Abstracts

INTRODUCTION

Noise is one of the most common risk factors in work environments. It is the main modifiable cause of hearing loss in adults,⁵5 Dobie RA. The burdens of age-related and occupational noise-induced hearing loss in the United States. Ear Hear.2008;29(4):565-77. DOI:10.1097/AUD.0b013e 31817349ec and ranks third among the occupational hazards that generate the greatest number of years lived with disability.^aa World Health Organization. Global health risks: mortality and burden of disease attributable to selected major risks. Geneva; 2009 [cited 2014 Jun 18]. Available from: http://www.who.int/healthinfo/global_burden_disease/GlobalHealthRisks_report_full.pdf In 2010, in the European Union, 29.0% of workers were exposed to noise for at least a quarter of their daily working hours,^bb The European Foundation for the Improvement of Living and Working Conditions. Fifth European Working Conditions Surveys. Luxembourg; 2012 [cited 2015 Apr 30]. Available from: http://www.eurofound.europa.eu/sites/default/files/ef_files/pubdocs/2011/82/en/1/EF1182EN.pdf while in the United States, between 1999 and 2004, 17.2% were exposed to noise over their entire work shift.¹⁸18 Tak S, Davis RR, Calvert GM. Exposure to hazardous workplace noise and use of hearing protection devices among US workers - NHANES, 1999–2004.Am J Ind Med. 2009;52(5):358-71. DOI:10.1002/ajim.20690

Protecting workers from exposure to noise has been the target of international recommendations, such as ISO-1999^cc International Organization for Standardization. Determination of occupational noise exposure and estimation of noise-induced hearing impairment - ISO 1990:1999. 2.ed. Geneva; 1990 [cited 2015 Apr 30]. Available from: http://www.iso.org/iso/catalogue_detail.htm?csnumber=6759 and specific country regulations. Such recommendations consider factors ranging from the definition of acceptable noise limits to hearing conservation programs, which include the use of hearing protection devices (HPD).^dd Ministério do Trabalho e Emprego. Norma Regulamentadora nº 15: atividades e operações insalubres. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from:http://portal.mte.gov.br/data/files/8A7C816A47594D040147D14EAE840951/NR-15%20(atualizada%202014).pdf^,ee National Institute for Occupational Safety and Health. Criteria for a Recommended Standard: occupational noise exposure: revised criteria 1998. Cincinnati: NIOSH; CDC; 1998 [cited 2014 Jun 18]. Available from: http://www.cdc.gov/niosh/docs/98-126/pdfs/98-126.pdf

The World Health Organization (WHO) estimates that noise-induced hearing loss (NIHL) leading to irreversible cochlear damage accounts for 19.0% of all years lived with disability related to all work-related diseases and illnesses worldwide.³3 Concha-Barrientos M, Nelson DI, Driscoll T, Steenland NK, Punnett L, Fingerhut M, et al. Selected occupational risk factors. In: Ezzati M, Lopez AD, Rodgers A, Murray CJL, editors. Comparative quantification of health risks: global and regional burden of disease attributable to selected major risk factors. Geneva: World Health Organization; 2004. p.1651-801. NIHL can be prevented through collective measures, such as the modification or replacement of machines and equipment, and the use of acoustical barriers, silencers and enclosure, which are recognized as the best and most effective protection measures.^dd Ministério do Trabalho e Emprego. Norma Regulamentadora nº 15: atividades e operações insalubres. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from:http://portal.mte.gov.br/data/files/8A7C816A47594D040147D14EAE840951/NR-15%20(atualizada%202014).pdf When these are not technically feasible, while they are being installed, or used on an emergency basis, individual prevention measures are utilized to reduce the intensity of workers' exposure to noise.^dd Ministério do Trabalho e Emprego. Norma Regulamentadora nº 15: atividades e operações insalubres. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from:http://portal.mte.gov.br/data/files/8A7C816A47594D040147D14EAE840951/NR-15%20(atualizada%202014).pdf^,ff Ministério do Trabalho e Emprego. Norma Regulamentadora Nº 6: Equipamento de Proteção Individual – EPI. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from: http://portal.mte.gov.br/data/files/FF8080814CD7273D014D34C6B18C79C6/NR-06%20(atualizada)%202015.pdf These procedures reduce the risk of NIHL and other potentially adverse effects, such as insomnia, irritability, and increased heart rate and blood pressure.¹²12 Lusk SL, Hagerty BM, Gillespie B, Caruso CC. Chronic effects of workplace noise on blood pressure and heart rate. Arch Environ Health. 2002;57(4):273-81. DOI:10.1080/00039890209601410 In Brazil, Regulatory Norm NR-6^ff Ministério do Trabalho e Emprego. Norma Regulamentadora Nº 6: Equipamento de Proteção Individual – EPI. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from: http://portal.mte.gov.br/data/files/FF8080814CD7273D014D34C6B18C79C6/NR-06%20(atualizada)%202015.pdfestablishes the mandatory use of HPD when sound pressure levels exceed those defined by NR-15,^dd Ministério do Trabalho e Emprego. Norma Regulamentadora nº 15: atividades e operações insalubres. Brasília (DF); 1978 [cited 2015 Apr 28]. Available from:http://portal.mte.gov.br/data/files/8A7C816A47594D040147D14EAE840951/NR-15%20(atualizada%202014).pdf i.e., 85 dB(A) for eight hours a day, or the equivalent.

