements using a sound level meter in various port environments. A thorough examination was carried out to identify specific locations for the purpose of conducting noise monitoring. The survey facilitated the quantitative assessment of noise exposure. Based on the findings of this study, necessary recommendations are proposed to minimize noise exposure and protect the well-being of port workers. The insights gained will not just assist port workers but will also contribute to a broader awareness of sustainable and responsible industrial practices. Keywords: Noise exposure, Port industry, Noise assessment, Noise control methods, Personal protective equipment.

Risk Ratio of Noise-Induced Hearing Loss in Mineral Ore Processing Industry Workers

The mining industry employs machines and equipment that generate noise. Noise is an unwanted sound that can cause discomfort to listeners, leading to health issues. One of the health problems caused by noise is Noise-Induced Hearing Loss (NIHL), a hearing impairment resulting from continuous exposure to hazardous noise levels. The Permissible Noise Exposure (PNE) value in the mining industry is set at 85 dB(A). This study aims to assess the risk of noise exposure in relation to the occurrence of NIHL among mineral ore processing workers in the mining industry in Indonesia. The study employs the epidemiological frequency measurement method Relative Risk Ratio (RR). The study categorizes workers into two groups: native mining industry workers and contractor workers in the mining industry. The RR results for each group are 2.68 and 2.76 (RR>1), respectively. These results indicate that the noise-exposed group is at a 2.68-2.76 times higher risk of experiencing NIHL compared to the non-exposed group. Noise exposure in the mining industry poses a high risk of NIHL to workers, necessitating control measures. Control measures involve reducing noise exposure using Personal Protective Equipment (PPE) such as earplugs for workers in noisy areas. The use of earplugs can reduce noise by around 24-32 dB(A). Additionally, some industrial companies conduct awareness programs to encourage workers to use earplugs or other PPE, known as the hearing conservation program.

A Noise-Induced Hearing Loss Prediction Model Based on Asymmetric Convolution for Workers Exposed to Complex Industrial Noise.

Current approaches for evaluating noise-induced hearing loss (NIHL), such as the International Standards Organization 1999 (ISO) 1999 prediction model, rely mainly on noise energy and exposure time, thus ignoring the intricate time-frequency characteristics of noise, which also play an important role in NIHL evaluation. In this study, an innovative NIHL prediction model based on temporal and spectral feature extraction using an asymmetric convolution algorithm is proposed. Personal data and individual occupational noise records from 2214 workers across 23 factories in Zhejiang Province, China, were used in this study. In addition to traditional metrics like noise energy and exposure duration, the importance of time-frequency features in NIHL assessment was also emphasized. To capture these features, operations such as random sampling, windowing, short-time Fourier transform, and splicing were performed to create time-frequency spectrograms from noise recordings. Two asymmetric convolution kernels then were used to extract these critical features. These features, combined with personal information (e.g., age, length of service) in various configurations, were used as model inputs. The optimal network structure was selected based on the area under the curve (AUC) from 10-fold cross-validation, alongside the Wilcoxon signed ranks test. The proposed model was compared with the support vector machine (SVM) and ISO 1999 models, and the superiority of the new approach was verified by ablation experiments. The proposed model had an AUC of 0.7768 ± 0.0223 (mean ± SD), outperforming both the SVM model (AUC: 0.7504 ± 0.0273) and the ISO 1999 model (AUC: 0.5094 ± 0.0071). Wilcoxon signed ranks tests confirmed the significant improvement of the proposed model ( p = 0.0025 compared with ISO 1999, and p = 0.00142 compared with SVM). This study introduced a new NIHL prediction method that provides deeper insights into industrial noise exposure data. The results demonstrated the superior performance of the new model over ISO 1999 and SVM models. By combining time-frequency features and personal information, the proposed approach bridged the gap between conventional noise assessment and machine learning-based methods, effectively improving the ability to protect workers' hearing.

The rate of occupational noise-induced hearing loss among male workers in Israel and implication on hearing surveillance frequency.

