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Made available in DSpace on 2016-06-02T19:50:21Z (GMT). No. of bitstreams: 1 DissFFC.pdf: 1785587 bytes, checksum: ed00627d6a4426236fccbdd1227c71eb (MD5) Previous issue date: 2004-12-14 / Financiadora de Estudos e Projetos / The recent changes in the work s world have modified and amplified the performance field of the ergonomics. Through a brief methodological discussion about the Ergonomic Work Analysis and a bibliographical revision about undertaken ergonomic interventions, it was verified that the results of work transformation through Ergonomic Work Analysis not always will be positive. Consequently, this work had an objective of analyzing an ergonomic intervention accomplished in a powdered detergent company, due to understand how ergonomic actions are incorporated for the different social actors and how the company, through the management, could appropriate of the results in behalf of the production. The process of activity transformation of the Vincador, from the initial demand for recommendations implemetation and validation, as well as the established social relationships and the Vincadores roles, managers, Internal Committee of Ergonomics and the company were analyzed under the Ergonomic Work Analysis point of view. The results showed that Vincadores work rhythm has increased after the ergonomic recommendations implemetation as a consequence of management s appropriation of regulations margins, whose intention was to increase the process effectiveness without considering the balance between health versus productivity. The non-incorporation of the activity point of view helped, therefore, that changes of interests, values and the involved actors logic s, lead to commitment break, before firmed among those, turning the new situation noxious for the Vincadores health. / As recentes alterações no mundo do trabalho modificaram e ampliaram o campo de atuação da ergonomia. Através de uma breve discussão metodológica sobre a Análise Ergonômica do Trabalho (AET) e uma revisão bibliográfica sobre intervenções ergonômicas empreendidas, pôde-se constatar que os resultados da transformação do trabalho pela AET nem sempre serão positivos. Diante deste cenário, este trabalho teve como objetivo analisar uma intervenção ergonômica realizada em uma empresa de detergente em pó, para compreender como as ações ergonômicas são incorporadas pelos diferentes atores sociais e como a empresa, através da gerência, pode se apropriar dos resultados obtidos em benefício apenas da produção. O processo de transformação da atividade do Vincador, desde a demanda inicial até a implementação e validação das recomendações, assim como as relações sociais estabelecidas e o papel dos Vincadores, dos gerentes, do Comitê Interno de Ergonomia e da empresa foram analisados sob o ponto de vista da AET. Os resultados mostraram que após a implementação das recomendações ergonômicas, ocorreu a intensificação do ritmo de trabalho dos Vincadores como conseqüência da apropriação das margens de regulação pela gerência, que visava a maior eficácia do processo sem considerar o equilíbrio saúde versus produtividade. A não incorporação do ponto de vista da atividade possibilitou, portanto, que as mudanças de interesses, valores e lógicas dos atores envolvidos, levassem a quebra do compromisso que havia sido firmado entre esses, tornando a nova situação, nociva à saúde dos Vincadores.

Cette thèse s’inscrit dans le champ de recherche en ergonomie qui porte sur les acteurs de la prévention. Elle défend l’idée que l’activité des représentants du personnel est un travail et qu’il est possible de contribuer au développement de leur activité à travers des interventions ergonomiques.Elle a été conduite auprès de sept CHSCT de métiers différents de la SNCF et fait suite à une demande sociale formulée par l’Observatoire de la Qualité de Vie au Travail de cette entreprise. Les membres de cet Observatoire souhaitaient avoir un éclairage scientifique pour comprendre les difficultés de fonctionnement de ces instances et les possibilités d’y améliorer la prise en compte du travail pour contribuer à la prévention de la pénibilité.Par l’Analyse Ergonomique du Travail, il a été possible de comprendre les spécificités de cette activité. Plusieurs interventions ergonomiques ont été mises en place au sein de sept CHSCT pour mettre à l’épreuve les diagnostics locaux réalisés. Il a ainsi été possible de contribuer au développement de l’activité des représentants du personnel.Cette thèse démontre que les représentants du