Evaluación de la carga fisiológica de trabajo con fines ergonómicos en actividades mineras que se desarrollan en altura geográfica / Evaluation of physiological workload for ergonomic purposes in mining activities performed in geographical altitude

Desde la perspectiva de la Ergonomía y la Fisiología del Trabajo, hay escaso conocimiento acerca del impacto que trabajos de alta demanda energética, efectuados en altura geográfica, tienen sobre el bienestar laboral de quienes los ejecutan. La evaluación de la respuesta fisiológica durante trabajos reales en altura no es simple. Las dos variables más utilizadas para cuantificar la intensidad de los esfuerzos son el consumo de oxígeno (VO2) y la frecuencia cardíaca (fC). La primera técnica es compleja, mientras que la segunda permite seguimientos de jornadas completas sin alterar el trabajo. Además, cuando se asocia a las actividades que la persona realiza, permite identificar cargas peak y proponer soluciones para evitarlas o reducirlas. En consecuencia, el objetivo del presente estudio es analizar y proponer una metodología simple, de bajo costo, para la evaluación de la carga fisiológica, combinando estudios de tiempo y medición de frecuencia cardíaca, en trabajadores que se desempeñan en altura geográfica. En cuanto a métodos, el estudio se efectuó en 23 trabajadores que tenían entre 26 y 60 años de edad. A cada uno de ellos se le hizo un seguimiento de jornada con registros continuos y sincronizados de tiempo y fC. Los principales resultados revelaron una correlación inversamente proporcional entre edad y frecuencia cardíaca peak. Al mismo tiempo, la metodología propuesta se demostró muy útil para identificar cargas de altas demandas fisiológicas, como apoyo para la búsqueda de soluciones ergonómicas. En síntesis, se concluye que la metodología propuesta, asociada a un enfoque de ergonomía participativa, permite abordar las tareas más críticas, identificar la intensidad de los esfuerzos y proponer soluciones en los casos de mayor sobrecarga.

From the perspective of Ergonomics and Work Physiology, there is little knowledge about the impact of high energy demand, performed in geographic altitude, over the well-being of their workers. The assessment of the physiological answer during real works in altitude is not a simple task. The two more used variables to quantify the intensity of the efforts are the oxygen intake (VO2) and cardiac frequency (fC). The first technic is complex, while the second allows a follow-up of the complete workdays without disturbing the work. Furthermore, when activities are associated with the person that performs it, it allows us to identify charges peak and propose answers to avoid and reduce them. As result, the aim of the present study is to analyze and propose a simple methodology, of low cost, to assess the physiological load, combining time studies and measurement of cardiac frequency, in workers performing in geographic altitudes. As for methods, the study was performed in 23 workers from 26 to 60 years old. A workday follow-up was performed to each of the workers with continuous and time-synchronized registers and fC. The main results displayed an inversely proportional link between age and peak cardiac frequency. At the same time, the proposed methodology proved to be useful to identify loads of high physiological demands, like support for the seek of ergonomic solutions. In summary, we concluded that the proposed methodology, associated with a collaborative ergonomic approach, allowing us to address the most critical tasks, identify the intensity of the efforts, and propose solutions in the cases of greater overload.

Fascitis plantar. Criterios y experiencias sobre la infiltración con anestésicos locales y corticoesteroides / Plantar fasciitis Criteria and experiences on infiltration with local anesthetics and corticosteroids

Introducción: Dentro del grupo de las enfermedades del sistema osteomioarticular la fascitis plantar (FP) es una de las causas más frecuente de dolor crónico del pie. Objetivo: aportar criterios sobre el empleo de la infiltración de anestésicos locales y corticoesteroides para el tratamiento de la fascitis plantar. Desarrollo: se seleccionaron las infiltraciones de corticoesteroides y de anestésicos locales que se realizan con mayor frecuencia en la práctica clínica, se analizó su efectividad según la evidencia en la literatura internacional y a partir de ahí se contrastaron los resultados encontrados con los criterios y experiencias de los autores de este trabajo. Conclusiones: Las consideraciones realizadas en este estudio apuntan a que el uso de los corticoides mediante infiltraciones en patologías ortopédicas es un medio valioso para mejorar la inflamación de los tejidos y para el alivio de los dolores, tanto cuando se emplea en las articulaciones como en las partes blandas(AU)

Introduction: within the group of diseases of the osteomioarticular system, plantar fasciitis (FP) is one of the most frequent causes of chronic foot pain. Objective: to provide criteria on the use of infiltration of local anesthetics and corticosteroids for the treatment of plantar fasciitis. Development: the infiltrations of corticosteroids and local anesthetics that are performed more frequently in clinical practice were selected, their effectiveness was analyzed according to the evidence in the international literature and from there the results were contrasted with the criteria and experiences of the patients authors of this work. Conclusions: the considerations made in this study suggest that the use of corticosteroids through infiltrations in orthopedic pathologies is a valuable means to improve inflammation of the tissues and for the relief of pain, both when used in the joints and in the joints and soft parts(AU)

On the road toward the development of clothing size standards and safety devices for Chilean workers.

The range of sizes used in Chile for clothing comes from criteria developed in continental Europe, mainly the EN 13402 standard. Any standard adopted by a country should consider the anthropometric dimensions of the user population, particularly to discern the ratio of garments for different size. Consequently, the purpose of this study was to propose standards for the size of clothing based on anthropometric characteristics of a sample of Chilean miners. The study was conducted in 447 male workers. The age and body weight were measured in each workers as well as their percentage of body fat. Anthropometric measurements for garments were made according to the criteria of the European Community (EN 13402-1) and ISO (8559- 1989). Body dimensions for the design of gloves, shoes, helmets and caps, clothes that cover the upper part of the body and clothes that cover the lower part were measured. The results obtained made it possible to establish the percentage of workers falling within the range of sizes that manufacturers consider as reference. One of the main conclusions of the study is the need to carefully consider a set of complementary anthropometric measures, which can help to improve the comfort of costumes, to the extent that the providers adapt their designs to the characteristics of Chilean workers.

Ergonomic study of an operator's work of a molybdenum plant.

This study was part of an ergonomic program which is being carried out through an agreement between the University of Concepción and a Chilean private mining company. The purpose of this case study was to identify working conditions in which the physical and mental workload could be over the capabilities of the operator. He was responsible for loading trucks with sacks of molybdenum and for downloading reagents and handles them. The methods employed in this study included electronic records, interviews, surveys, review of the company standards, a time study and physical and mental workload analysis. Results showed that 84% of the time the operator was carrying out principal and secondary activities and no break periods were detected. It was found that the pace of work and the shift system generated unfavorable conditions by imbalance in the workload on the different days of the week. In the light of the results recommendations were made for a number of ergonomic changes. Most of them were accepted by the company. The most important achievement was a change in the shift system. The overload of the operator was due to the fact that he was in a shift working 5 days and resting on weekends. The imbalance was mainly because the work of the week end was accumulated for Monday. As a result of the study, the company contracted a second worker for this job and adopted a 7x7 shift system, meaning that they work seven days and rest seven days. An evaluation carried out two month after adopting the new shift revealed that changes were well accepted by the worker.