To investigate the annual rate of NIHL in Israel, a modern economy with relatively low industrial hazardous noise exposure. To review international protocols of hearing surveillance. To recommend an effective, efficient, hearing screening frequency protocol. A historical cohort study was conducted. Audiometric surveillance data from the Jerusalem occupational medicine registry of male employees in various industries from 2006 to 2017 were used. Mean individual annual threshold shifts simulating 1-8 checkup interval years were calculated. Joinpoint regression analysis was used to assess the interval in which the slope of the calculated ATS variability moderates significantly. A total of 263 noise-exposed workers and 93 workers in the comparison group produced 1913 audiograms for analysis. Among the noise-exposed workers, using the 1-4kHz average, threshold shifts stabilized from 3years onwards at around 1dB per year in all age groups and 0.83dB in the stratum younger than 50years. No enhanced decline was detected in the first years of exposure. Although most countries conduct annual hearing surveillance, hearing threshold shifts of noise-exposed workers become more accurate and show less variability when calculated at 3-year checkup intervals onwards than shorter intervals. Since margins of errors of the test method are much larger than the annual shift found, screening schedule that enables each subsequent test to identify a real deterioration in hearing is necessary. Triennial audiometric screening would be a better surveillance frequency for noise-exposed workers younger than 50years of age in the category of 85-95 dBLAeq,8h without other known risk factors.

Strategic Modelling of Industrial Noise with Limited Input Datav

Historically, strategic modelling of industrial noise exposure on a national scale has taken a wide range of approaches. Where sound emission data of industrial sites are not available, numerous assumptions are often made. These include simplified modelling of industrial sites and adoption of generic sound power levels for different industry types. In most cases such assumptions significantly increase the uncertainty in strategic noise mapping outcomes. This paper presents an alternative approach to strategic modelling of industrial sound which is based on the environmental permitting practice of large industrial sites in England. Drawing on this approach, a cost-effective and scalable modelling procedure has been developed to estimate sound emission levels and radiation patterns of industrial activities accounting for the local context of the site. This paper details the alternative modelling approach along with example prediction outputs. Potential future refinements to improve the modelling accuracy and opportunities to enhance site-specific input data in collaboration with national authorities are also discussed.

Effects of Noise Hazards towards Physiology Especially Heart Rate Performance among Worker in Manufacturing Industry and Their Prevention Strategies: A Systematic Review.

Background:Occupational noise exposure is one of the environmental factors that pose safety and health risks among workers in factories. This systematic review focuses on the activities that cause noise hazards toward workers’ heart rate, other physiological conditions, and strategies to prevent noise exposure in the manufacturing industry.Methods:Through a comprehensive literature review, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane method were used. The appraisal of quality was conducted by using the Critical Appraisal Skills Programme (CASP) to fulfil the selected keywords.Results:Occupational noise exposure not only affects the workers’ most common issues, such as heart rate, but also other physiological factors, such as blood pressure. The outcome showed that different level of continuous noise exposure with high intensity decibels affects the heart rate of the workers. Source, path, receiver was recommended strategies for basic noise prevention in engineering control.Conclusion:Therefore, noise give significant effects towards human workers in related industry. Study related to noise effects towards heart rate performance led to future prevention and innovation.

Application of ISO 1999:2013 (E) model in risk assessment of hearing loss caused by industrial noise

To assess the risk of hearing loss caused by industrial noise exposure of welders and assemblers in a mechanical equipment manufacturing enterprise, and to explore the practical application and possible underestimation of ISO 1999∶2013(E) model. A total of 829 noise-exposed male workers from a mechanical equipment manufacturing enterprise were selected as study subjects. The questionnaire survey was administered, and individual noise exposure level(L_(Aeq.8 h)) and hearing loss level were measured. The risk assessment method of ISO 1999∶2013(E) was used to calculate the change of hearing threshold level and the risk of noise-induced hearing loss. By comparing the median of permanent hearing threshold shift caused by actual noise with the median of ISO1999 predicted value, the reason of the difference between the predicted value of ISO 1999∶2013(E) model and the actual value was analyzed. The L_(Aeq.8 h )was 89.5 dB(A), 77.4%(n=62)of the individual noise exposure levels exceeded 85 dB(A), and 24.6% of the participants(n=829) had different degrees of hearing loss. There was significant difference in hearing loss rate between welding and assembly positions(χ~2=10.07, P<0.01). The risk of noise-induced high-frequency hearing loss of 90% welders was 11.2% at the age of 50, and 14.0% at the age of 60. The risk of noise-induced deafness of 90% welders was 4.3% at the age of 60. The risk of high noise-induced frequency hearing loss of 90% assemblers was at the range of 4.0%-9.0% at the age of 40, 20.8% at the age of 50, and 22.5% at the age of 60. The risk of noise-induced deafness of 90% assemblers was at the range of 1.4%-6.4% at the age of 50, and 9.0% at the age of 60. Compared with actual median of permanent hearing threshold shift, ISO1999∶2013(E) predictions underestimated the median of permanent hearing threshold shift at 10.7 dB. The noise hazards of welding and assembly positions in mechanical equipment manufacturing enterprises are high relatively. ISO1999∶2013(E) can be used to predict the risk of noise-induced hearing loss in workers, but attention should be paid to the risk underestimation of this model.