personnel sont des praticiens qui contribuent par leur activité à résoudre les problèmes de l’entreprise. Pour autant, le cadre réglementaire ne leur permet pas de prendre en charge le caractère dynamique des situations de travail des salariés et les possibilités d’action de leur propre activité. Cela les amène à définir des modes d’action qui soient en adéquation avec l’environnement dynamique dans lequel ils agissent.Il leur est de fait nécessaire de construire un référentiel commun permettant d’articuler une nécessité d’agir ensemble tout en tenant des points de vue individuels. La conflictualité et la coopération sont par conséquent inhérentes au mode de fonctionnement des CHSCT. Toutefois, ce cadre commun doit s’appuyer sur d’autres éléments que la réglementation et il est nécessaire de donner une place aux salariés dans la construction des problèmes et des solutions.Il apparaît également qu’il est difficile pour eux de pouvoir débattre des difficultés individuelles et collectives qu’ils rencontrent. Cela contribue au développement de défenses collectives amenant à un traitement des problèmes en vase clos au sein de l’instance.Dès lors, l’intervention ergonomique doit faciliter une activité collective par la mise en débat des pratiques et des difficultés individuelles et collectives. Toute la difficulté pour l’intervenant étant qu’il ne s’appuie pas sur un collectif de travail qui pour autant doit développer un travail collectif. Il s’agit ainsi de contribuer à ce que le dénominateur commun entre les membres permette d’y intégrer la complexité du travail et les salariés. En cela, la conflictualité et la coopération doivent s’articuler autour des situations de travail des salariés et non uniquement de l’application de la réglementation. / This dissertation falls within a field of research in ergonomics focused on health and safety staff. It defends the idea that the activity of staff representatives is to be considered as work and that it is possible to contribute to the development of their activity thanks to ergonomic interventions.This research was carried out by studying seven CHSCTs (Occupational Health and Safety Committee) of different professions at the SNCF (French National Rail Company), and was ordered by their Observatoire de la Qualité de Vie au Travail (Monitoring Agency for Quality of Life in the Workplace). The members of the Observatoire wanted a scientific study to help them understand the functional difficulties encountered by the CHSCTs, and the possibilities for improving work analysis, in turn improving their prevention work.Thanks to an Ergonomic Work Analysis, we were able to understand the specificities of this activity. Several ergonomic interventions were organized in order to test previous local diagnostics. We were thus able to contribute to the development of the activity of staff representatives.This dissertation shows that staff representatives are practicians who, through their activity, contribute to problem solving in the company. The current regulations framework does not permit them to take into account the dynamic nature of employees' work situations, nor the possibilities for action in their own work. This has lead them to defining modes of action that are in line with the dynamic environment in which they are called upon to intervene.It is therefore necessary for them to build a common frame of reference in order to act together, while still retaining individual points of view. Inevitably, conflictuality and cooperation are inherent to the functioning of CHSCTs. This common framework however must be based upon other elements besides regulations, and it is necessary to give employees a say in the formation of both problems and solutions.It also appears to be difficult for them to discuss the individual and collective difficulties that they encounter. This contributes to the development of collective defenses, leading to a closed, in-house treatment of the workers situational problems.As such, ergonomic interventions must facilitate collective activity by questioning both individual and collective pratices and difficulties. The challenge for the ergonomist is that he cannot base his intervention upon a work collective, which must none-the-less produce a collective work. Therefore the contribution must work towards a common denominator between the members, allowing for the integration of both the complexity of work and the employees. In that, conflictuality and cooperation must be articulated around employees' work situations, and not only the application of regulations.

