Productivity Burden of Occupational Noise-Induced Hearing Loss in Australia: A Life Table Modelling Study

Sources of noise exposure across Australian workplaces: cross-sectional analysis and modelling the impact of a targeted noise-source reduction initiative

CONTEXT

Workplace noise regulations and guidance follow the hierarchy of control model that prioritizes eliminating or reducing noise at its source.

OBJECTIVES

To determine the main sources of workplace noise exposure in the Australian working population and estimate the reduction of workers exposed over the noise limit (LAeq,8h > 85 dB) if noise levels of specific tools or equipment were reduced by 10 dB.

METHODS

Information on the tools used and tasks performed during each participant's last working shift was collected from 4,977 workers via telephone survey. Using a predetermined database of task-based noise levels, partial noise exposures (Pa2h) were determined for each noisy activity performed by the workers and their daily noise exposure level (LAeq,8h) was estimated. Partial exposures were categorized into 15 tool/task groups and the tally, average, and sum (Pa2h) for each group were calculated. The impacts of 5 different scenarios that simulated a reduction of 10 dB in noise emissions for specific tool groups were modelled.

RESULTS

Powered tools and equipment were responsible for 59.3% of all noise exposure (Pa2h); vehicles for 10.6%; mining, refineries, and plant equipment for 5.1%; and manufacturing and food processing for 4.2%. Modelling demonstrated that a 10 dBA noise-level reduction of all powered tools and equipment would lead to a 26.4% (95% confidence interval: 22.7% to 30.3%) reduction of workers with an LAeq,8h > 85 dB. This could represent over 350,000 Australian workers no longer exposed above the workplace limit daily.

CONCLUSIONS

A universal reduction of 10 dB to power tools and equipment would substantially reduce the future burden of hearing loss, tinnitus, workplace injuries, and other health effects. Initiatives to reduce the noise emissions of specific powered tool groups are warranted.

Advancing noise management in aviation: Strategic approaches for preventing noise-induced hearing loss

As urbanization and population growth escalate, the challenge of noise pollution intensifies, particularly within the aviation industry. This review examines current insights into noise-induced hearing loss (NIHL) in aviation, highlighting the risks to pilots, cabin crew, aircraft maintenance engineers, and ground staff from continuous exposure to high-level noise. It evaluates existing noise management and hearing conservation strategies, identifying key obstacles and exploring new technological solutions. While progress in developing protective devices and noise control technologies is evident, gaps in their widespread implementation persist. The study underscores the need for an integrated strategy combining regulatory compliance, technological advances, and targeted educational efforts. It advocates for global collaboration and policy development to safeguard the auditory health of aviation workers and proposes a strategic framework to enhance hearing conservation practices within the unique challenges of the aviation sector.

The Australian Eye and Ear Health Survey (AEEHS): Study protocol for a population-based cross-sectional study

INTRODUCTION

Vision and hearing impairments are highly prevalent and have a significant impact on physical, psychological and social wellbeing. There is a need for accurate, contemporary national data on the prevalence, risk factors and impacts of vision and hearing loss in Australian adults.

OBJECTIVES

The Australian Eye and Ear Health Survey (AEEHS) aims to determine the prevalence, risk factors and impacts of vision and hearing loss in both Aboriginal and Torres Strait Islander and non-Indigenous older adults.

METHODS AND ANALYSIS

The AEEHS is a population-based cross-sectional survey which will include 5,000 participants (3250 non-Indigenous aged 50 years or older and 1750 Aboriginal and Torres Strait Islander people aged 40 years or older) from 30 sites covering urban and rural/regional geographic areas, selected using a multi-stage, random cluster sampling strategy. Questionnaires will be administered to collect data on socio-demographic, medical, ocular and ontological history. The testing battery includes assessment of blood pressure, blood sugar, anthropometry, visual acuity (presenting, unaided, pinhole and best-corrected), refraction, tonometry, slit lamp and dilated eye examination, ocular imaging including optical coherence tomography (OCT), OCT-angiography and retinal photography, and automated visual fields. Audiometry, tympanometry and video otoscopy will also be performed. The primary outcomes are age-standardised prevalence of cause-specific vision and hearing impairment. Secondary outcomes are prevalence of non-blinding eye diseases (including dry eye disease), patterns in health service utilisation, universal health coverage metrics, risk factors for vision and hearing impairment, and impact on quality of life.