Occupational noise exposure in Canada's salmonid aquaculture industry

Occupational injuries and diseases are of great concern in aquaculture. The current literature on occupational health and safety in aquaculture have focused on physical hazards such as slips, trips and falls but have ignored the risk of excessive noise exposures. This study aimed to document noise exposures and hazardous noise sources at aquaculture facilities, as well as identify short-term solutions to high exposures experienced by employees. Data was collected at four facilities from different sectors of the aquaculture industry; all focused on salmonids. Noise sources were identified at each facility and analyzed in narrow-band frequency. Noise exposures at each facility were also measured and compared with the regulatory limits of an 8-h time-weighted averaged, A-weighted, 85 dB exposure level. Exposures were highest within the vicinity of machinery rooms of all facilities and during feeding operations at the salmon farm. Workers at the salmon farm were at a much higher risk of excessive noise exposure than employees at the other three facilities due to the tasks performed and the equipment used. The appropriate hearing protection was suggested for each employee to be worn during certain tasks or within the vicinity of noisy machinery on site.

Surveillance of Noise Exposure Level in the Manufacturing Industry - China, 2020.

IntroductionOccupational noise exposure is a widespread issue in the manufacturing industry in China. Since 2019, the National Surveillance System for Occupational Hazards in the workplace was established to understand different occupational hazards, especially occupational noise, in workplaces in China.MethodsBoth environmental and individual noise exposure levels were measured for 19,378 enterprises according to the Work Plan for Surveillance of Occupational Hazards in the Workplace (2020) issued by National Health Commission of the People’s Republic of China. Median and interquartile range (IQR) were calculated to describe the distribution of the noise exposure level by industry classification, enterprise-scale, and ownership type of the enterprise. ResultsOverall, 25.14% of the individual noise exposure samples exceeded the Chinese national standard among the selected enterprises. The overall median of environmental noise exposure level was 82.8 dB(A) in selected enterprises, while the median of individual noise exposure level was 81.3 dB(A). The individual noise exposure level in the manufacture of metal products, manufacture of motor vehicles, mini-sized enterprises, collective enterprises and private enterprises was relatively high.ConclusionOccupational noise is still one of the occupational hazards that cannot be ignored in the manufacturing industry, especially in mini-sized and private enterprises. The risk of noise exposure in the target industry is still high and will pose a threat to the health of workers.

Evaluation of Occupational Noise Exposure in a Plastic Manufacturing Industry: A Case Study

Industrial workers need a safe working environment to ensure their wellbeing is protected while performing tasks. Occupational noise is one of the most prevalent problems in industries due to nature of the industry. Therefore, this paper aimed to evaluate the occupational noise exposure in one of the plastic factories in Klang Valley, Malaysia. Noise measurement has been done in all production lines, crushing department, packaging department and officers’ area. The noise measurements were taken 1 to 3 metres from the source of noise at several points for each line and departments using sound level meter. Average noise level at all measurement location noted LAeq less than 80 dBA, except one point in line B and the crushing area. The packaging department recorded the lowest noise level, with LAeq 64.8 dBA and LAmax of 69.2 dBA. While, the crushing department is the noisiest area in the factory, with LAmax 105 dBA and LAeq 100.9 dBA. The average noise level at majority location in the factory is less than 80 dBA which means it is at a safe range. The workers do not need any personal hearing protection equipment during working, which was according to the Occupational Safety & Health (Noise Exposure) Regulations 2019 noise regulations in Malaysia, except the crushing area only. In conclusion, evaluation of noise exposure in each section can provide a good understanding of the occupational noise level experienced by different workers at different departments. It can help the management to strategize and plan the noise control approach, especially at the area that may have risk of hearing loss for their workers.

