Digital asthenopia: blue-blocking lenses and + 0,40D additional power in the near zone, for eye strain, accommodation and convergence functions / Astenopia digital: avaliação de lentes com filtro de luz azul e poder adicional de +0,40D na zona de perto, para fadiga visual e nas funções de convergência e acomodação

ABSTRACT Purpose Evaluate blue-violet light filter and additional power of +0.40 D in the near zone ophthalmic lenses, on convergence, accommodative functions, and symptoms of digital asthenopia (DA). Methods Randomized study in cross-over design conducted on 49 volunteers (age, 29 ± 5.5 years; male: female, 18:31). Each subject wore test (+0.40 D in the near zone) and control lenses (regular single vision) for 4 weeks in randomized order. Both lenses had a selective blue-violet light filter. A baseline measurement was taken with the subjects' current updated glasses. Accommodation amplitude (AA) and near point of convergence (NPC) were measured binocularly with the RAF ruler. DA was evaluated by a questionnaire. Results No significant difference (p=.52) was found for AA comparing baseline (11.50±1.88 D), test (11.61± 1.62 D), and control SV lenses (11.88±1.50 D). No significant difference was found for NPC (p=.94), between baseline (6.50 ± 2.89cm), test (6.71± 3.49) and control SV lenses (6.82± 3.50 cm). No significant difference was found comparing test and control SV lenses in symptoms of DA (p=0.20). Conclusions The +0.40 D lenses have no negative impact on convergence or loss of accommodation power. The +0.40 D and control SV lenses had a similar impact on attenuating symptoms of DA.

RESUMO Objetivo Avaliar os efeitos do uso de lentes oftálmicas com filtro seletivo de luz azul-violeta, sem e com poder adicional de + 0,4D na zona de perto nas funções de acomodação e convergência e para sintomas de astenopia digital (AD). Métodos Ensaio clínico controlado, randomizado e mascarado, com 49 voluntários (idade, 29 ± 5,5 anos; masculino: feminino, 18: 31). Cada participante usou lentes de teste (+0,40 D na zona de perto) e controle (visão simples), por 4 semanas de forma randomizada. Ambas as lentes tinham filtro seletivo de luz azul-violeta. A medição inicial (baseline) foi feita com os óculos atualizados de cada participante. A amplitude de acomodação (AA) e o ponto de convergência próximo (PPC) foram medidos binocularmente com a régua RAF. A AD foi avaliada por um questionário. Resultados Não houve diferença estatisticamente significante (p=0,52) para as medidas de AA comparando as lentes baseline (11,50±1,88 D), teste (11,61±1,62 D) e controle VS (11,88±1,50 D). Nenhuma diferença significativa foi encontrada para a medida do PPC (p=0,94), entre as lentes baseline (6,50 ± 2,89cm), teste (6,71±3,49) e controle VS (6,82±3,50 cm). Nenhuma diferença significativa foi encontrada comparando lentes teste de VS e controle nos sintomas de AD (p=0,20). Conclusões As lentes com +0,40 D não têm impacto negativo na convergência ou na perda de acomodação. As lentes +0,40 D e controle VS, tiveram impacto semelhante na redução dos sintomas de AD.

Mudança de fotoperíodo: proposta de modelo experimental / Change of photoperiod: proposal for an experimental model