Although HPD are mandatory, the prevalence of the use of these devices by workers exposed to noise is low: 42.2% of workers in Brazil^gg Ferrite S. Epidemiologia da perda auditiva em adultos trabalhadores [thesis]. Salvador (BA): Instituto de Saúde Coletiva da Universidade Federal da Bahia; 2009 [cited 2015 Apr 28]. Available from: https://repositorio.ufba.br/ri/handle/ri/10892 and 65.7% in the United States.¹⁸18 Tak S, Davis RR, Calvert GM. Exposure to hazardous workplace noise and use of hearing protection devices among US workers - NHANES, 1999–2004.Am J Ind Med. 2009;52(5):358-71. DOI:10.1002/ajim.20690 HPD use is positively associated with certain factors, such as increased noise levels in the workplace,¹⁶16 Raymond DM, Hong O, Lusk SL, Ronis DL. Predictors of hearing protection use for Hispanic and non-Hispanic White factory workers. Res Theory Nurs Pract. 2006;20(2):127-40. DOI:10.1891/rtnp.20.2.127^,1717 Sbihi H, Teschke K, MacNab YC, Davies HW. Determinants of use of hearing protection devices in Canadian lumber mill workers. Ann Occup Hyg. 2010;54(3):319-28. DOI:10.1093/annhyg/mep043 being young,¹⁷17 Sbihi H, Teschke K, MacNab YC, Davies HW. Determinants of use of hearing protection devices in Canadian lumber mill workers. Ann Occup Hyg. 2010;54(3):319-28. DOI:10.1093/annhyg/mep043 being influenced by peers and supervisors,⁹9 Kerr MJ, Lusk SL, Ronis DL. Explaining Mexican American workers' hearing protection use with the health promotion model. Nurs Res. 2002;51(2):100-9. DOI:10.1097/00006199-200203000-00006^,1010 Kim Y, Jeong I, Hong O. Predictors of hearing protection behavior among power plant workers. Asian Nurs Res. 2010;4(1):10-8. DOI:10.1016/S1976-1317(10)60002-3 and, particularly, being male, regardless of occupation.¹⁷17 Sbihi H, Teschke K, MacNab YC, Davies HW. Determinants of use of hearing protection devices in Canadian lumber mill workers. Ann Occup Hyg. 2010;54(3):319-28. DOI:10.1093/annhyg/mep043^,1818 Tak S, Davis RR, Calvert GM. Exposure to hazardous workplace noise and use of hearing protection devices among US workers - NHANES, 1999–2004.Am J Ind Med. 2009;52(5):358-71. DOI:10.1002/ajim.20690

Women's participation in the labor market has increased, especially in economic sectors and occupations traditionally considered to be predominantly male,^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206^,ii Messing K, Östlin P. Gender equality, work and health: a review of the evidence. Geneva: World Health organization; 2006 [cited 2014 Jun 18] Available from:http://www.who.int/gender/documents/Genderworkhealth.pdf?ua= which may have resulted in increased prevalence and/or intensity of exposure to noise. A study of women's working and health conditions using data from the European Union^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206 showed that noise levels in women's work environments are either neglected or poorly monitored, and prevention is not usually targeted by training and information. Such neglect arises from factors related to gender bias and because it occurs in non-industrial activities, such as services – particularly education, accommodation, food and beverage, among others.^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206 The WHO^jj Concha-Barrientos M, Campbell-Lendrum D, Steenland NK. Occupational noise: assessing the burden of disease from work-related hearing impairment at national and local levels. Geneva: World Health Organization; 2004 [cited 2015 Apr 28]. (WHO Environmental Burden of Disease Series, 9). Available from: http://www.who.int/quantifying_ehimpacts/publications/en/ebd9.pdf recommended that studies investigate noise exposure and its distinct effects on men and women, since this is rarely addressed in the literature. Studies on HPD use have not considered gender differences when identifying associated factors. The creation of proper hearing conservation programs cannot disregard information regarding the reasons for HPD use and should take gender differences into account.

