Journal of Health and Safety at Work

Introduction: Heat stress in workplaces cause multiple problems such as thermal stresses, thermal discomfort and in more severe cases may lead to accidents and diseases related to excessive heat. The aim of this study was to evaluate heat stress adopting WBGT Index in some small enterprise in Qom city and also to examine the relationship between WBGT and physiological indices.

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Material and Method: This Cross-sectional study was conducted in 25 small workshops in Qom city including of 10 indoor and 15 outdoor workshops in August 2012. WBGT were measured according to the ISO7243 standard. The physiological responses including pulse rate, systolic and diastolic blood pressure were measured among 25 workers (one from each workshop).

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Result: The average WBGT index for indoor job were 27.55 Ċ among auto body repair, 27.45 Ċ in mechanics, 24.64 Ċ in painters, 26.73Ċ in welder and 25.89 Ċ in manufacturing doors and windows makers. For outdoor jobs as auto body repair, mechanics and painters it was 30.01 Ċ, and for welders and doors and windows makers 28.52 Ċ. Compared to the standard of ISO7243 WBGT all small workshops were higher than threshold limit. Auto body repair (30.22 Ċ) and painting (30.03 Ċ) workshops had highest WBGT. Average WBGT in auto body repair (as a job with most exposed to the open space and solar radiation) with welder and doors and windows, showed statistically significant differences T-test using WBGT with pulse rate, systolic and diastolic blood pressure did not have statistically significant (P>0.05). The findings indicated that workers are exposing to heat stress and doing more researches and representing preventive counter measures for the workers in this field are essential.

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Conclusion: Heat stress in almost all of the studied workplaces are higher than the recommended limits, and the outdoor workshops had the highest thermal stress, although heat stress did not show a significant correlation with the studied strains.

Introduction: Heat stress is considered as a serious risk factor to the health and safety of workers in most working environments, especially in outdoor works and jobs that workers are exposed to heat due to the working process. This study aimed to evaluate heat stress among workers of brick-manufacturing units in Qom city based on WBGT index as well as the relationship between WBGT and physiological indicators.
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Material and Method: The present study was conducted in 40 brick-manufacturing units in Qom city. WBGT measurements were performed according to ISO7243 standard. Physiological responses of 184 workers (up to 5 people per unit) and also atmospheric parameters were measured. The physiological responses included oral temperature, skin temperature, and temperature for the carotid artery of the ear, heart rate, systolic and diastolic blood pressure. Statistical analysis was done using SPSS software version 16.
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Result: Mean WBGT index for various brick-manufacturing jobs including firing, manual material handling, working with conveyors, molding, and tempering were 30.8 °C, 26.74 °C 26.58 °C and 24.25 °C, respectively and the average WBGT was estimated 27.98 °C. WBGT levels measured in all units exceeded the level provided in ISO7243 standard. The highest mean WBGT was belonged to kiln section (30.8 °C). The mean WBGT at three heights of head, abdomen and legs were not statistically different (using t-test). The correlation coefficients between mean WBGT and mean oral, skin and ears temperatures were 0.203, 0.319, and 0.490, respectively, with the highest correlation belonged to the carotid arteries of ears. Moreover, WBGT showed no significant association with the mean heart rate, systolic, and diastolic blood pressure (P-value>0.05). Indoor and outdoor WBGT index was significantly different (P-value<0.05).

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Conclusion: The level of heat stress in all brick-manufacturing units was higher than the recommended limits, and the workers in kiln unit were more exposed to heat stress, in comparison with other units. Therefore, special countermeasures should be adopted to control heat stress for this occupational group.

Introduction: Each year, many people suffer from numerous injuries and damages in construction industry. Determination of factors that cause the most problems in a process is the most important step to improve the situation. Pareto chart can be used to explore factors causing most of the problems. The aim of this study was to survey construction accidents in Qom city using Pareto chart.

Material and methods: In this descriptive-analytical study, all accidents related to construction industry registered during 2009-2012 in the social security organization of Qom city, were analyzed using Pareto chart and mini-tabs software.

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Results: According to the results, 73.3% of accidents are due to objects and workforce being fallen. About 73.3% of the events occurred among 20-40 years old people. Hands and feet injuries comprised 53.4% of the accidents. Approximately, 61.8 percent of accident occurred in the first six months of the year. Moreover, the highest percentage of accidents was happened on Wednesday (19.4), Saturday (18.8), while Friday (8.4) and Thursday (10.5) had the lowest percentage of incidents.

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Conclusions: Employing Pareto charts as a method for analyzing and identification of accident causes can have an effective role in the management of work-related accidents, proper allocation of funds and time.