Introduction: There are some physiological and behavioral variations related to seasonality, and light is the major synchronizer of these variations according to the seasonal functions in temperate latitudes. Thus, the objective of this study was to validate a methodology for photoperiod modification in Wistar rats byevaluating its interference in the biological rhythm. Methods: Three male adult Wistar rats (60 days) were exposed to 3 photoperiods of 17 days each, with different light/dark cycles (LD): LDPP/SDPP Animal, exposed to initial LD 16:30/07:30 (LDPP, long-day photoperiod) and final LD 07:30/16:30 (SDPP, short-day photoperiod); SDPP/LDPP Animal, exposed to initial LD 07:30/16:30 and final LD 16:30/07:30; and final LD 16:30/07:30; and CT Animal, under constant LD 12:00/12:00. LDPP/SDPP and SDPP/LDPP animals underwent an intermediate photoperiod between initial and final LD, in which light exposure was increased or reduced by 30 min each day until the photoperiods were inverted. All animals remained isolated during the study and had their core temperatures continuously measured by sensors implanted in the peritoneal cavity and their locomotive activity assessed by sensors attached to their cages. The data obtained were used to construct histograms. Results: LDPP/SDPP and SDPP/LDPP animals had a longer period of activity in the SDPP than in the LDPP. The temperature of the CT animal followed a rhythmic pattern. The rat strain used was sensitive to changes in photoperiod. Conclusions: The model proposed and validated in this study can be used in experiments that aim to assess the consequences of changes in light exposure.

Introdução: Existem variações fisiológicas e comportamentais relacionadas à sazonalidade, e a luz é o principal sincronizador destas variações de acordo com as funções sazonais em latitudes de climas temperados. Sendo assim, o objetivo deste estudo foi validar uma metodologia de modificação de fotoperíodo com ratos Wistar avaliando sua interferência no ritmo biológico. Métodos: Três ratos Wistar machos adultos (60 dias) foram expostos a 3 fotoperíodos de 17 dias cada, com diferentes ciclos claro/escuro (light/dark, LD): Animal CL/CC, exposto a LD inicial 16:30/07:30 (CL, claro longo) e LD final 07:30/16:30 (CC, claro curto); Animal CC/CL, exposto a LD inicial 07:30/16:30 e LD final 16:30/07:30; e Animal CT, sob LD constante 12:00/12:00. Os animais CL/CC e CC/CL passaram por um fotoperíodo intermediário entre o LD inicial e final, no qual a exposição à luz foi aumentada ou diminuída em 30 min a cada dia até que os fotoperíodos se invertessem. Todos os animais permaneceram isolados durante o estudo e tiveram suas temperaturas corporais continuamente aferidas por sensores implantados na cavidade peritoneal e suas atividades locomotoras medidas por sensores acoplados às suas caixas. Os dados obtidos foram utilizados para construção de histogramas. Resultados: Os animais CL/CC e CC/CL apresentaram maior período de atividade em CC do que em CL. A temperatura do animal CT seguiu um padrão rítmico. A linhagem utilizada apresentou sensibilidade à mudança de fotoperíodo. Conclusão: O modelo proposto e validado neste estudo pode ser usado em experimentos que tenham como objetivo avaliar as consequências das mudanças de exposição à luz.

Ruido, iluminación y manipulación en recién nacidos en una UCIN / Noise, lighting and handling newborns in the UCIN

Resumen

Introducción: los recién nacidos críticamente enfermos requieren una Unidad de Cuidados Intensivos Neonatales (UCIN), situación que se enfrenta en un ambiente lleno de luz y ruido contrastante, así como de estimulaciones que repercuten en forma directa y no benéfica en su evolución y desarrollo.

Objetivo: determinar los niveles de ruido, iluminación y manipulación que reciben los recién nacidos críticamente enfermos en la UCIN.

Metodología: estudio transversal descriptivo para evaluar los factores ambientales a que se someten los recién nacidos críticamente enfermos como nivel de ruido, iluminación y manipulación por el personal. Se realizó análisis descriptivo con medidas de tendencia central y dispersión de variables cuantitativas, frecuencias y porcentajes de descriptivas. Muestreo no aleatorio por selección consecutiva. Se utilizó el paquete estadístico SSPS 17.0. Resultados: se monitorizó el ambiente de la UCIN durante 1 470 horas. Los niveles de luz fueron 309 amperes (54.4 683.5), nivel de ruido 60 decibeles (57.7-63.5) y promedio de intervenciones semanales 997 por paciente, que por categorías fueron realizadas: enfermería 916 (92 %) y médicos 81 (8 %). El turno con mayor ruido fue el nocturno con 59.2 decibeles, (matutino 60.5 y vespertino 57.2), el nivel de luz mayor en nocturno con 1115.1 amperes (matutino 166.2 y vespertino 622.2).