This study aimed to analyze whether sociodemographic, occupational, and health-related data are associated with the use of hearing protection devices at work, according to gender.

METHODS

This is a cross-sectional study based on data from a survey on working and health conditions, which used a sample of Salvador, BA, Northeastern Brazil, residents. The city has 2,675,656 residents (2010 census), making it the third most populated in the country. In 2010, it had a Human Development Index (HDI) of 0.759.^kk Instituto Brasileiro de Geografia e Estatística. Cidades. Brasília (DF); 2014 [cited 2014 Jun 18]. Available from: http://www.cidades.ibge.gov.br/xtras/home.php

The original study is a population-based prospective cohort study, which began in 2000, with visits repeated every two years until 2008. The data analyzed came from the fourth phase of the study, which was conducted in 2006, when data on hearing health and noise exposure were obtained. Cluster sampling was conducted in a single stage, with the selection of sub-areas, out of which each family was identified and recruited for the research. Trained field workers used individual questionnaires for interviews during home visits, in order to collect data related to sociodemography, lifestyle, working conditions, and health.

The study population comprises all subjects aged between 18 and 65 years old, who reported having a paid job and being exposed to noise in the workplace – 299 people in total. Noise exposure was defined by positive responses to two questions: "Have you ever worked in a very noisy environment, where you had to shout so that a colleague one meter away could hear you?", which suggests noise exceeding 85 dB(A);¹⁴14 Neitzel R, Daniell W, Sheppard L, Davies H, Seixas N. Comparison of perceived and quantitative measures of occupational noise exposure.Ann Occup Hyg. 2008;53(1):41-54. DOI:10.1093/annhyg/men071 and "Over the last 12 months, have you worked in an environment with that level of noise?".

The outcome variable was the use of hearing protection devices when exposed to workplace noise (yes: regular or frequent use; no: seldom or never). The predictor variables were: 1) sociodemographic: age, ethnicity, marital status, education level, socioeconomic level (based on family assets: low - zero to two items; medium or high - three to nine items); occupational: occupational exposure to noise (in years), average hours of exposure per day, employment relationship (formal, when registered in the worker's Employment Registration Book, or informal, when not), and perceived workplace safety; 3) hearing-related: self-reported hearing loss; tinnitus; previous audiometric tests; and 4) Self-reported health status, which was defined through a response to the question, "Between 0 and 10, what score would you give your health?" (score < 8 = poor, fair, or good; score ≥ 8 = great or excellent).

Regarding perceived workplace safety, responses to the following six questions were analyzed both separately and together: 1) "Are the health and safety of workers sufficiently protected in your workplace?"; 2) "Do your supervisors or bosses encourage you to protect yourself and prevent injuries?"; 3) "Do company owners spend money (invest) to make your workplace safe?"; 4) "Are clear rules established about what you should do to prevent workplace injuries?"; 5) "Is safety more important than production in the company where you work?"; 6) "Are you provided with information on workplace safety?" (adapted from the form used by Garcia et al,⁷7 Garcia AM, Boix P, Canosa C. Why do workers behave unsafely at work? Determinants of safe work practices in industrial workers. Occup Environ Med. 2004;61(3):239-46. DOI:10.1136/oem.2002.005629 2004). Answers "never", "seldom", and "sometimes" were taken as "no", and "frequently" and "always", as "yes". The composite variable regarding perceived workplace safety corresponded to the total sum of scores, counting one point for each "yes" response and zero for each "no", where each answer had the same weight. Categories for analysis were based on tertiles: 0 = poor; 1 to 4 = good; and 5 to 6 = very good.

Overall and specific prevalence of HPD use were estimated according to variable categories. Analyses were carried out separately by gender. The association measure was prevalence ratio (PR), to which 95% confidence intervals based on the Mantel-Haenszel method were used for statistical inference. Analyses were performed using SAS 9.2 statistical software.