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Occupational upper extremity disorders have become a major issue in modern society. Poorly designed workplaces, high job demands, and incorrect work-habits can lead to the development of upper extremity disorders (UEDs) in the workplace. This issue not only causes health-relatedproblems for the individual but also forms a significant economic burden on society due to sickleaves, healthcare and untimely exit of affected individuals from the workforce. The risk of developing occupational UEDs varies with different professions. The European Agency for Safety and Health at Work (EU-OSHA) has recognized significant occupational health risks associated with the hairdressing profession. It has been estimated that UEDs are five times more prevalent amongst hairdressers than other professions. Qualitative risk assessment tools based on self-reports and observation have been used to identify the risks of developing UEDs with hairdressing profession before. However, a quantitative risk assessment tool that provides objective data on work posture is more precise and objective than self-report and observation. This data can help to identify the risks of developing UEDs associated with each hairdressing task. Furthermore, it can enable self-assessment of workload and posture awareness by providing feedback to the user. Inertial Measurement Units (IMU) as part of a wearable system developed at KTH were used in this study to investigate the risks of developing UEDs for hairdressing students. The feasibility of using a feedback function for providing posture awareness was also evaluated by comparing the measurements obtained with and without using the feedback function. Twelve hairdresser students were enrolled in the study. The percentage of time for elevated angles above 30°, 60° and 90° for arms, and above 45° or less than 0° for the trunk flexion is presented. In addition, 10th and 90th percentiles (°) of arms and trunk angular distribution is presented. The result of a statistical analysis performed on data with and without feedback was used to evaluate the effectivity of using the feedback function in preventing the development of occupational UEDs. A System Usability Scale (SUS) questionnaire was used to evaluate the overall usability of the system. The result of this study confirms that the hairdressing profession falls in the high-risk category for developing UEDs. The use of this technical system has enabled a precise risk assessment evaluation of each hairdressing task. Such data can be used as a foundation for improving the ergonomic design of the workplace. The feasibility of using the feedback function as a prevention tool on the individual level is highly dependent on the individuals’ motivation and their attitude towards changing their work habits. However, the results in general, indicate a decrease in the abduction angle (°) for both left and right arm when the feedback function is used. For example, the 90th percentile abduction angles (°) for left arm (all 12 subjects) during the drying part of one fundamental work-cycle decreased from a value of 60.4° to 58.2° when the feedback function was used. The 90th percentile abduction angles (°) for the right arm during the same part of the fundamental work-cycle decreased from an angle of 53.1° to 51.4°. The SUS score of 75.6 indicates good overall usability for the system. / Besvär i det muskuloskeletala systemet i överkroppen som uppkommer på grund av påfrestande arbetsställningar och icke-optimala arbetsvanor blir allt vanligare i det moderna samhället. Besvären orsakar inte bara hälsorelaterade problem för individen utan även en avsevärd ekonomisk börda för samhället. Risken för att utveckla skador i överkroppen varierar med olika yrken. Europeiska arbetsmiljöbyrån (EU-OSHA) har identifierat betydande hälsorisker i samband med frisörarbete. Det har uppskattats att besvär i överkroppen är 5 gånger mer förekommande hos frisörer jämfört med andra yrken. Det finns många forskningsprojekt som har använt kvalitativa riskbedömningsverktyg, baserade på självrapportering och observation, som identifierar riskerna med att utveckla skador i överkroppen bland frisörer. Ett kvantitativt riskbedömningsverktyg som ger objektiva data om arbetsställning är dock mer exakt än självrapportering och observation. Ett sådant verktyg kan hjälpa till att identifiera risken för skadeutveckling i överkroppen. Inertial Measurement Units (IMUs) är en del av ett bärbart mätsystem som har utvecklats påKTH. Systemet användes i denna studie för att identifiera risken för skadeutveckling i överkroppen bland frisörer. Riskidentifieringen gjordes genom att mäta vinkel på armar och rygg. Mätsystemet har även en inbyggd återkopplingsfunktion som uppmärksammar användaren om deras kroppsställning. Effektiviteten av att använda återkopplingsfunktionen för att förebygga jobbrelaterade skador utvärderades genom jämförelse av mätningar som erhållits med och utan återkopplingsfunktion. Tolv frisörstudenter deltog i studien. Överkroppspositionen definierades av vinklar över 45° eller mindre än 0° från en position där ryggen är rak. Abduktionsvinklar över 30°, 60° och 90° mättes för armar. Tidsperioden för dessa vinklar d.v.s. hur lång tid överkroppen hölls i dessa vinklar räknades. Armar och överkroppvinklar för 10:e och 90:e percentilen (°) samt resultat av en statistisk analys som utfördes på data samlade med och utan återkopplingsfunktionen presenterades. Analysen utfördes för att utvärdera hur effektiv återkopplingsfunktionen är för att förhindra