Os equipamentos de proteção individual devem ser utilizados após a implantação de medidas administrativas, de medidas de proteção coletiva, alterações de projeto ou em situações de emergência. Podem ser considerados como a última barreira entre um trabalhador e uma condição perigosa. A seleção destes equipamentos deve ser cuidadosa e este trabalho objetivou a criação de um programa de computador para auxiliar os profissionais responsáveis pelo processo de seleção de protetores auditivos, uma posterior comparação entre as saídas do programa com os equipamentos disponibilizados para os trabalhadores das empresas analisadas e uma análise crítica dos documentos obtidos das empresas. Foi efetuada uma revisão bibliográfica das metodologias de seleção de protetores auditivos, criando-se um fluxograma decisório, com pontos de interação com o usuário para a coleta de dados. Foram utilizados programas de prevenção de riscos ambientais de 7 empresas de mineração, identificadas as atividades cujos níveis de ruído se encontravam acima dos limites legais permitidos, determinando-se a necessidade ou não da utilização de protetores auditivos. Os dados foram introduzidos no programa, obtendo-se uma lista de equipamentos adequados para cada atividade selecionada. Compararam-se os equipamentos selecionados pelo programa com os equipamentos oferecidos pelas empresas, identificando-se as vantagens do programa. Observou-se também a baixa qualidade dos documentos emitidos pelas empresas que, em geral, não atenderam aos requisitos mínimos dispostos na legislação. Verificou-se que, quando selecionados corretamente, os equipamentos selecionados pelas empresas estavam contidos na lista de saída do programa, concluindo-se que o programa permitiu maior flexibilidade na escolha dos equipamentos de proteção auditiva, podendo se refletir em vantagens ergonômicas para os trabalhadores e econômicas para as empresas. / Personal protective equipment should only be used after engineering, administrative and work practices or in emergency situations. For this reason, PPE may be considered the last line of defense between workers and a hazardous situation. This work aims to create computer software to assist safety personnel in the PPE selection process, to compare the results produced by this software with the equipment provided by the companies when data from exposures were input and a critical analysis of the documents provided by the companies. A search for the PPE selection methods was conducted, generating a flowchart for hearing protector selection that was implemented in a web site. Data from risk management programs of 7 Brazilian mining companies were used as input to the software once the high risk of noise exposure activities were identified. A list of adequate equipment was then generated by the software and this list was compared to the list of equipments provided by each company. After a critical analysis the software advantages were found to be the higher flexibility in the choice of hearing protectors brought by the much larger list of adequate equipment. Additional advantages include the smaller amount of time spent looking for the correct choice and the ability to provide multiple choices of equipment for workers to choose from, which increases the comfort and thus the compliance to the PPE program. The quality of the documents provided by the companies was found to be low and lacking several requirements of Brazilian Law. The created software was found to be a useful tool, further testing and improvements are needed to increase its usability and to consolidate it as an asset to health and workplace safety professionals.

Os equipamentos de proteção individual devem ser utilizados após a implantação de medidas administrativas, de medidas de proteção coletiva, alterações de projeto ou em situações de emergência. Podem ser considerados como a última barreira entre um trabalhador e uma condição perigosa. A seleção destes equipamentos deve ser cuidadosa e este trabalho objetivou a criação de um programa de computador para auxiliar os profissionais responsáveis pelo processo de seleção de protetores auditivos, uma posterior comparação entre as saídas do programa com os equipamentos disponibilizados para os trabalhadores das empresas analisadas e uma análise crítica dos documentos obtidos das empresas. Foi efetuada uma revisão bibliográfica das metodologias de seleção de protetores auditivos, criando-se um fluxograma decisório, com pontos de interação com o usuário para a coleta de dados. Foram utilizados programas de prevenção de riscos ambientais de 7 empresas de mineração, identificadas as atividades cujos níveis de ruído se encontravam acima dos limites legais permitidos, determinando-se a necessidade ou não da utilização de protetores auditivos. Os dados foram introduzidos no programa, obtendo-se uma lista de equipamentos adequados para cada atividade selecionada. Compararam-se os equipamentos selecionados pelo programa com os equipamentos oferecidos pelas empresas, identificando-se as vantagens do programa. Observou-se também a baixa qualidade dos documentos emitidos pelas empresas que, em geral, não atenderam aos requisitos mínimos dispostos na legislação. Verificou-se que, quando selecionados corretamente, os equipamentos selecionados pelas empresas estavam contidos na lista de saída do programa, concluindo-se que o programa permitiu maior flexibilidade na escolha dos equipamentos de proteção auditiva, podendo se refletir em vantagens ergonômicas para os trabalhadores e econômicas para as empresas. / Personal protective equipment should only be used after engineering, administrative and work practices or in emergency situations. For this reason, PPE may be considered the last line of defense between workers and a hazardous situation. This work aims to create computer software to assist safety personnel in the PPE selection process, to compare the results produced by this software with the equipment provided by the companies when data from exposures were input and a critical analysis of the documents provided by the companies. A search for the PPE selection methods was conducted, generating a flowchart for hearing protector selection that was implemented in a web site. Data from risk management programs of 7 Brazilian mining companies were used as input to the software once the high risk of noise exposure activities were identified. A list of adequate equipment was then generated by the software and this list was compared to the list of equipments provided by each company. After a critical analysis the software advantages were found to be the higher flexibility in the choice of hearing protectors brought by the much larger list of adequate equipment. Additional advantages include the smaller amount of time spent looking for the correct choice and the ability to provide multiple choices of equipment for workers to choose from, which increases the comfort and thus the compliance to the PPE program. The quality of the documents provided by the companies was found to be low and lacking several requirements of Brazilian Law. The created software was found to be a useful tool, further testing and improvements are needed to increase its usability and to consolidate it as an asset to health and workplace safety professionals.

