Manual assembly operations are sensitive to human errors that can diminish the quality of final products. The paper shows an application of human reliability analysis in a realistic manufacturing context to identify where and why manual assembly errors occur. The techniques SHERPA and HEART were used to perform the analysis of human reliability. Three critical tasks were selected for analysis based on quality records: (1) installation of three types of brackets using fasteners, (2) fixation of a data cable to the assembly structure using cushioned loop clamps and (3) installation of cap covers to protect inlets. The identified error modes with SHERPA were: 36 action errors, nine selection errors, eight information retrieval errors and six checking errors. According to HEART, the highest human error probabilities were associated with assembly parts sensitive to geometry-related errors (brackets and cushioned loop clamps). The study showed that perceptually engaging assembly instructions seem to offer the highest potential for error reduction and performance improvement. Other identified areas of action were the improvement of the inspection process and workers’ provision with better tracking and better feedback. Implementation of assembly guidance systems could potentially benefit worker’s performance and decrease assembly errors.

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This study was conducted in a warehouse at a vaccine production centre where improvement to existing storage and working conditions were sought through the construction of a new refrigerated store section (2-8C°). Warehousing tasks were videotaped and ergonomics analysis tools were used to assess the risk of developing MSDs. Specifically, these tools were the Rapid Entire Body Assessment (REBA) and the NIOSH equation. The current plant layout was sketched and analyzed to find possible targets for improvement trough the application of general work space design and ergonomics principles. Seven of the eight postures evaluated with REBA had a total score between 8 and 10, meaning a high risk, and only one was at a medium risk level. Nine of the eleven manual material handling tasks analyzed with the NIOSH equation had a Lifting Index between 1.14 and 1.80 and two had a recommended weight limit of 0kg, indicating a need for job redesign. Solutions included the redesign of shelves, the design of a two-step stair and a trolley with adjustable height; also, changes in work methods were proposed by introducing a two-workers lifting strategy and job rotation, and, finally, a restructuring of plant layout was completed.

BACKGROUND: Fatigue and workload experienced by aircraft de-icing personnel have been largely neglected in occupational health and safety research. OBJECTIVE: To provide an initial assessment of fatigue and workload among de-icing ground crews. METHODS: Company records were used to reveal possible relationships between different variables (age, seniority, truck type, and work shift). A group of 20 volunteer participants (17 men and 3 women) rated their level of fatigue before and after one shift using the Samn-Perelli fatigue scale. Workload was evaluated using the NASA-TLX method at the end of the shift. RESULTS: The average fatigue experienced by de-icing worker was significantly greater (P = 0.043) for the technicians in open-basket trucks than for the ones in trucks with a cabin (4.43 vs 3.37). Furthermore, there was a significant age difference (P = 0.048) in the perceived level of fatigue (4.1 vs 3.1), with younger workers (< 30 years) reporting a higher level than older workers (30 years). Overall NASA-TLX score were not significant (P > 0.05) for any of the factors tested: type of truck, shift and age. CONCLUSIONS: The results suggest that particular attention should be paid to young technicians and technicians working in open-basket trucks, since the fatigue levels reported in association with these factors were higher.

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La ergonomía es considerada, en la actualidad, una disciplina científica consolidada, que se expande continuamente a nivel global. Este escenario actual es el resultado de diferentes visiones que han permeado la evolución de la ergonomía. En este artículo se hace un recorrido histórico de la ergonomía como disciplina, tomando en cuenta la escuela de los factores humanos y la escuela de la ergonomía de la actividad. Se presentan los orígenes de estas escuelas, sus paradigmas subyacentes y se realiza una comparación entre ellas. Las reflexiones presentadas en el artículo en torno a la ergonomía parten de la idea que, desde las diferencias y la diversidad, se erige el desarrollo. Los autores de este artículo son partidarios de abordar la ergonomía como una única disciplina, reconociendo la convergencia y la complementariedad entre las dos escuelas. Más allá de las diferencias existentes, la práctica de la ergonomía debe enfocarse en el diseño de los sistemas de trabajo, tomando como eje central al ser humano. Se espera que estas reflexiones permitan a los profesionales de la ergonomía y de otras diciplinas afines ganar mayor comprensión de cómo abordar la actividad humana para transformarla positivamente.

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Los errores de medicación representan un problema de salud pública que afecta la seguridad del paciente y la calidad de los servicios de salud a escala global. En este artículo se presenta un procedimiento para el análisis y la prevención de los errores de medicación desde la perspectiva de la ergonomía, ejemplificándose su aplicación mediante un caso de estudio ilustrativo de administración de un medicamento inyectable. Como parte del procedimiento expuesto, se incluyeron los reconocidos métodos Hierarchical Task Analysis (hta) para el análisis de la tarea y Systematic Human Error Reduction and Prediction Approach (sherpa) para la identificación de los modos de error. Para la valoración de riegos se propone una matriz de riesgos cualitativa. El procedimiento propuesto quedó conformado por cuatro etapas: 1) selección de la tarea objeto de estudio, 2) análisis detallado de la tarea, 3) predicción de la posibilidad de error y 4) desarrollo de estrategias para la reducción del error. Se espera que la utilización sistemática de este procedimiento contribuya en la mejora de la calidad de los servicios de salud, disminuyendo los errores humanos y los posibles eventos adversos.