Journal of Health and Safety at Work

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Introduction: Nowadays, in many different fields of chemical agents several experimental researches is being done on volatile organic compounds using gas chromatography, which is time consuming and expensive methods. Photo ionization detector as an alternative method is used by researchers in this field. This feasibility study was conducted to replace the photo ionization detector with gas chromatography.

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Material and Method: In this study, after making pre-determined concentrations of Xylene, the results of measurements using photo ionization detector and reference method were compared. This comparison was done in 4 humidity levels and 3 concentration ranges.

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Result: The results showed significant differences in photo ionization detector readout and the reference method. However correlation coefficient of two methods were more than 0.99 in all cases regardless of the humidity rate.

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Conclusion: Although the results obtained by the photo ionization detector are different from those extracted from the reference method in the current study, due to linear response of the method correlation coefficient was at good level. Consequently, in case of studying concentration changes in a research, this alternative method would be applicable, otherwise calibration of the photo ionization detector with the target material is recommended.

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Introduction: The compliance of Health, Safety and Environment Management System (HSE-MS) requirements and proper HSE performance of employees, are the affecting factors on the organizations prosperity. The objective of present research was to determine the relationship between organizational culture and personnel HSE performance at Saipa Car Manufacturing Company.

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Material and Method: The present research was a deccriptive – correlative study. The Study population of this research were the manufacturing employees of Saipa car manufacturing company (N= 4865). Among the manufacturing employees, 365 employees were chosen as the sample beside on statistical estamination. Data was collected using a questionnaire which had three parts: demographic data, organazational culture and personnel HSE performance indicators. In order to convert the qualitative values of the questionnaire to the quantitative ones, the triangular Fuzzy numbers has been used. The data collected by observation and self- answering method then be analyzed using descriptive statistical tests and Spearman correlation coefficient, considering the relative importance of the indicators obtained form HSE experts’ comments.

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Result: Among the organizational culture indicators of Siapa car manufacturing company, control indicator (with the average score of 0.55) and among the personnel HSE performance indicators of Saipa company, performance indicator (with the average score of 0.66) had better situation, compared to other variebles. The results showed that there is a significant relationship between personnel HSE performance and organizational culture indicators except for Bonus System indicator (with the significant level of 0.112).

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Conclusion: Considering the significant relationship between personnel HSE performance and organizational culture in the studied company, paying more attention to the organizational culture will accordingly improve the personnel HSE performance. Moreover, by improveing and optimizing the cultural indicators, which have the greatest impact on personnel HSE performance a better organizational culture and personnel HSE performance mey be achived in the Saipa company in the future.

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Introduction: In the most industrial environment, workers are exposed to noise everyday. Exposure to this physical hazardous agent can cause immediate as well as delayed adverse effects. Cognitive performance decrement is one of the adverse effects of noise exposure which its main consequences is occupational accidents. This study attempted examine the effect of exposure to different levels of noise with harmonic indices of neutral, treble and bass on the cognitive performance.

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Material and Method: In this analytical-descriptive study, the cognitive tests were performed by 33 students, aged 23-35 years. During the tests, participants were exposed to three type of noise including neutral, treble and bass at 4 different levels of 45, 75, 85 and 95 decibels. In order to assess students cognitive performance, continuous performance test (CTP) software was employed, which investigated attrition and reaction time.

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Result: The results of this study revealed that exposure to neutral noises with Noise Harmonic Index (NHI) of +3dB at the frequency of 1000 Hz, the maximum percentage of attention (99.88 %) was belonged to Sound Pressure Level (SPL) of 95 decibels. Maximum percentage of attention due to exposure to the treble noise with NIH -105 dB at the noise frequency of 8000 Hz (100%) and bass noise with NIH of 407 dB at the frequency of 500 Hz (99.92%) were belonged to the SPL of 95 and 85 dBA, respectively. Moreover, the result showed that the effect of bass noise with NIH of 4.5 dB and frequency of 500 Hz on reduction of attention were more than treble noise with NIH of -105 dB and frequency of 8000 Hz. Under exposure to neutral noise with NIH of 3 dB and frequency of 1000 Hz, the longest reaction time (2.594 Second) was observed at the SPL of 85 dBA. The longest reaction time for treble noise with NIH of -105 dB and frequency of 8000 Hz (2.786 Second) and for the bass noises with NIH of 4.5 dB and frequency of 500 Hz (2.594 Second) were also belonged to the SPL of 85 and 75 dBA, respectively.

