مجله بهداشت و ایمنی کار
سال دهم شماره 1 (بهار 1399)

Nurses, in comparison with other occupations, expose higher job stress; therefore, satisfaction in this job and its characteristics is very important. The purpose of this study was to investigate the effect of occupational characteristics on job satisfaction and job stress with the mediation of emotional work among nurses in Shariati Hospital, Isfahan City.

This cross-sectional study was conducted among nurses of Shariati hospital in Isfahan city, in 1397. The population in this study was 180 people selected by Morgan method at about 118 nurses. The data were collected using the job characteristics, job styles, job satisfaction and emotional work questionnaires. The SPSS Ver. 20 and Smart pls 3.2.6 software were used for data analysis.

According to the results, the dimensions of job characteristics such as importance, identity, independence, feedback, and verity of skills on job satisfaction were obtained. Also, the occupational stress by mediating emotional work (superficial and deep work), based on statistical results ( t-test), the value   of 8.589 statistics for the impact of occupational characteristics on work emotional, the 6.381 effects of emotional work on job satisfaction and value of 17.382 for significant effect on emotional work on job stress were efficiently achieved  with  positive effect.

Based on mediating emotional work, the Job characteristics have a positive and significant effect on the nurses’ job satisfaction and job stress. Therefore, the hospital managers should pay more attention to the characteristics and satisfaction of job stress and emotion of the job. The management of job stress and job satisfaction was improved through the recognition of the features of work and emotional work as favorite policies.

Cranes are of the major causes of accidents in the construction industries. As human error mostly causes crane accidents, this study aims to investigate the human errors of tower crane operators in the construction projects using SHERPA and CREAM techniques.

In this research, first, all of the tasks of the tower crane operator were identified and analyzed. Then, adopting SHERPA technique, probable operator errors were identified in each task and the control modes and error probability were determined by CREAM technique. Finally, all the human errors risks were assessed and the actions for risk control were defined to control them in the acceptable level.

According to the SHERPA technique, 148 errors were identified in the crane operator tasks. The human error assessment showed that monitoring the anti-collision system with the risk probability of 0.0003 has the highest control factor, while monitoring the existing guards with the risk probability of 0.056 has the lowest control factor. Also, the important tasks with high human errors were monitoring the guards with the cognitive risk probability of 0.07 and the tasks with cognitive risk probability of 0.05.

The findings in this study indicated that using complementary qualitative and quantitative methods can provide identification and prioritization of identified errors. This can help the organization   to allocate limited organizational resources to control unacceptable risks and increase the efficiency and effectiveness eventually.

Hydrogen sulfide (H2S) is a toxic gas that has adverse effects on human health and equipment. One of the methods for eliminating of H2S gas is the use of adsorbent substrate. In this study, the effect of adding iron oxides including ferric (Fe2O3) and magnetite (Fe3O4) nanoparticles to ZSM-5 zeolite substrate was investigated on the efficiency of H2S elimination from the air stream.

In this study, Fe2O3 and Fe3O4 nanoparticles were impregnated in ZSM-5 zeolite in two weight ratios of 3% and 5%. The structural properties of the substrate were studied using XRD, BET and SEM. Then, the efficiency of substrate in removing H2S from air was studied while H2S gas was injected in to a pilot setup, in concentrations of 30, 60, 90 and 120 ppm at three bed temperatures of 100, 200 and 300 o C.

The accuracy of combination and the morphology of inoculated zeolite was confirmed using XRD and SEM. The BET test also showed that the loading of iron oxide nanoparticles on the substrate educed the substrate surface area. The results revealed that increasing the percentage of nanoparticles and increasing the temperature from 100 ° C to 300 ° C increase the time of breakthrough point. The maximum adsorption capacity was obtained equal to 44.449 (mgH2S/g zeolite) for ZSM-5/Fe3O4-5% substrate at 120 ppm concentration.

Iron oxide  nanoparticles  inoculated  in  ZSM-5  zeolite  substrate  increase  the  capability of eliminating of H2S gas at high temperatures and therefore can be used as a suitable method for the elimination of similar pollutants.

Among the pollutants present in the ceramic and tile industry, silica dust is particularly important, and many studies have investigated the effect of this material on the respiratory system. Many occupational exposures may result in a decrease in spirometric parameters.

In the present study, totally, 120 male workers and employees of the factory, who had work experience of over 5 years and were not changed during the study, were included. Demographic information, including age, height, weight, work experience, smoking status and spirometric indices,  were extracted from the medical records of the workers from different groups for 5 consecutive years. All spirometry tests were performed using the FUKUDA ST 300 digital spirometer (Italy) calibrated once a year. The generalized Estimation Equation (GEE) method was used to study the trend of changes in each of the spirometric indices more accurately. Research related data were analyzed using SPSS software version 23.

The trend of changes was only significant for the FEV1 / FVC and FEF indices; for other indexes, the trend of changes was only observed in some years. The trend of changes was not significant for the FEV1 index, but smoking had a significant effect on the changes in this index. So, the level of this index was lower for cigarette smokers.