The research was approved by the Ethics in Research Committee of the Hospital das Clínicas at the Universidade Federal da Bahia (Protocol 49, June 1^st, 2000). All subjects signed informed consent forms.

RESULTS

The study comprised 299 workers exposed to workplace noise out of the total cohort subjects (n = 2,429). Study subjects were more commonly young (76.6%), black (65.4%), in formal jobs (61.4%), male (60.9%) adults with at least high school education (67.6%). The majority had been exposed to occupational noise for at least five years (60.2%), eight hours a day or less (78.9%). Women exposed to occupational noise were less likely to be black (p = 0.0029), had more schooling (p = 0.0004), and were less likely to report previous audiometric tests (p < 0.0001). Men and women perceived workplace safety differently: 45.4% of the women considered their workplace safety to be "poor", whereas only 20.5% men (p < 0.0001) expressed this opinion. There were no gender differences for the remaining variables.

Prevalence for use of HPD by workers exposed to noise was 44.5% (95%CI 38.9;50.1). Patterns of HPD use differed between genders; 59.3% of men and 21.4% of women reported HPD use (PR = 2.78; 95%CI 1.92;4.01). Regarding sociodemographic factors (Table 1), HPD use was associated with medium/high socioeconomic levels (compared to low) and with having had previous audiometric tests (compared to no tests) for men (Table 2). For women who perceived workplace safety as "very good" the prevalence of HPD use was three times greater than for those who reported working under "poor" safety conditions (Table 3). The influence of supervisors in preventing workplace injuries, the existence of clear rules to prevent them, and being informed about workplace safety were positively associated with HPD use in women.

DISCUSSION

Less than half of the workers exposed to noise used HPD; this was almost three times more common among men than women. The perceived degree of safety was associated with HPD use among women, with greater use related to greater perception of an unsafe work environment. Use of HPD was more likely to be reported by women who mentioned that they had committed supervisors, clearly stated safety rules, and access to safety information. Among men, medium or high socioeconomic levels and previous audiometric tests were associated factors.

Our estimated prevalence of HPD use is close to the finding of 41.4% from a study in the United States, based on data from 1981 to 1983, by the National Institute for Occupational Safety and Health (NIOSH).⁴4 Davis RR, Sieber WK. Hearing protector use in noise-exposed workers: a retrospective look at 1983. AIHA J.2002;63(2):199-204. DOI:10.1080/15428110208984705 From 1999 to 2004, results from the National Health and Nutrition Examination Survey (NHANES) showed a prevalence of 65.7%.¹⁸18 Tak S, Davis RR, Calvert GM. Exposure to hazardous workplace noise and use of hearing protection devices among US workers - NHANES, 1999–2004.Am J Ind Med. 2009;52(5):358-71. DOI:10.1002/ajim.20690 Despite evidence of a positive trend in the use of hearing protection in the United States, these results still indicate that one out of three workers exposed to noise did not use HPD.

Less HPD use by women – even when exposed to workplace noise – demonstrates that they are less protected, and more vulnerable, with increased risk of NIHL, compared with men. This gender bias merits attention. This finding confirms results from European studies, which found negligence in monitoring and prevention that demonstrated the invisibility of occupational noise exposure among women. Women have taken up jobs in industries that, although less obviously linked to NIHL risk factors, have been found to have high noise levels.^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206This has been observed in countries with more advanced health regulations concerning labor-related health: in the United States, HPD use among women exposed to noise was 50.7%, compared with 68.9% among men.¹⁸18 Tak S, Davis RR, Calvert GM. Exposure to hazardous workplace noise and use of hearing protection devices among US workers - NHANES, 1999–2004.Am J Ind Med. 2009;52(5):358-71. DOI:10.1002/ajim.20690 The more frequent use of hearing protection by men may be related to the job tasks and industries most frequently performed by men, in which high noise exposure levels are common, such as mining, construction, and manufacturing.³3 Concha-Barrientos M, Nelson DI, Driscoll T, Steenland NK, Punnett L, Fingerhut M, et al. Selected occupational risk factors. In: Ezzati M, Lopez AD, Rodgers A, Murray CJL, editors. Comparative quantification of health risks: global and regional burden of disease attributable to selected major risk factors. Geneva: World Health Organization; 2004. p.1651-801. Future analyses must consider specific occupations and industries, since these are important factors in noise exposure. This was not possible here, due to a small study sample composed of a general worker population.