arbetsskadeutveckling. En System Usability Scale (SUS) frågeformulär användes för att utvärdera systemets övergripande användbarhet.Resultatet av denna studie bekräftar att frisöryrket faller i högriskkategorin för arbetsskadeutveckling. Användningen av detta bärbara mätsystem har möjliggjort en exakt riskbedömning för olika arbetsuppgifter. En sådan information kan användas som grund för att förbättra ergonomiska förhållanden på arbetsplatser. Effektiviteten av återkopplingsfunktionen som ett förebyggande verktyg på individnivå är starkt beroende av individernas motivation och deras inställning till att ändra sina arbetsvanor. Emellertid anger resultaten en generell minskning av armvinklar (°) för både vänster och höger arm när återkopplingsfunktionen används. Till exempel har den 90:e percentil vinklarna (°) för vänsterarm (alla 12 personer) under hög belastning minskat från ett värde av 60.4° till 58.2 °. Den 90:e percentil vinklarna (°)för höger arm under hög belastning har också minskat från ett värde av 53.1° till 51.4°. SUS-poängen på 75.6 indikerar en bra användbarhet för systemet

Low back pain (LBP) remains the most prevalent and costly work-related disability worldwide and is directly associated with "physical" risk factors prevalent in manual material handling (MMH) tasks. Back-support exoskeletons (BSEs) are a promising ergonomic intervention to mitigate LBP risk, by reducing muscular exertion and spine loading. The purpose of this work was to help better understand both the "intended" and "unintended" consequences of BSE use on physical risk factors for LBP, as an essential prerequisite for the safe and effective implementation of this technology in actual workplaces. The first study assessed the effects of using two BSEs on objective and subjective responses during repetitive lifting involving symmetric and asymmetric postures. Wearing both BSEs significantly reduced peak levels of trunk extensor muscle activity and reduced energy expenditure. Such reductions, though, were more pronounced in the symmetric conditions and differed between the two BSEs tested. The second study quantified the assistive torque profiles of two passive BSEs using a computerized dynamometer, with both human subjects and a mannequin. Clear differences in torque magnitudes were evident between the BSEs, though both generated more assistive torques during flexion than extension. The third study estimated the effects of BSE use on lumbosacral compressive and shear forces during repetitive lifting using an optimization-based model. Using both BSEs reduced peak compression and anteroposterior shear forces, but these effects differed between tasks and BSE designs. Reductions in composite measures of trunk muscle activity did not correspond consistently with changes in spine forces when using a BSE. The fourth study quantified the effects of two passive BSEs on trunk stability and movement coordination during repetitive lifting. Some adverse effects on stability were evident for pelvis and thorax movements and coupling of these body segments, suggesting that caution is needed in selecting a BSE for a given MMH task. Overall, we found that the efficacy of BSEs is design- and task-specific. Important safety features of the exoskeletons were also identified, providing insights on their performance boundaries. Overall, the BSEs tested were more effective and safer in tasks closer to the mid-sagittal plane and with moderate degrees of trunk flexion. / Doctor of Philosophy / Low back pain (LBP) remains the most prevalent and costly work-related disability worldwide, and the risk of LBP is related to "physical" risk factors common in manual material handling (MMH) tasks. Back-support exoskeletons (BSEs) are a new ergonomic intervention that may reduce the risk of occupational LBP, by reducing muscular efforts and loads on the spine. For the safe use of BSEs, though, it is critical to better understand both the "intended" and "unintended" consequences of this emerging technology. In this dissertation, such consequences of BSE use were evaluated in the context of repetitive lifting tasks. The first study assessed the efficacy of two BSEs in terms of physical demands during repetitive lifting tasks involving a range of torso bending and twisting. Wearing both BSEs reduced the physical demands on back muscles and decreased energy consumption. Larger reductions, though, were observed in forward bending and such reductions differed between the two BSEs tested. The second study measured the amount of support provided by two BSEs using a new measurement method, which was examined for both human subjects and a mannequin. Clear differences in the BSE support were evident between the BSEs, and both devices generated more support during torso forward bending than returning upright. The third study estimated the effects of BSE use on low back loadings during repetitive lifting using a computational model. Using both BSEs reduced loads on the low back region, though such reductions were task-specific and depended on the BSE design. The fourth study quantified the effects of the BSE use on torso stability and movement patterns during repetitive lifting. Some adverse effects on stability were evident for lower and upper torso, suggesting that caution is needed in selecting a BSE for a given MMH task. Findings from this work show the potential benefits of BSEs for use in MMH tasks, yet such benefits can depend on the BSE design and the MMH task they are used for. Further, BSE use can lead to adverse effects, especially with tasks involving extreme working postures.