An Exploratory Study on Self-Reported Auditory Symptoms and Hearing Loss among Workers in a Small-Scale LPG Plant

Background

Occupational noise is considered a factor contributing to acquired hearing loss (HL) in adults. Frequent noise exposure can cause cochlear damage, leading to sensorineural HL, tinnitus, vertigo, and other non auditory effects as well. Although it is well known that liquefied petroleum gas (LPG) plants in India have become a workplace source for occupational noise pollution exposure, there are not many studies that probe into the auditory effects of workplace noise in LPG plants.

Aim

The study aims to document HL and self reported otological symptoms in employees with occupational noise exposure at a typical LPG plant in a suburban location in India. 53 employees who reported workplace noise exposure were assessed for HL and self reported auditory symptoms.

Method

Self reported symptoms were collected using a custom made case history questionnaire, and auditory sensitivity was measured using air conduction audiometers.

Results

Among the 53 participants, 27 tested positive for HL. A mild degree of HL was frequently observed, followed by a moderate and severe degree of HL. In the self reported otological complaints reported by 31 participants, HL and aural fullness were the most commonly reported auditory symptoms. Additionally, the use of ear protection devices and hearing conservation practices among the participants were poor.

Conclusion

Hearing loss and self-reported auditory symptoms were present in the study group indicating the effect of occupational noise in the auditory system.

Assessing the Usefulness of Mobile Apps for Noise Management in Occupational Health and Safety: Quantitative Measurement and Expert Elicitation Study

Background

Overexposure to occupational noise can lead to hearing loss. Occupational noise mapping is conventionally performed with a calibrated sound level meter (SLM). With the rise of mobile apps, there is a growing number of SLM apps available on mobile phones. However, few studies have evaluated such apps for accuracy and usefulness to guide those with occupational noise detection needs in selecting a quality app.

Objective

The purpose of this study was to evaluate the accuracy and usefulness of SLM mobile apps to guide workplace health and safety professionals in determining these apps' suitability for assessing occupational noise exposure.

Methods

The following three iOS apps were assessed: the NIOSH (National Institute for Occupational Safety and Health) Sound Level Meter, Decibel X, and SoundMeter X apps. The selected apps were evaluated for their accuracy in measuring sound levels in low-, moderate-, and high-noise settings within both simulated environments and real-world environments by comparing them to a conventional SLM. The usefulness of the apps was then assessed by occupational health specialists using the Mobile App Rating Scale (MARS).

Results

The NIOSH Sound Level Meter app accurately measured noise across a range of sound levels in both simulated settings and real-world settings. However, considerable variation was observed between readings. In comparison, the Decibel X and SoundMeter X apps showed more consistent readings but consistently underestimated noise levels, suggesting that they may pose a risk for workers. Nevertheless, none of the differences in sound measurements between the three apps and the conventional SLM were statistically significant (NIOSH Sound Level Meter: P=.78; Decibel X: P=.38; SoundMeter X: P=.40). The MARS scores for the three apps were all above 3.0, indicating the usefulness of these apps.

Conclusions

Under the conditions of this study, the NIOSH Sound Level Meter app had equivalent accuracy to the calibrated SLM and a degree of usefulness according to the MARS. This suggests that the NIOSH Sound Level Meter app may be suitable for mapping noise levels as part of a monitoring strategy in workplaces. However, it is important to understand its limitations. Mobile apps should complement but not replace conventional SLMs when trying to assess occupational noise exposure risk. Our outcomes also suggest that the MARS tool may have limited applicability to measurement-based apps and may be more suited to information-based apps that collect, record, and store information.

A workers' health surveillance online training programme for occupational physicians

BACKGROUND

To support occupational physicians (OPs) in the implementation of workers' health surveillance (WHS), a training programme was developed.

