Journal of Health and Safety at Work

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Introduction: Introduction: Thermal comforts are one of the most human concerns in working as was as living environments in the past half century. Thermal comfort is the condition in which people are satisfied with the thermal environment, mentally. One of the new heating system employed in individual units is radiant heating system .The purpose of this study was to investigate the performance of radiant ceiling heating system and its impact on thermal comfort of workers.

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Material and Method: In the present analytical-descriptive study, the designed radiant heating systems were investigated in two repair and maintenance units, in Hamadan gas pipeline operation center. Firstly, the environment parameters, witch impact thermal comfort, were measured before and after using radiant heating system, in both understudy units. Then, wind chill index, thermal comfort indices, PMV and PPD were calculated. In addition, PPD and PMV were determined, based on workers subjective feeling by a questionnaire distributed among 22 workers.

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Results: According to the results, the radiant heating system in unit 1, has reduced the wind chill index by 42.3 Kcal/ m2.h, witch is not considered to be significant. In unit 2, wind chill index has been decreased by 109.3 Kcal/ m2.h, witch mean that thermal comfort has been changed from cold to an optimum environment. PMV n unit 1 went up by 37% after turning the system on, witch is equal to 17.24% increase in workers satisfaction. However, in unit 2, the workers satisfaction was 14.3% higher in comparison with unit 1.

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Conclusion: Due to large space of these industrial units, producing appropriate heating by convection mechanism is too difficult and expensive. The results confirmed that if radiant heating system applied based on scientific design principles they could be effective in promotion of thermal comfort due to heating surrounding surface by radiant and also reducing fuel consumption.

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Introduction: Requiring industries for implementing industrial waste management programs and planning for proper waste disposal is essential in order to achieve sustainable development. Therefore, industrial waste management program was done in Kavir Steel Complex, in Aran va Bidgol region to identify and classify industrial waste and also to present solutions for improving waste management. In this complex, production process is hot rolling steel and the product is rebar.

Material and Method: The preset study was conducted in Kavir Steel Complex. Following survey of production process and sources of waste, the type and volume of produced waste were identified and measured during 3 months. Then, the classification of wastes was done according to the Bazel Convention and Resource Conservation and Recovery Act (RCRA), and finally new industrial & health solid waste management program was presented.

Result: Considering the volume, industrial waste of production process in Kavir Steel Complex was between 130 to 180 grams per each ton of rebar. Main industrial waste included oxide of steel billet, industrial sludge, used oil and lubricant which were classified according to the RCRA: 8 materials with T code, 1 with C code, 5 with I code and 3 materials with C code.

Conclusion: The results revealed that the most amount of industrial waste in Kavir Steel Complex is the waste of steel billet and industrial sludge, and more than 90% of Kavir steel industrial waste were reused and recycled inside or outside of this complex. It is recommended that used oil to be transport and maintain in the safe containers.

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Introduction: Computer vision syndrome (CVS) is one of the most common health concerns associated with the extensive use of computers, particularly in the working environment. Since recent studies have shown the high prevalence of CVS, it is necessary to have an appropriate tool for assessing this prevalence. The present research aims to translate the CVS questionnaire and analyze its validity and reliability and assess the incidence of this condition among the staff members at Tabriz University of Medical Sciences.
Material and Methods: The translation of the main questionnaire into the Persian version was carried out in three steps. Two coefficients including the content validity ratio (CVR) and the content validity index (CVI) were used to evaluate the content validity of the questionnaire. The reliability of the questionnaire was examined using two methods including internal consistency (Cronbach’s alpha) and test-retest. In total, 240 participants were asked to fulfill the questionnaire in order to investigate the prevalence rate of CVS among the staff members of Tabriz University of Medical Sciences. After removing the ineligible ones, 219 questionnaires were examined.
Results: The internal consistency coefficient and Cronbach’s alpha coefficient were 0.91 and 0.89, respectively. Out of a total of 102 women and 117 men, only 19 women and 21 men did not have CVS. Among the studied symptoms, eye redness (78.1%), burning (76.7%), and headache (74%) were the most prevalent in the statistical population. No significant relationship was observed between the final score of CVS and gender.
Conclusion: In terms of validity and reliability, the questionnaire was found to be satisfactory. The prevalence of CVS among the staff members of Tabriz University of Medical Sciences was high (81%). To determine the etiologies, further research is needed.

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Introduction: In recent years, driver’s drowsiness has been one of the leading causes of road accidents, which can lead to physical injuries, death, and significant economic losses. Statistics show that an efficient system is needed to detect the driver’s drowsiness, that gives the necessary warning before an unfortunate event occurs. Therefore, this review study was conducted to investigate the studies on driver’s drowsiness sensors and to present a combination of diagnostic methods and an efficient model design.
Material and Methods: This narrative review study was conducted through a systematic search using “driver” and “drowsiness detection” as search keywords in indexing databases including Scopus, PubMed, and Web of Sciences. The search encompassed the latest related research conducted in this field from 2010 to September 2020. The reference lists were also reviewed to find further studies.
Results: In general, researchers evaluate driver’s drowsiness using three methods including vehicle-based measurement, behavioural measurement, and physiological measurement. The details and how these measurements are made make a big difference to the existing systems. In this study, which is a narrative review, the three mentioned measurements were examined using sensors and also the advantages and limitations of each were discussed. Real and simulated driving conditions were also compared. In addition, different ways to detect drowsiness in the laboratory were examined. Finally, after an analytical comparison of the methods of diagnosing drowsiness, a diagram was presented based on which an efficient and combined model was developed.
Conclusion: Taking into account the limitations of each of the methods, we need a combination of behavioural, performance, and other measures to have an efficient drowsiness diagnosing model. Such model must be tested using simulations and in real world situations.