Made available in DSpace on 2016-06-02T19:51:27Z (GMT). No. of bitstreams: 1 DissLFM.pdf: 513655 bytes, checksum: 950c918317e43b508645211bba44287b (MD5) Previous issue date: 2003-01-01 / Ergonomics changes in the work place interfere in the relation between over operators work and health. This case study had as its objective to analyze the repercussions of a process of changes technical and organizational due to ergonomic projects in a school material plant. Two company sectors were selected which are responsible for the main product external completion. One of the sectors received the full ergonomic intervention and the other had only little adjustments. In order to develop this study, the following procedures were executed: questionnaire applications, observations in order to understand the work activity in both sectors and interviews with the objective of comprehending different actors perception of changes in the in the company. The results indicated that, after the ergonomic intervention, there was a reduction in absenteeism due to RSI/WRMD, changes in physical and cognitive task requests, a differentiated interpretation of results for each social group in the company and na appropriation, by the company, of the results and transformation process started by the ergonomic project for other purposes. This case study revealed the importance of the evaluation process of an ergonomic intervention, because it confirms that a positive result in relation to the demand that originated the intervention, will not always grant future improvements. The analyzed situation points to new problems, whose repercussions are not yet known, but need to be discussed. / As modificações ergonômicas no ambiente de trabalho interferem na relação entre saúde e trabalho. Este estudo de caso teve como objetivo analisar as repercussões do processo de mudanças técnicas e organizacionais decorrentes dos projetos de ergonomia de uma empresa do setor de material escolar sobre o trabalho e a saúde dos operadores. Foram selecionados dois setores responsáveis pela etapa de acabamento externo do principal produto da empresa. Um setor recebeu a intervenção ergonômica e o outro sofreu pequenas modificações. Para o desenvolvimento deste estudo foram realizados os seguintes procedimentos: aplicação de questionários, observações para compreender a atividade de trabalho nos dois setores e entrevistas para percepção das mudanças nos diferentes atores da empresa. Os resultados apontaram que após a intervenção ergonômica houve diminuição dos afastamentos por LER/DORT, modificações nas exigências físicas e cognitivas das tarefas, uma interpretação dos resultados da intervenção diferenciada para cada grupo social da empresa e apropriação pela empresa dos resultados e do processo de transformação do projeto de ergonomia para outros fins. O estudo deste caso revelou a importância do processo de avaliação de uma intervenção ergonômica, porque confirma que um resultado positivo em relação à demanda da intervenção nem sempre irá garantir condições de trabalho satisfatórias. A situação estudada aponta novos problemas cujas repercussões ainda são desconhecidas, mas que necessitam ser discutidas.

Ce travail de recherche a pour objectif de proposer une lecture de l’intervention ergonomique et des modèles sous‐jacents à la pratique, à partir de la compréhension des spécificités du travail collectif des ergonomes consultants.Pour instruire cette question de recherche, nous avons identifié les caractéristiques du travail collectif, puis considérant l’ergonome consultant comme un opérateur, nous avons cherché à caractériser les spécificités du travail collectif. Pour cela, nous avons étudié les modèles d’intervention sous‐jacents à la pratique et nous avons recherché les modalités d’instanciations nécessaires aux particularités du travail des consultants energonomie.La problématique traitée est issue d’une construction progressive entre la pratique et la recherche. La méthodologie originale, développée dans ce travail, reflète cette construction. Cette démarche et les données rassemblées permettent ainsi de montrer que la compréhension de l’activité de travail des consultants doit passer par une analyse préalable de leurs déterminants professionnels. Celle‐ci permet de comprendre les modalités d’instanciation des macros modèles souples d’intervention, nécessaires à la gestion des variabilités des demandes traitées et des contextes d’interventions. Cette compréhension du travail des ergonomes permet d’appréhender pourquoi les ergonomes ne font pas tous la même chose et quelles sont les conditions favorables au travail collectif dans l’intervention ergonomique. / The aim of this research is to propose a reading of ergonomics intervention and of models underlying practice of ergonomics, on the basis of the understanding of the specificities of consultants ergonomists collective work.To address this research question, we identified characteristics of collective work, then considering the consultants ergonomists as an operator, we aim at characterising specificities of collective work. In this sense,we studied intervention models underlying practice and we searched for instantiations of these models that are required for the work of consultants ergonomists.Our research question has been elaborated through a progressive construction between research and practice.The novel methodology developed in this work reflects this construction. This approach and our collected data highlight that the understanding of consultants ergonomists activity comes through a preliminary analysis oftheir professionals determinants. This analysis helps in understanding instantiations of flexible intervention macro‐models, which are necessary to cope with variability of proposals and contexts of interventions. This understanding of the work of ergonomists helps in apprehending the reason why ergonomists have various actions and the favourable conditions for collective work during ergonomics interventions.