In this study, a clear downward trend was not found in the spirometric indices over 5 years, and only the FEF1 / FVC and FEF 2575% indices markedly were reduced in some occupational units, but due to the decline in some indices as well as proving the bad effect of Silica dust and other compounds on the respiratory system, there was an urgent need to implement management and engineering controls and protect the workers in the workplaces

Hazard Identification, risk assessment and management have an important role in reducing potential risks in industrial settings. This research was done with the aim of identifying the hazard and evaluating HSE risks and providing a HSE management program for the Urea Unit of Shiraz Petrochemical Complex.

Firstly, hazard identification and qualitative risk assessment was done using FMEA technique and risky units were identified. Then, main events were identified and analysed as inputs of the Bow-Tie method. By identifying the strength, weakness, opportunity and threat factors, ranking and weighting them using the ANP method and Super Decisions software, a SWOT matrix was prepared and HSE management strategies were extracted.

The results showed that chemical leakage, falling from height and slipping were the most important incidents, and defect of control equipment, lack of attention to instructions, non-compliance with safety principles and human error were causes of these events. Also, ranking of weaknesses, strengths, opportunities and threats were 0.58, 0.2, 0.16 and 0.05, respectively.

Organizational opportunities with a weight of 0.124 were 4.8% higher than threats with a weight of 0.076. This shows that the company had a good situation in terms of achieving its goals.

This study was designed with the main purpose of examining the compatibility of the two indicators of wet bulb globe temperature (WBGT) and predicted thermal strain (PHS) in assessing the environmental conditions and the heat load imposed on the subjects.

In this cross-sectional study, 163 bakers were included in the study. Thermal stress was determined using the WBGT and PHS. At the same time, physiological responses of subjects were recorded, including tympanic temperature, heart rate and mean skin temperature. Finally, the predicted heat strain was evaluated and compared with actual values.

Based on the results, the WBGT index is accompanied with an underestimation and PHS with  an overestimation, compared to the tympanic temperature. In addition, the WBGT index with the core temperature and the predicted rectal temperature component of the PHS index are the most consistent (kappa value of 0.614 and 0.66, respectively). While the Kappa value is between the amount of water lost and the WBGT index, it indicates a mismatch (Kappa = 0.339).

The prediction of heat strains only based on the PHS index cannot reflect the actual heat load on individuals in thermal environments such as bakeries and it is associated with an overestimation. On the other words, this indicator is more suitable for indoor thermal environments, with minimal variation in individual and environmental factors affecting thermal stress

Todays, exposure to heavy metals is happened by being produced in various environmental, industrial processes. The production of metals finally results in air pollution as well as contamination in the food chain. There are harmful effects of heavy metals such as cadmium on different organs. Therefore, this study aimed to identify and quantify cadmium in biological samples using DLLME SFOD method.

Optimization of the underlying variables played a key role in the process including sample PH, chelator, extractor and disperser solvents, ion concentration, time and rate of centrifugation and extraction time. It was done by employing central composite design (CCD) of the response surface methodology. In the process of optimization, after setting a certain pH, Specific salt concentration and ditizon added to form a complex between the metal and the chelator. A mixture of extraction and dispersant solvents added to the sample. The organic and aqueous phase separations when centrifugation and vortex carried out, the sample vial transferred to a cold ice bath and the organic solvent floated on the aqueous solvent .The organic portion containing the analyte was injected into the analyzer apparatus.

Results:

 The results showed that variables such as sample PH, complexing solvent, extraction solvent, centrifugation effect and extraction time play an important role in the extraction of cadmium metal ion from biological samples. The optimized method with a minimum detection limit (LOD) of 2 μg / l and a concentration factor (EF) of 50 and a relative recovery (RR) of 1.06.26 used to extract cadmium from urine samples.

Conclusion:

 According to the pre-test results and the optimization process, they showed that in the three factors of sample PH, salt concentration and extraction solvent volume that play a more effective role in cadmium extraction by DLLME-SFOD method.

Introduction:

The effect of exercise program on the prevention of upper extremities musculoskeletal disorders has attracted the attention of researchers. On the other hand, in assembly workers, the risk of these disorders increases because the part of the body is used successively and without rest. The current study investigates the effect of 8 weeks of Kinesio Taping and sport program on grip endurance in female assembly workers of an electrical piece industrial manufacturer.

Materials and Methods:

The current study was used a descriptive-analytic, cross-sectional method among 40 female assembly workers. Participants are exercised and used Kinesio taping for two times per week at eight weeks. The endurance of the grip was determined before and after the intervention by a dynamometer and the maximum time (in seconds) that one was able to continue one third of the maximum voluntary contraction. The DASH questionnaire was used to assess upper limb extremities’ disability. Data were analyzed using SPSS Ver.20 and the P value was considered smaller than 0.05.

Results:

 In the present study, the mean of right and left hand grip endurance in kinesio type and exercise group before intervention were obtained 10.55 and 9.51, whereas, related results after intervention were obtained 20.55 and 16.18, respectively. Also the score of upper limb disability in kinesio type and exercise group before intervention were obtained 10.55 and 9.51 and after intervention obtained 20.55 and 16.18, respectively(P <0.05).

Conclusion:

 According to the results, sport exercise and kinesio taping, lead to the increase in the grip endurance time and decrease in the upper limb disability.