In our study, factors associated with HPD use differed according to gender. Higher socioeconomic levels and having previous audiometric tests seem to favor the use of individual protection among men; among women, however, correlated factors were how their workplace was organized, namely their perception that it had a safety climate. Work in Brazil's manufacturing industry is relatively well paid, and is known to have high levels of exposure to loud noises.²2 Cavalcante F, Ferrite S, Meira TC. Exposição ao ruído na indústria de transformação no Brasil. Rev CEFAC. 2013;15(5):1364-70. DOI:10.1590/S1516-18462013005000021 This association may arise from a more hazardous work environment for NIHL, a more extensive adoption of protection measures, closer supervision of HPD use or compliance with legal regulations to protect workers' health.

Previous audiometric testing seems to favor the use of HPD among men, which may also indicate better compliance to regulations, given presumably greater workplace noise. In Brazil, audiometric tests are mandatory for workers exposed to noise levels that exceed the legally permitted limits. Workers are also required to join hearing conservation programs.^ll Ministério do Trabalho e Emprego, Secretaria de Saúde e Segurança no Trabalho. Portaria nº 19 de 9 de abril de 1998. Diretrizes e parâmetros mínimos para avaliação a acompanhamento da audição em trabalhadores expostos a níveis de pressão sonora elevados. Diario Oficial Uniao. 22 abr 1998; Seção 1:64-6. However, Lusk et al¹¹11 Lusk SL, Hong OS, Ronis DL, Eakin BL, Kerr M, Early MR. Effectiveness of an intervention to increase construction workers' use of hearing protection. Hum Factors. 1999;41(3):487-94. DOI:10.1518/001872099779610969 and Kim et al¹⁰10 Kim Y, Jeong I, Hong O. Predictors of hearing protection behavior among power plant workers. Asian Nurs Res. 2010;4(1):10-8. DOI:10.1016/S1976-1317(10)60002-3 did not find that HPD use was associated with previous audiometric tests in the United States and South Korea, respectively.

The association between the positive aspects of perceived workplace safety and HPD use among women corroborates the findings of Edelson et al⁶6 Edelson J, Neitzel R, Meischke H, Daniell W, Sheppard L, Stover B, et al. Predictors of hearing protection use in construction workers. Ann Occup Hyg. 2009;53(6):605-15. DOI:10.1093/annhyg/mep039 for workers of both genders. Women are more inclined towards sociability, which also applies to their workplaces, and are more influenced by recommendations to protect their health. Further, they are more likely to report health problems and more committed to healthy behavior, such as checkups, treatment compliance and other recommendations that promote their health.¹³13 Machin R, Couto MT, Silva GSN, Schraiber LB, Gomes R, Figueiredo WS, et al. Concepções de gênero, masculinidade e cuidados em saúde: estudo com profissionais de saúde da atenção primária. Cienc Saude Coletiva. 2011;16(11):4503-12. DOI:10.1590/S1413-81232011001200023 This may arise from behavioral and cultural patterns, as well as from awareness and commitment to their role as caregiver, particularly of children.⁸8 Gustafson PE. Gender differences in risk perception: theoretical and methodological perspectives. Risk Anal. 1998;18(6):805-11. DOI:10.1111/j.1539-6924.1998.tb01123.x It may also be a result of specific characteristics related to jobs and industries where women are usually engaged, which may have affected our findings. However, the small numbers in this study did not allow for further analysis.

The differences between men and women must be understood from a gender perspective. Women are affected by discrimination at work, earn lower wages than men (even when occupying similar jobs), face obstacles which limit their prospects of promotion, are less likely to be union members, and have less visibility and political capital in decision-making.ⁱi Messing K, Östlin P. Gender equality, work and health: a review of the evidence. Geneva: World Health organization; 2006 [cited 2014 Jun 18] Available from:http://www.who.int/gender/documents/Genderworkhealth.pdf?ua= Women are gradually achieving jobs in traditionally male areas, and have thus become increasingly involved in new production spaces.ⁱi Messing K, Östlin P. Gender equality, work and health: a review of the evidence. Geneva: World Health organization; 2006 [cited 2014 Jun 18] Available from:http://www.who.int/gender/documents/Genderworkhealth.pdf?ua= However, exposure to workplace hazards and preventive programs tend to be framed and analyzed from a male perspective. Hazards and their control are therefore frequently neglected or forgotten when they affect women.^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206 A European Union review of women's working conditions^hh European Agency for Safety and Health at Work. New risks and trends in the safety and health of women at work. Luxembourg: Publications Office for the European Union; 2013. DOI:10.2802/69206 demonstrated noise exposure in job posts not traditionally recognized as "hazardous" for men, such as education, health care and hospitality. It was also noted that women usually receive less training and fewer recommendations regarding HPD use than men.