Surrounded by Sound: The Impact of Tinnitus on Musicians.

AIM: To investigate the impact of tinnitus on professional musicians in the UK. BACKGROUND: Tinnitus is the experience of sound when an external source is absent, primarily associated with the ageing process, hearing loss, and noise exposure. Amongst populations exposed to industrial noise, noise exposure and noise-induced hearing loss (NIHL) have been found to be the factors most associated with tinnitus. The risk of NIHL amongst professional musicians is greater than that amongst the general population, meaning they may be at increased risk of tinnitus. METHODS: Seventy-four professional musicians completed an online survey involving closed and open-ended questions, and completed the Tinnitus fuctional Index (TFI) questionnaire. Descriptive statistics and thematic analysis of open-ended qualitative responses were used to analyse the data. RESULTS: Three themes were generated from the analysis of the responses to the open-ended questions. These themes were: (1) the impact of tinnitus on the lives of professional musicians, (2) professional musician experience of tinnitus services, support, and hearing health and safety, and (3) the support professional musicians want. The mean global TFI score for professional musicians was 39.05, interpreted as tinnitus being a moderate problem. Comparisons with general population data revealed lower TFI scores for the TFI subscales of ‘sense of control’ and ‘intrusiveness’ for professional musicians and higher for auditory difficulties associated with tinnitus amongst professional musicians. CONCLUSION: Tinnitus can negatively impact on professional musicians’ lives. There is a need for bespoke self-help groups, awareness raising, and education to prevent tinnitus and promote hearing health among musicians.

Clinical and phenotypical features of stroke and forecast in workers under exposure industrial noise

Introduction. The problem of preventing the development of stroke in workers under the influence of harmful production factors is urgent. The aim of the study was to study the characteristics of stroke in men under conditions of industrial noise exposure, to establish the prognostic value in the formation and course of the disease. Material and methods. The study involved 71 men with stroke from 30 to 65 years old, who worked in conditions of industrial noise in the professions of "pilot of civil aviation aircraft" and "adjuster of railway construction machines" for 5 years or more. In order to develop a mathematical model for predicting the development of stroke and to establish an individual risk, a group of 81 men from 30 to 65 years old, working under conditions of exposure to occupational noise for 5 years or more, who had no history of stroke data, were also examined. Using the method of sequential inclusion of the studied risk factors (Forward Stepwise), we selected those that made an independent significant contribution to the development of stroke. Based on the results obtained, a logistic regression formula was created, which determines the likelihood of stroke in men working under conditions of occupational noise. Results. In the group of patients with stroke, persons of middle age were found significantly more often - 53.5%. Ischemic stroke prevailed among clinical forms - 90.1%. Among the risk factors prevailed: arterial hypertension (AH) in 100.0% of cases, dyslipidemia factor in 78.9%, smoking factor in 59.1%. A direct moderate correlation was found between the level of systolic blood pressure, diastolic blood pressure and the index of the NIHSS 1 and NIHSS 2 scales. The influence of the following factors on the development of stroke was established: the level of total cholesterol (β-coefficient=1.0, p=0.001), the presence of atrial fibrillation factor (β-coefficient=2.9, p=0.004), the presence of a factor of alcohol abuse (β-coefficient=1.1, p=0.049), the patient has a diagnosis of grade 2 AH (β-coefficient=13, p=0.041) or a diagnosis of grade 3 hypertension (β-coefficient=1.8, p=0.008). A p(X) value exceeding 0.5 indicates a high risk of developing a stroke. The sensitivity of the proposed method was 76.1%, specificity - 74.1%. Conclusion. The proposed multivariate model is informative for the individual prediction of the development of stroke in men working in conditions of exposure to occupational noise, because reflects the degree of influence of one factor or another on the development of the disease.

Hearing Impairment in Municipal Refuse and Glass Recycling Collection Operatives.