Conclusiones: los niveles de ruido, luz e intervención se encontraron muy elevados es decir, arriba de lo establecido por la Academia Americana de Pediatría.

Summary

Introduction: critically ill newborns requiring neonatal intensive care unit (NICU), a situation faced in an environment full of contrasting light and noise, as well as stimuli that affect beneficial but not directly in its evolution and development.

Objective: to determine the levels of noise, lighting and handling are critically ill newborns in the NICU. Methodology: cross sectional study evaluating the environmental factors that are subject critically ill newborns as noise, lighting and handling by staff. Descriptive analysis was performed with measures of central tendency and dispersion for quantitative variables and frequencies and percentages of descriptive. Non-random sampling by consecutive selection. We used the SPSS 17.0 statistical package.

Results: we monitored the environment of the NICU for 1470 hours. Light levels were 309 amperes (54.4 - 683.5), noise level 60 decibels (57.7-63.5) and average weekly 997 interventions per patient, which categories were made: Nursing 916 (92 %) and 81 physicians (8 %). The shift was more noise at night with 59.2 decibels (morning and evening 60.5 57.2), the higher light level to 1115.1 amps night (and evening matutino166.2 622.2).

Conclusions: the levels of noise, light and intervention were very high being above those established by the American Academy of Pediatrics.

Estudio sobre contaminación lumínica en el Parque Natural del Delta del Ebro / Study on light contamination in the parc natural del delta d'ebre

Por medio de este trabajo se presenta una investigación realizada en el “Parc Natural del Delta de l'Ebre”, cuyo objetivo fue determinar las condiciones lumínicas existentes y su afectación en elParque. La investigación consistió en: (1) Medición y cualificación de las condiciones lumínicas del Parque; (2) Estudio de las influencias que determinan variaciones lumínicas; y, (3) Relación de la información con las posibles afectaciones a la población biológica de la zona. Se encontró que los factores lumínicos que definían las condiciones nocturnas fueron: la luminancia del fondo de cielo, la iluminancia en el terreno, y la existencia de luminancias puntuales o sectoriales muy elevadas en el horizonte. Así también, después de llevar a cabo el tratamiento de los datos, se determinó que las condiciones lumínicas dependían de las condiciones de iluminación en el entorno, características e índice de emisión lumínica de los focos contaminantes, distancia desde el foco al área de estudio y la extinción atmosférica al momento de la medición.

This paper presents a research carried out in the “Parc Natural del Delta de l'Ebre”, and its objective was to determine the light conditions existing and it affectation on the park. The research consisted in: (1) Measuring and qualification of light conditions of the park, (2) Study of the influences that determine light variations and (3) Relationship of the information with possible affectations on the biologic population of the zone. It was found that the light factors that defined night conditions were, background sky luminance, terrain luminance and the existence of punctual or sector luminances very high on the horizon. Also, after processing the data, it was determined that light conditions depend on lighting conditions in the surroundings, characteristics and light emission index of contaminating lamps, distance from the lamp to the area of study and atmospheric extinction at the time of measuring.

Lesão inadvertida por foco cirúrgico / Inadvertent lesion due to surgical focus

Introdução: Entenda-se por lesão inadvertida aquela ocorrida inesperadamente, por acaso ou evento imprevisível, acidental e involuntária. Objetivo: Relatar os casos de dois pacientes que apresentaram, nos pós-operatório imediato, lesões teciduais de difícil explicação, que evoluíram para necroses localizadas, sua evolução clínica, o processo da formulação de hipóteses etiológicas e comprovação, sobre os quais se formulou a hipótese de queimadura causada pelo calor do foco cirúrgico. Relato dos casos: Duas pacientes submetidas a reconstrução mamária desenvolveram lesões bolhosas nas regiões operadas, atípicas, levando à investigação de tais causas. Formulou-se a hipótese de o agente causal das lesões ser o calor desenvolvido pelos focos cirúrgicos no centro das superfícies iluminadas. Além da biópsia da lesão de uma das pacientes, criou-se e aplicou-se um protocolo para mensuração da luminosidade e da temperatura desenvolvida sob as lâmpadas dos focos cirúrgicos. Procedeu-se à biópsia com o resultado compatível com o diagnóstico de queimadura. A análise dos focos demonstra termos atingido a temperaturade 63,5°C em 135 minutos, com as campânulas superpostas, sendo que à temperatura de 44ºC já se pode ter lesão tecidual. Conclusão: Comprovada a possibilidade de queimadura pelo calor do foco cirúrgico, configura-se a necessidade do médico estar atento ao uso adequado dos equipamentos médico-hospitalares, intervir oportunamente junto à indústria para a produção de equipamentos seguros, bem como fazê-los acompanhar de adequadas instruções de uso.