Hearing protectors are used in noisy environments to attenuate damaging soundlevels. Problems are reported to arise from using hearing protectors, since usefulsounds also are attenuated. Not only are sound levels attenuated, but other humanabilities are affected by hearing protectors, such as the ability to identify and localizesounds. Manufacturers of hearing protectors also develop level-dependent hearingprotectors that are supposed to create a better listening experience for the user thandoes passive hearing protectors. This thesis investigates how the ability to identifysound is affected by hearing protectors in the Swedish processing industry and towhat extent level-dependent hearing protectors improve the user’s ability to identifysound. Semi-structured interviews were conducted by asking questions based on theprojects research questions and theories found from a literary study. A questionnairewas sent out with similar questions for verification purposes. The current literatureshows that the human ability to identify sound deteriorates by the occlusion from hearing protectors. Indications are such that hearing protectors with a level-dependent function deteriorate the ability less than does passive protectors. The relevance of this in the processing industry does not seem to be very palpable. Usersindicate that it would be dangerous for this ability to be deteriorated in theworkplace and that level-dependent hearing protectors does a better job apreserving sound identification than passive protectors, but their soundidentification ability is not deteriorated enough by passive hearing protectors forproblems to arise.

The research described herein was undertaken to determine how masked thresholds changed when individuals wore an active noise reduction (ANR) hearing protection device (HPD), a passive HPD, or no HPD. An ANR earmuff, a passive earmuff, and a user-molded foam earplug were tested in two types of noises (pink and red) at two different noise levels (85 dBA and 100 dBA). The signal used was an industry-standard backup alarm. The experimental design was completely within-subjects. An ascending method of limits was used to obtain 15-20 correct positive responses, which were then averaged to obtain the masked thresholds for each treatment condition. A visual probability monitoring task was incorporated in the experimental design to provide a loading task for the participants. In addition to masked thresholds, comfort and mental workload were assessed. Finally, participants were asked to rank each of the three HPDs with respect to their perceived ability to facilitate hearing the signal in noise. Results indicated that in 85 dBA noise, masked thresholds were lower when hearing protection devices were worn, compared to the unoccluded condition. Additionally, the results indicated that the ANR device provided a significant advantage (lower masked thresholds) over the passive earmuff in the low-frequency biased red noise (across both noise levels) and the 100 dBA noise level (across both noise spectra). However, the ANR earmuff exhibited no significant advantage over the user-molded foam earplug in any of the conditions. Rather, the user-molded foam earplug produced significantly lower masked thresholds at 100 dBA. The results also indicated that there was no difference between the three devices in their perceived ability to facilitate detection of the signal. There was also not a significant difference in comfort ratings between the three HPDs, although there were several complaints about the comfort of the ANR earmuff during the experiment. / Master of Science