Several international regulatory bodies and researchers have identified employees in the municipal refuse and recycling industry as potentially at risk of noise induced hearing loss. Whilst materials recycling facilities have been subject to research regarding the health effects of hazardous exposures, the roadside recycling collection aspects of the industry has been identified as requiring further investigation. The requirement for characterization of such risk has been increased in the European Union by legislation that has led to increased rates of municipal recycling in the waste disposal industry. In particular, the introduction of glass recycling collection rounds over recent years, alongside long-established refuse collection activities, has given rise to possible further increased levels of industrial noise exposure, beyond that of refuse collection alone. This cross-sectional study describes hearing threshold categorization in 201 male full-time refuse collection workers, most of whom had many years of employment in municipal refuse collection, and all of whom, in the 3-4 years preceding the study, had commenced a work pattern of alternating weeks of municipal glass recycling collection and refuse collection. During this period there was no compulsory use of personal hearing protective equipment. No excess of hearing loss was found in this group, irrespective of years in refuse collection duties or when compared with those studied with additional responsibilities as a driver of refuse wagons (a task not considered to lead to excessive noise exposure). Further research into hearing loss in such employees is merited, given the short time period of exposure to noise from glass collection, but the possible benefit of undertaking detailed full shift personal noise exposure in this group is proposed.

Non-auditory effects of industrial chronic noise exposure on workers; change in salivary cortisol pattern.

SummaryBackgroundNoise has different auditory and non-auditory effects on human. In noisy environments, noise as a non-specific stressor can activates the hypothalamic-pituitary-adrenal axis (HPA, cortisol). The aim of this study was to evaluate the effect of chronic exposure to noise on salivary cortisol on industrial workers.MethodsThis cross-sectional study had a case/control design. 136 male workers (68 workers were exposed to chronic industrial noise, and 68 other workers were exposed to background noise) voluntarily enrolled in the study. The equivalent noise level was measured at workstations and salivary cortisol for both case and control groups was measured at the beginning (6 AM) and also at the end of work shift (4 PM). The amount of change in the average of the values of the two groups were compared with each other.ResultsThe measured Leq8h (equivalent continuous sound level) in case and control groups were 87.43 dB-A and 67.6 dB-A, respectively. Comparison of salivary cortisol levels change in groups shows a significant differences in control groups for salivary cortisol in the morning and in the evening samples (p < 0.05); but not in the case group (p = 0.052). Also, comparison of salivary cortisol levels changes with noise exposure experience in the case subgroups revealed no significant difference (p > 0.05).ConclusionThis study showed that chronic exposure to industrial noise can lead to a change in pattern of salivary cortisol secretion especially in the evening (at the end of the work shift), in a way that instead of its normal decrease, an increase happened.

Association between ABO blood group status and cochlear/neural function: auditory brainstem response findings

Background ABO blood group status may be a risk factor for some diseases, including hearing loss. Individuals with blood group O show a higher prevalence of hearing loss after industrial noise exposure. Group O individuals with normal hearing show reduced amplitudes in otoacoustic emission recordings. Whether blood group status affects auditory brainstem responses (ABR), which reflect cochlear hair cell and auditory nerve bioelectric activity, is unclear. Aims/objectives To compare cochlear and peripheral neural function across ABO blood groups by recording cochlear microphonic (CM) and wave I ABR responses. Material and methods Sixty normal-hearing young adults, with 15 participants from each blood group, completed 70 dB nHL click stimulus ABR measures. CM amplitude, wave I amplitude and wave I latency data were obtained for both ears. One-way ANOVA tests compared results across the ABO groups. Results A statistically significant difference for wave I peak-to-peak amplitudes across the four groups was found. Post-hoc comparisons revealed group O had significantly reduced wave I amplitudes compared to group A participants. A consistent trend of reduced CM amplitudes and prolonged wave I latencies was shown in group O participants. Conclusions and significance Emerging evidence exists that ABO blood group status may influence auditory function.