Introduction: The objective of this study was to report two cases of patients who presented in the immediate postoperative period, tissue lesions that are difficult to explain, which progressed to located necrosis, its clinical evolution, the process of formulating etiological hypotheses and evidences, on which it is made a chance to burn caused by the heat of surgical focus. Case report: Two patients submitted to breast reconstruction developed in 13 years after surgery of radical mastectomy, with signs of radiothermitis in the chest wall in the irradiated areas. Both patients developed bullous lesions in the regions operated, atypical, leading to the investigation of such causes. Raise the possibility of the causative agent of the injuries being developed by the heat outbreaks in the surgical center of the area illuminated. Apart from a biopsy of the lesion of the patients, it was created and applied is a protocol for measuring the brightness and temperature developed under the lights of surgical focus. This was the biopsy with the result consistent with the diagnosis of burn. The analysis shows outbreaks of having achieved a temperature of 63.5°C (146.3ºF) in 135 minutes, overlaid with cloches. Conclusion: From the knowledge of the possibility, given the biopsy and the measurement of temperature indicating the possibility of burns, the doctor must be attentive to the proper use of medical equipment.

Effect of short photoperiod on the leydig cells of rat's testis ultrastructural and immunohistochemical study

This study aimed to investigate by using electron microscope and immunohistochemistry, effects of short duration of light exposure on the Leydig cells of rat's testis. It tries to relate between seasonally changed environmental light factor and an important part of male reproductive system. Sixteen adult male albino rats were divided according to light exposure into control group [six rats] exposed to light: dark 12:12 h and group II [ten rats] exposed to light: dark 8:16h, daily for eight weeks. Light was provided by 20 watt fluorescent bulb. Testes Specimens were prepared for electron microscope and paraffin sections were stained for Fas and VEGF immunohistochemistry. Optical density of VEGF immunoreaction in Leydig cells was assessed morphometrically. In group II, the ultrastructural findings showed less mitochondria, smooth endoplasmic cisternae and secretary vesicles. Cytoplasmic vacuoles and irregularity of cell membrane of some Leydig cells were detected. Irregular nuclear membrane and condensation of nuclear chromatin were seen. Immunoreactivity for Fas was positive in some Leydig cells of group II. VEGF immunoreaction was decreased in many Leydig cells and this was proved by a significant decrease in mean optical density of VEGF immunoreaction. Short photoperiod exposure [which reflects short days of the year] may result in hypofunction of the Leydig cells in rat's testis with possible consequent decreased testosterone secretion and reproductive regression. So, seasonal fluctuations in Leydig cells morphology and function may serve to synchronize reproduction with favorable environmental conditions

influence of exposure to light and dark environment on platelet concentrates during storage