AIMS

(i) To evaluate the effects of a WHS training programme for OPs on knowledge, self-efficacy and skills to implement WHS. (ii) To evaluate to what extent a WHS training programme is acceptable and feasible for implementation in practice.

METHODS

A single-blinded randomized controlled trial with waiting-list control group was used. The WHS training programme consisted of an e-learning and a 4.5-h online training session. OPs completed a knowledge test (0-8), self-efficacy questionnaires on knowledge and skills (6-60), and vignette assignments (0-16) to measure skills. OPs completed the questionnaires, either before and after the WHS training programme (intervention group), or before the training programme (control group) while receiving the training programme after the waiting period. All OPs completed questionnaires about the training's acceptability, and feasibility for implementation in practice. ANCOVA and Poisson regression analyses were conducted.

RESULTS

The self-efficacy score (M = 44.1 versus M = 37.2) (P < 0.001) and skills score (M = 9.6 versus M = 8.3) (P < 0.05) of OPs in the training group (N = 16) were higher than the control group (N = 23). No effect was found on knowledge. Evaluation of acceptability and feasibility showed that 21 (58%) OPs were very satisfied with the training part on initiating WHS, and 29 (85%) would recommend the WHS training programme to colleagues.

CONCLUSIONS

This WHS training programme has a positive effect on self-efficacy and skills of OPs to implement WHS, and may be acceptable and feasible to implement in practice.

Occupational Risk Factors by Sectors: An Observational Study of 20,000 Workers

OBJECTIVE

We aimed to assess the prevalence of exposure by sector and the sectors of activity most exposed to each exposure, using routine occupational health data, and to quantify the risk of being exposed.

METHOD

Occupational risk factors were assessed by workers followed by the Occupational Health Service of Cher, using self-reported questionnaires. The sectors of activity were grouped into seven sectors, and the risks were grouped into six occupational exposure groups. Comparisons were made using the Chi-squared test and Cramer's V, and the odds ratios were calculated by using logistic regression.

RESULTS

We included 19,891 workers. The construction sector had the highest prevalence (p < 0.05 vs. all other sectors) of exposure to physical (76%) and biomechanical factors (82%), as well as chemical risks (75%). Human health and social work was the sector with the highest prevalence of exposure to biological factors (69%), psychosocial factors (90%), and atypical working hours (61%). With workers from administrative and support sectors as the reference, construction workers had more chance of declaring exposure to physical factors (OR = 3.28, 95%CI = 2.89 to 3.72), biomechanical factors (1.82, 1.58 to 2.09), and chemical agents (3.83, 3.38 to 4.33). Workers from the human health and social sectors had more chance of being exposed to biological agents (13.4, 11.9 to 15.2), atypical working hours (1.93, 1.75 to 2.14), and psychosocial factors (2.74, 2.38 to 3.16).

CONCLUSION

Psychosocial risk factors were commonly reported in all sectors. Workers in the construction, human health, and social sectors seem to report more exposures than those in other sectors. The analysis of occupational exposures is a necessary basis to build an efficient preventive strategy for occupational health.

Presenteeism and noise perception at work: a cross-sectional study using association analysis

BACKGROUND

Presenteeism refers to the presence of a worker at work with reduced performance due to illness, and it is a common public health problem. Exposure to noise during production processes brings risk to workers' health.

OBJECTIVE

To analyze the health profile of workers in the automotive industry and identify the association between noise perception and presenteeism among workers in the Brazilian automotive industry.

DESIGN AND SETTING

This was a cross-sectional study utilizing a case study design analyzing the automotive industry in the interior of São Paulo state, Brazil.

METHODS

This study included 306 workers using the Presenteeism Work Limitations Questionnaire protocol. Multiple logistic regression was used for data analysis.

RESULTS

Male workers with reports of headache, tension, and limited well-being at work, having perceived that noise exposure interferes with productivity, showed a positive association with the occurrence of presenteeism. Physical demand had the highest score in terms of interfering with the presenteeism index.

CONCLUSION

Workers' perceptions of noise were associated with presenteeism.

Pre-employment hearing threshold levels of 59,601 Australian male coal miners compared to an otologically normal international male population (ISO7029:2019)

OBJECTIVE

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.