Made available in DSpace on 2016-04-27T18:11:48Z (GMT). No. of bitstreams: 1 Ana Ligia Melo Martins Greca.pdf: 460056 bytes, checksum: b44d71bbbac35e1535f5b80186a51c22 (MD5) Previous issue date: 2010-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Objective. Evaluate the knowledge of workers exposed to noise in relation to hearing protection and identify prevalence and outbreaks of noiseinduced hearing loss over three years. Method. The sample consisted of 65 workers at an engineering company aged 21 to 57 years, all male and exposed to noise at or above 85 dB (A). All workers wore hearing protection. The procedures included the use of the questionnaire "Beliefs and attitudes about hearing protection and hearing loss" and analysis of audiometric tests performed in 2007, 2008 and 2009. Results: Most workers (70.8%) had a time of noise exposure in the company within one to five years. Of the total, 33 workers (50.7%) reported complaints regarding the use of hearing protectors. The most frequent complaints were itching (23.1%) and difficulty in communication (12.3%). Most workers (78.5%) reported working in noisy environment. The prevalence of noise-induced hearing loss ranged from 21.6% to 38.5% during the three years. The onset of hearing loss ranged from 23 to 38.5% in the comparison of tests from 2007 to 2009. The questionnaire answers indicated, in most cases, workers attached importance to the hearing and know the strategies of hearing protection. Conclusion: There was a statistically significant association between age and hearing loss. The questionnaire results indicated that, in general, workers have knowledge about hearing protection, despite the high prevalence rate and triggering noise-induced hearing loss / Objetivo. Avaliar o conhecimento de trabalhadores expostos a ruído em relação à proteção auditiva e identificar prevalências e desencadeamentos de perda auditiva induzida por ruído no decorrer de três anos. Método. A amostra foi composta por 65 trabalhadores de uma empresa de engenharia com idade de 21 a 57 anos, todos do sexo masculino e expostos a ruído igual ou superior a 85 dB(A). Todos os trabalhadores usavam protetores auditivos. Os procedimentos incluíram a aplicação do questionário Crenças e atitudes sobre proteção auditiva e perda auditiva e análise das audiometrias realizadas em 2007, 2008 e 2009. Resultados: A maioria dos trabalhadores (70,8%) tinha tempo de exposição a ruído na empresa no intervalo de um a cinco anos. Do total, 33 trabalhadores (50,7%) relataram queixas em relação ao uso de protetor auditivo. As queixas de maior ocorrência foram coceira (23,1%) e dificuldade de comunicação (12,3%). A maioria dos trabalhadores (78,5%) relatou trabalhar em ambiente ruidoso. A prevalência de perda auditiva induzida pelo ruído variou de 21,6% a 38,5% no decorrer dos três anos. O desencadeamento de perdas auditivas variou de 23 a 38,5% na comparação dos exames de 2007 a 2009. As respostas do questionário indicaram, em sua maioria, que os trabalhadores atribuíam importância à audição e conheciam as estratégias de proteção auditiva. Conclusão: Houve associação estatisticamente significante entre idade e perda auditiva. Os resultados do questionário indicaram que, em geral, os trabalhadores têm conhecimento com relação à proteção auditiva, apesar do elevado índice de prevalência e de desencadeamento de perdas auditivas induzidas por ruído

På bullriga arbetsplatser använder personal ofta hörselskydd med inbyggda högtalare för att lyssna på exempelvis musik i underhållningssyfte. Om användaren lyssnar på höga ljudnivåer under långa perioder kan bullerskador uppstå i dennes öron. Enligt lagstiftning måste nivån därför begränsas i förebyggande syfte. Bullernivån är ett genomsnitt av de ljudnivåer användaren exponerats för under en arbetsdag. Användaren måste vila öronen om gränsvärdet för bullernivån nås.Om man utnyttjar att det är ett genomsnitt kan användaren tillåtas lyssna på en hög ljudnivå under en begränsad tid för att sedan sänka den. Det går att bevara både säkerheten och lyssningsupplevelsen om en sänkning införs långsamt. Detta arbete beskriver hur en algoritm till en digital signalprocessor kan konstrueras för att reglera ljudnivån.Målsättningen var att algoritmen skulle skydda användarens hörsel utan att försämra lyssningsupplevelsen, och utan att förbruka mer energi än nödvändigt. I algoritmen ingick en prediktor som predikterar mängden buller användaren riskerar att utsättas för, om denne fortsätter lyssna på samma nivå.Långsamma sänkningar av ljudnivån kan då utföras i tid innan gränsvärdet nås. Det visade sig att algoritmen endast behövde ett fåtal samplingar per sekund för att skatta och reglera ljudnivån tillräckligt precist, vilket reducerade energiförbrukningen.Resultatet visar möjligheten att kombinera målen för säkerhet, lyssningsupplevelse och energieffektivitet i hörselskydd. Algoritmen implementerades inte på ett skarpt system.Den hade enbart tillgång till ljudsignalen användaren ämnade lyssna på i underhållningssyfte. / In noisy workplaces the staff are often using hearing protectors with built-in speakers for entertainment purposes. Prolonged exposure to loud sound levels can cause damage to the user’s ears. The legislation requires therefore a limiting mechanism for the speakers. The noise level is defined as the average of the sound levels the user has been exposed to during a working day. If the noise threshold is reached the user has to rest his ears. This definition can be exploited to allow the user to listen to a loud sound level for a limited time and then lowering it. If the sound level is lowered slowly, it is possible to preserve both safety and listening experience. This work describes how an algorithm can be designed for a digital signal processor with the purpose of controlling the sound level. The aim was to protect the user's hearing without spoiling the listening experience, and without consuming more power than necessary. The algorithm design included a predictor that predicts the amount of noise the user risk being subjected to, if he continues to listen at the same level. Slow reduction of the sound level can then be carried out in time before the noise threshold is reached. It turned out that the algorithm only needed a few samples per second to estimate and control the sound level sufficiently precisely, this reduced the power consumption. The results show that it is possible to combine the objectives for safety, listening experience and power consumption in hearing protectors. The algorithm was not implemented in a real system. The algorithm had only access to the audio signal which the user intended to listen to for entertainment purposes.