There is increased demand for stored platelet concentrates [PCs] for therapeutic transfusions. Despite all efforts to simulate the physiological environment Loss of the platelet functionality due to platelet activation occurs during preparation and storage of PCs "platelet storage lesion" [PSL]. Intensive investigations are currently undertaken to improve the storage of PCs however, the quality of the stored platelets is still questionable. Was to compare the influence of light and dark environment on the physiological function of routinely prepared random-donor PCs. And to teste the changes in platelet indices [platelet count [PLT count], and mean platelet volume [MPV]J, pH, lactic acid dehydrogenase [LDH] levels, the release of alpha-granule content through cell surface expression of specific activation-dependent antigens GPIIIa [CD 61], P- selectin [CD62] and, platelet membrane glycoprotein GP Ib [CD42 alpha] and GP IIb-IlIa [PAC1] in the PCs. Platelet concentrates were prepared using 450 ml of whole blood collected from 20 adult random volunteer male donors divide into two bags. The first one was left in continuous light exposure [light group]. The other one was raped in aluminum foil to avoid exposure to light [Dark Group]. Both bags were placed at room temperature for 5 days Platelet indices [PLT, MPV], pH, lactic acid dehydrogenase levels in addition to the expression of activation antigens CD61 and CD62 along with modulation of platelet membrane glycoproteins [GP] Ib [CD42 alpha] and IIb-IIIa [PAC1] in the PCs were measured on day 1 and day 5 of the storage period for both groups. The differences [delta] in these parameters for both groups were compared. The platelet indices [delta PLT count, and delta MPV "which reflects change in the platelet morphology"], delta pH, delta LDH, in addition to the activation markers [delta CD42alpha, CD61, CD62, and delta PAC1] were significantly lower in the dark Group compared with the Light group The most significant changes were in the level of the released LDH [P= .000] and the production of CD62 [[P= .00]. The PLT count significantly decreased in both groups after 5 days of storage. However, the platelets MPV significantly decreased in the light group only, which may be due loss of the large sized platelet during storage. There was statistically significant increase in LDH production in the light group [P= .000] "which is used as a marker for PLT lysis", in addition their pH also significantly decreased. In the dark Group, although there was a significant increase in the production of LDH, but it was statistically less significant than in the light group [P= .0] so that it may be buffered by the plasma and did not reflect on the changes in the pH in this group. There was a statistically significant influence of pH changes "as an independent variable" in the PCs on the changes in MPV "as a dependent variable" in both groups. However, there was no such influence regarding the PLT count. In the light group, the platelet activation markers CD61, CD62, and PAC1 were significantly increased in the PCs at day 5 compared to day 1. In addition, CD42alpha, was significantly decreased. While in the dark Group, there were no significant changes in those parameters, except for PAC1 which was significantly decreased although difference was less than that in the light group. In this study, platelets stored in light environment seemed to be more active with more platelet storage lesion [PSL], than platelets stored in dark environment. Platelet activation was associated with an increase in the, pH, LDH production and release of alpha-granule content and modulation of platelet surface glycoproteins. All these parameters may affect the post infusion quality of the stored platelets

Ergoftalmología: análisis de los factores que inciden en la astenopía de los trabajadores de inspección visual en la industria electrónica de Ciudad Juárez / Ergophthalmology: analysis of factors affecting asthenopia of visual inspection workers in the electronics industry in Ciudad Juárez

La Ergoftalmología, ciencia que nace de la unión de la ergonomía y la oftalmología, trata de optimizar las condiciones de trabajo en relación a la salud visual de los trabajadores. Esta investigación se ubica en ese campo del conocimiento. El objetivo general de éste proyecto fue demostrar que las condiciones de trabajo (iluminación, ángulo de visión y contraste entre objeto y superficie) y la aptitud visual (agudeza visual y cromaticidad), son factores ergoftalmológicos que influyen en la Astenopía de las personas que se desempeñan en actividades en el área de inspección visual, pertenecientes a empresas electrónicas. Los instrumentos de investigación utilizados fueron un cuestionario para medir la Astenopía, la prueba de agudeza visual de Snellen, la de Farnsworth-Munsell 100-hue para cromaticidad, el método LEST para iluminación, tangente del ángulo visual por la relación de minutos de arco de visión y el círculo cromático. Se validó una hipótesis de correlación entre lo factores ergoftalmológicos y la Astenopía, para lo cual se utilizó la prueba no paramétrica para tablas de contingencia. Se comprobó que los factores ergoftalmológicos analizados influyen en la Astenopía de los trabajadores del sector electrónico, concluyéndose que las condiciones de trabajo y la aptitud visual de los trabajadores presentan deficiencias que ponen en riesgo la salud visual de los operadores.