Practical aspects of occupational risk assessment from industrial noise exposure

Introduction. Today, there is an active application of the occupational risk assessment approach in hygiene practice. In particular, the employer is required to assess the risk of exceeding the production noise limit. The aim of study is to identify issues related to the performance of work on the assessment of occupational risk from noise exposure, based on practical experience. Materials and methods. The assessment of the probability of adverse effects on the health of specific individuals employed in more than a thousand jobs in various branches of Russian industry allows us to identify a number of practical problems. Results. The main problem is the lack of information about the levels of impacting noise that is suitable for constructing subsequent stages of research. One option is the absence of annual monitoring of noise with possible variability in the level of exposure in dynamics. Also, when performing control, there is the use of measuring instruments that do not meet the requirements for ensuring the uniformity of measurements. Often, we are faced with the lack of a fixed identification of workplaces that allows us to track the levels of impacting noise in dynamics. The priority was to support the risk assessment work by conducting control measurements of noise levels with the priority use of personal noise meters to minimize the contribution of uncertainties. Conclusions. The analysis of international experience shows the need to introduce new approaches to monitoring noise levels and the implemented effects of its impact on the part of the hearing organ, including monitoring the accumulated doses, the introduction of a" noise professional route", mandatory audiometry when hiring and annual monitoring of the dynamics of hearing changes; evaluating the effectiveness of the used personal hearing protection equipment (PHPE) in real production conditions.

Dashboard system to track cumulative exposure to sound levels during live music instruction

During music rehearsals, students and teachers are regularly exposed to unsafe sound levels; hearing loss is a major concern among musicians. By providing real time feedback to music instructors, we can persuade them to modify their teaching methods to achieve safe listening conditions. To accomplish this, we created a user-friendly dashboard that displays the cumulative sound energy being collected in real-time. Since there are few standards for limiting music exposure, we used NIOSH standards for industrial noise exposure as the permissible exposure limit (PEL). Circular dials on the dashboard were programmed to display the amount of exposure relative to the PEL. To aid in identifying the type of exposure, each dial represents the amount of sound accumulation in a band of frequencies relative to typical human speech: below (15Hz–85 Hz), at (85Hz–252 Hz), and above (242Hz–24 675 Hz). The dashboard also displays an equalizer representing the instantaneous microphone input. After each session, the cumulative exposure data can be sent out in email format. Inexpensive and convenient to use, this dashboard will enable music instructors to make informed decisions on how to best modify their teaching approaches to reduce the risk of hearing loss.

New Metrics Needed in the Evaluation of Hearing Hazard Associated With Industrial Noise Exposure

To evaluate (1) the accuracy of the International Organization for Standardization (ISO) standard ISO 1999 [(2013), International Organization for Standardization, Geneva, Switzerland] predictions of noise-induced permanent threshold shift (NIPTS) in workers exposed to various types of high-intensity noise levels, and (2) the role of the kurtosis metric in assessing noise-induced hearing loss (NIHL). Audiometric and shift-long noise exposure data were acquired from a population (N = 2,333) of screened workers from 34 industries in China. The entire cohort was exclusively divided into subgroups based on four noise exposure levels (85 ≤ LAeq.8h < 88, 88 ≤ LAeq.8h < 91, 91 ≤ LAeq.8h < 94, and 94 ≤ LAeq.8h ≤ 100 dBA), two exposure durations (D ≤ 10 years and D > 10 years), and four kurtosis categories (Gaussian, low-, medium-, and high-kurtosis). Predicted NIPTS was calculated using the ISO 1999 model for each participant and the actual measured NIPTS was corrected for age and sex also using ISO 1999. The prediction accuracy of the ISO 1999 model was evaluated by comparing the NIPTS predicted by ISO 1999 with the actual NIPTS. The relation between kurtosis and NIPTS was also investigated. Overall, using the average NIPTS value across the four audiometric test frequencies (2, 3, 4, and 6 kHz), the ISO 1999 predictions significantly (p < 0.001) underestimated the NIPTS by 7.5 dB on average in participants exposed to Gaussian noise and by 13.6 dB on average in participants exposed to non-Gaussian noise with high kurtosis. The extent of the underestimation of NIPTS by ISO 1999 increased with an increase in noise kurtosis value. For a fixed range of noise exposure level and duration, the actual measured NIPTS increased as the kurtosis of the noise increased. The noise with kurtosis greater than 75 produced the highest NIPTS. The applicability of the ISO 1999 prediction model to different types of noise exposures needs to be carefully reexamined. A better understanding of the role of the kurtosis metric in NIHL may lead to its incorporation into a new and more accurate model of hearing loss due to noise exposure.