Although age,¹¹11 Lusk SL, Hong OS, Ronis DL, Eakin BL, Kerr M, Early MR. Effectiveness of an intervention to increase construction workers' use of hearing protection. Hum Factors. 1999;41(3):487-94. DOI:10.1518/001872099779610969^,1616 Raymond DM, Hong O, Lusk SL, Ronis DL. Predictors of hearing protection use for Hispanic and non-Hispanic White factory workers. Res Theory Nurs Pract. 2006;20(2):127-40. DOI:10.1891/rtnp.20.2.127^,1717 Sbihi H, Teschke K, MacNab YC, Davies HW. Determinants of use of hearing protection devices in Canadian lumber mill workers. Ann Occup Hyg. 2010;54(3):319-28. DOI:10.1093/annhyg/mep043 education,⁹9 Kerr MJ, Lusk SL, Ronis DL. Explaining Mexican American workers' hearing protection use with the health promotion model. Nurs Res. 2002;51(2):100-9. DOI:10.1097/00006199-200203000-00006 and self-reported hearing loss¹⁶16 Raymond DM, Hong O, Lusk SL, Ronis DL. Predictors of hearing protection use for Hispanic and non-Hispanic White factory workers. Res Theory Nurs Pract. 2006;20(2):127-40. DOI:10.1891/rtnp.20.2.127 have been found in association with HPD use, our results did not show this. This discrepancy may arise from methodological differences, particularly the heterogeneity of industries and jobs within the population studied.

As a tool for occupational noise control, the use of HPD is limited and not very effective, compared with collective interventions, which work independently of individual discretion or access to equipment for worker protection, and do not cause the discomfort or annoyance associated with anatomical or ergonomic adjustment difficulties. More appropriate recommendations are the control of noise emissions at their principal sources and of noise propagation in the workplace, and the implementation of actions to reduce worker exposure.¹⁵15 Nelson DI, Nelson RY, Concha-Barrientos M, Fingerhut M. The global burden of occupational noise-induced hearing loss. Am J Ind Med. 2005;48(6):446-58. DOI:10.1002/ajim.20223 However, such initiatives are not always feasible, causing the widespread use of HPD, given their low cost, reasonable effectiveness, and easy access.¹⁰10 Kim Y, Jeong I, Hong O. Predictors of hearing protection behavior among power plant workers. Asian Nurs Res. 2010;4(1):10-8. DOI:10.1016/S1976-1317(10)60002-3

This research presents limitations related to statistical power, because of its small sample size. This is aggravated by a need to take into account gender, although it did enable the identification of distinct occupational factors between men and women. Given the few observations, it was not possible to include multinomial variables in the analysis, such as jobs or industries, nor to perform a more in-depth treatment of potential confounding variables or effect modifiers. Furthermore, our data comes from a study carried out with a different aim, thus reducing the scope of the available descriptor variables and other important causal factors, such as exposure intensity level. The HPD use did not take into account duration, or quality of adjustment, comfort, and level of protection. The advantages of this study include its relevance for prevention and its originality, because it did not merely describe the occurrence of clinical diagnoses in populations. Rather it focused on popularity, access, and compliance to a protection recommended against one of the most common labor-related illnesses, NIHL, which is responsible for a significant number of sensory disability cases worldwide. Since HPD use is mandatory for workers exposed to noise, the results of this study also demonstrate the extent of regulatory compliance. Organizational factors regarding risk management in work environments, such as the perceived safety investigated in this study, have not been sufficiently explored.

There is gender bias regarding protection against exposure to noise, namely in HPD use, which is less favorable to women than men. Gender, therefore, must be considered in hearing conservation programs. Although perceived safety and some of its components have only been associated with use of HPD among women, interventions based on these results may also contribute to the more frequent use of hearing protection devices by men, once such interventions are adjusted for male characteristics. Contributions can therefore be made to prevent the onset or worsening of NIHL, while better conditions for workers' hearing health can be promoted.

REFERENCES

Publication Dates

History