Evaluación de exposición ocupacional a agentes físicos, del puesto de trabajo del operador de caldera del Instituto de Salud Pública de Chile / Evaluations of occupational exposure to physic agents in caldera's of Institute of Public Gealth of Chile

El Operador de Caldera se encuentra expuesto a distintos agentes físicos como: ruido, calor e iluminación deficiente, realizándose evaluaciones de acuerdo a la legislación vigente, Decreto Supremo N° 594 del Ministerio de Salud de Chile. Se tomó como base para la evaluación, el generador de vapor ubicado en la Unidad de Energía. El resultado de dichas evaluaciones mostró que el Operador de Caldera no está expuesto a calor, que la sala de caldera presenta deficiencias de iluminación y que el ruido ocupacional se encuentra al límite de los valores permitidos por el Decreto Supremo N° 594.

A ergonomia e as doenças ocupacionais do cirurgiäo dentista: Parte III: agentes químicos e biológicos / Ergonomic and ocupational disease in dentistry: Part III: chemical and biological agents

Muitos säo os produtos químicos encontrados nos consultórios odontológicos. Os produtos químicos, quando manipulados inadvertidamente, podem provocar danos à saúde do cirurgiäo-dentista, como por exemplo maior, temos o mercúrio, que se manipulado inadvertidamente pode causar danos irreparáveis ao organismo humano. Além dos produtos químicos o dentista está exposto a uma grande variedade de microorganismos veiculados pelo sangue e pela a saliva de seus pacientes. Esses microorganismos podem causar várias doenças, como um resfriado comum, uma pneumonia, uma tuberculose, uma hepatite B, e muitas outras. Os autores mostram quais as doenças causadas pelos agentes químicos e agentes biológicos a que está exposto o dentista em um consultório, discutindo como prevení-los

A ergonomia e as doenças ocupacionais do cirurgiäo dentista: parte 1 - introduçäo e agentes físicos / Ergonomy and the occupational diseases of the dentist: part I - introduction and physical agents

A medida que o trabalho torna-se mais dependente da técnica, o número de acidentes e doenças ocupacionais aumentam de maneira impressionante. Sendo o cirurgiäo dentista um trabalhador que usa e depende cada vez mais da técnica, está também exposto a um risco muito grande de contrair doenças profissionais e doenças do trabalho. Dentre os riscos a que odontólogo esta exposto diariamente, pode-se citar, os agentes físicos. Este agente causador de doença ocupacional e sua prevençäo seräo abordados no presente trabalho

Avaliaçäo da degradaçäo das soluçöes de processamento Kodak Dental, utilizando recipientes protegidos (plástico) e desprotegidos (vidro), sumulando condiçöes de trabalho em consultórios odontológicos / Evaluation of decay of the Kodak Dental processing solutions, using protected (plastic) and unprotected (glass) containers, simulating work conditions in dental offices

O presente estudo teve por finalidade estudar a degradaçäo das soluçöes reveladora e fixadora Kodak, prontas para o uso, processando filmes Kodak Ektaspeed (EP-21), com câmara escura portátil, sob duas condiçöes de experimentaçäo: com as soluçöes em recipientes de plástico opaco e com tampas (soluçöes protegidas), e recipientes de vidro (soluçöes desprotegidas, simulando as condiçöes de sua execuçäo em consultórios odontológicos. Os dados obtidos das radiografias produzidas pela comparaçäo da densidade óptica, densidade de volume de prata e análise subjetiva, proporcionaram resultados que permitiram-nos constatar que as soluçöes protegidas tiveram um período de utilizaçäo menor que as soluçöes desprotegidas (28 e 35 dias). O número médio de radiografias produzidas até a degradaçäo das soluçöes foi de 104 para as protegidas e de 130 radiografias para a soluçäo desprotegida. Ao longo do experimento näo foram sentidas alteraçöes na degradaçäo das soluçöes em funçäo da variaçäo da temperatura ambiente, do pH, da cor, como também da influência do ar e da iluminaçäo