DESIGN

This was an observational, retrospective, repeated cross-sectional study.

STUDY SAMPLE

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.

RESULTS

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.

CONCLUSION

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.

A cost-benefit analysis of COVID-19 lockdowns in Australia

This paper conducts a cost–benefit analysis of Australia’s Covid-19 lockdown strategy relative to pursuit of a mitigation strategy in March 2020. The estimated additional deaths from a mitigation strategy are 11,500 to 40,000, implying a Cost per Quality Adjusted Life Year saved by locking down of at least 11 times the generally employed figure of $100,000 for health interventions in Australia. The lockdowns do not then seem to have been justified by reference to the standard benchmark. Consideration of the information available to the Australian government in March 2020 yields a similar ratio and therefore the same conclusion that lockdown was not warranted. If Australia experiences a new outbreak, and cannot contain it without resort to a nationwide lockdown, the death toll from adopting a mitigation strategy at this point would be even less than had it done so in March 2020, due to the vaccination campaign, lessons learned since March 2020, and because the period over which the virus would then inflict casualties would now be much less than the period from March 2020. This would favour a mitigation policy even more strongly than in March 2020. This approach of assessing the savings in quality adjusted life years and comparing them to a standard benchmark figure ensures that all quality adjusted life years saved by various health interventions are treated equally, which accords with the ethical principle of equity across people.

The efficacy of earplugs at a major hazard facility

At a major hazard facility, cases of occupational noise-induced hearing loss have occurred despite the use of hearing protection devices. Preliminary measurements of personal attenuation ratings (PAR) suggested that earplugs may not achieve the attenuation implied by their Australian SLC80 Class designation in field-use conditions. We examined the relationship between PAR and the SLC80 classification for earplugs, as a good understanding of the attenuation provided by earplugs under normal field-use conditions, rather than in laboratory settings, is vital to their effective use as a control measure for noise exposure. A cross-sectional study was performed with 65 volunteers. Participants were recruited from Operations and Maintenance Technicians at the major hazard facility. The participants had their PARs checked with different earplug types using the 3 M™ E-A-Rfit™ system. We examined the PARs measured and also assigned a 'pass' or 'fail' rating depending on whether the earplug achieved 22 dB attenuation. 22 dB attenuation for 80% of users is the minimum to meet the definition for Australian SLC80 Class 4 hearing protection. None of the earplug types achieved 22 dB attenuation for 80% of users when tested in field-use conditions. There were statistically significant differences in the frequency of achieving a 'Pass', and in PAR, depending on earplug type. Roll-down foam earplugs may provide superior attenuation compared to pre-moulded earplugs. Earplugs are unlikely to achieve the attenuation found in laboratory conditions during field-use. Personalised selection of hearing protection devices based on fit-testing results should be encouraged.

Attitudes towards Safe Listening Measures in Entertainment Venues: Results from an International Survey among Young Venue-Goers

BACKGROUND

Sustained exposure to excess noise in recreational settings is among the main causes of hearing loss among young adults worldwide. Within a global effort to develop standards for safe listening in entertainment venues, this study aims at identifying modifiable factors (knowledge, attitudes, and beliefs), which can hinder or facilitate the acceptance of safe listening measures in public venues among young venue-goers.

METHODS

An online questionnaire was developed inspired by the Health Belief Model. It was divided into five sections: (i) socio-demographics (ii) listening habits, (iii) experiences with loud music, (iv) knowledge, attitudes, and beliefs, and (v) willingness to change. Participants were recruited through social media.

RESULTS

2264 individuals aged 16-35 completed the questionnaire. Most visited entertainment venues relatively infrequently, with the majority of them only visiting once per month or less. Nevertheless, most reported having experienced the negative consequences of listening to loud music. Overall, most people were favorable towards preventive measures, especially quiet areas.

CONCLUSION

Our findings stress the urge to address the issue of safe listening in public venues and support an approach based on the introduction of standards. Moreover, they provide us with information on key factors to be considered when introducing and communicating preventive measures in public entertainment venues.