Diagnóstico de riesgos laborales en la Empresa "Guayas Caribe" / Diagnostic of working risk in the Guayas Caribe industry

Se realizó un estudio de tipo descriptivo-exploratorio, con el fin de elaborar in Diagnóstico de Riesgos Físicos en la empresa "Guayas Caribe", ubicada en la Zona Industrial Los Guayos, Valencia, Edo. Carabobo. Dicha empresa es del tipo metal-mecánica, dedicada a la fabricación de guayas, utilizando como materia prima en un 90 por ciento alambre y 10 por ciento mecate; tiene una población trabajadora de 33 personas; de las cuales 32 son hombres y una mujer (secretaria); de los hombres, 4 trabajan en oficina y 28, en planta, los cuales están expuestos a diferentes riesgos. Se evaluaron cuantitativamente: a)Ruido, utilizando un sonómetro marca "Quest", haciendo mediciones de octavas de bandas en las diferentes máquinas para posteriormente elaborar un mapa de ruido; b)Iluminación, utilizando un fotómetro General Electric, para después levantar un mapa de iluminación por área de trabajo. Los riesgos Ventilación, Temperatura y Operacionales se evaluaron cualitativamente. Se realizaron 14 estudios audiómetros de 28 trabajadores expuestos al ruido; lo que representa el 50 por ciento. Al realizar el análisis de los resultados encontramos: en relación al ruido; los trabajadores están expuestos por encima de los niveles máximos permitidos para una jornada de 8 horas, el ruido generado es por falta de mantenimiento de maquinarias. Existen serias deficiencias de iluminación encontrandose los puestos de trabajo por debajo de 400 lux, que es exigido para estos tipos de trabajo. Entre las recomendaciones producto de este trabajo, podemos citar entre otras; la constitución del Comité de Higiene y Seguriodad, para que sean los mismos trabajadores los encargados de vigilar poor unas condiciones de trabajo ópt6imas que le permitan un adecuado desarrollo de sus tareas sin perjuicios para su salud, elaborar un programa de Seguridad Industrial en base a la Norma Covenin 2260-88

A survey of the thermal environment, sound and illuminance in an iron and a steel foundry and related health effects.

The thermal environment and the workers' physiological response to heat were monitored throughout the casting process in two foundries. Of the 86 thermal observations in the iron foundry, 25 (29%) exceeded the heat stress index set by Occupational Safety and Health Administration (OSHA) advisory committee in 1974. In the steel foundry during a steel casting the environmental thermal measurements remained above the standard. The workers' physiological indices of heat strain as measured by pulse rate and body temperature rarely showed excursions above limits recommended by World Health Organization (WHO) in 1969. The environmental noise levels exceeded the standard in certain foundry operations. A significant hearing threshold shift was observed at 4 kHz among the foundry workers when compared with non-exposed controls. The illuminance in both foundries was below values recommended by the illuminating Engineering Society, in 1977. The prevalence of lens and corneal opacities among workers in the iron foundry was 32.5% and 30.0% respectively, which was significantly higher than that of the workers in the steel foundry and non-exposed controls.

Efectos oculares de las radiaciones ultravioletas / Ocular effects of ultraviolet radiations

Bajo ciertas circunstancias, las radiaciones ultravioletas (UV) producen en el hombre fotoqueratitis y fotoconjuntivitis que corresponden respectivamente a inflamaciones de la córnea y la conjuntiva. La respuesta espectral para la fotoqueratitis corresponde a una curva con un máximo entre 270 y 288 nm y un umbral de energía radiada, para dichas longitudes, entre 50 y 100J/m2. Similares datos para la fotoconjuntivitis son, 260 mm y 50J/m2. Estos datos corresponden a recomendaciones, de la División 6 de la Comisión Internacional de Iluminación (CIE), basadas en los estudios realizados por diferentes autores, que son comentados a lo largo del presente trabajo