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Conclusion: The results showed that bass noises (frequency of 500 Hz) increased reaction time, in comparison with treble noises (frequency of 8000 Hz).

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Introduction: Individuals’ jobs performance is one the most important factors in industries and organizations. The aim of the present study was to investigate the simultaneous effect of exposure to noise, lighting and heat stress on the workers’ job performance.
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Material and Method: In this analytical-descriptive study, 30 employees of the auto parts manufacturer, in Tehran city, were chosen by simple random sampling. By controlling and limiting confounding factors, the simultaneous effect of noise, lighting and heat stress on the participants’ job performance was investigated, using tow series of mental and manual testes. Data were analyzed by SPSS software version 18, using descriptive statistic, ANOVA and Tukey testes and also person correlation coefficient.
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Result: The results showed that by increasing the noise and heat stress (P = 0.046, r=0.344) and decreasing of lighting (P =0.008, r = -0.472), the required time for performing the Minnesota placement test has been gone up. Moreover, the result revealed that by increase in noise and heat stress (P = 0.007, r = 0.478) and decrease in lighting (P=0.003, r = 0.523) the required time for competing hand tool dexterity test has been also increased at surface and mid level.
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Conclusion: Finding of the present research manifested that increase in noise and heat stress and also reduction in lighting lessen the speed of manual tests and time and accuracy of mathematical calculations. Therefore this result confirm the effects of various environmental factors on individuals’ job performance, in a way that by variation of different environmental factors, time of manual test and time and accuracy of mental tests would be changed.

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Introduction: Job design approach is one of the significant concepts in ergonomics Experts believe that integration of macro ergonomics and job design can lead to improved productivity in the organizations. Therefore, this study examined the relationships between job design, performance and job satisfaction.

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Methods and Materials: This cross - sectional study was done in 11 branches of one of the bank in Hamadan. Job Design Questionnaire, Job Satisfaction Questionnaires and Bank Performance Indicator were used in order to collect data. spearman correlation coefficient was used for determining the correlation between each two variables.

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Results: This study showed that the motivational approach was the minimum approach (3.8%), and the mechanical approach, was the dominant approach (74.7%) in the study branches and the majority of branches had an average level of job satisfaction. Moreover, there was a significant positive correlation between job design (motivational and cognitive approaches) and job satisfaction. In addition, the results showed that between job design (Motivational approach) and satisfaction were significantly correlated with performance, (p = 0.05).

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Conclusion: Regarding the role of job design in job satisfaction and employees, performance, it can be stated that job redesign towards a motivational approach and considering the principles of ergonomics in the workplace, can play an important role in efficiency and productivity of an organization.

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Introduction: The present study aimed to test a model of the relationship between management commitment to safety and consciousness with unsafe performance,considering the mediating role of safety self-efficacy.

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Material and Method: Research design was the correlation throughStructural Equation Modeling (SEM) and the sampleconsisted of 265 employees of an industrialcompany who were selected by stratifiedrandom sampling method. Participants of this study completedsafety climatescale, short form of NEO personality questionnaire,safety self-efficacy scale, and unsafe performance questionnaire.Reliability and validity of the questionnaires were reported as acceptable. Evaluation of the proposed model was done by SEM through AMOS-21and SPSS-19 software packages. In addition, Preacher and Hayes’ SPSS Macro program was used for testing the mediating role.

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Result: The results showed that the proposedmodel fit the data properly.Management commitment to safety and consciousness had direct effect on unsafe performance and safety self-efficacy.Moreover, the mediating effect of safety self-efficacy in the relationship between management commitment to safety and consciousness with unsafe performancewas confirmed.

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Conclusion: Overall, organizations canreduce unsafe performance and consequently occupational accidentsby increasing the management commitment to safety and employees’ consciousness and also training of employees and supervisors to reinforce their safety self-efficacy.

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Introduction: The present study aimed to investigate the relationship between safety climate and safety performance with respect to the mediating effect of safety knowledge and safety motivation.
 

Material and method: The study population was a sample of 354 subjects chosen by Cochran formula among all 4252 employee in Sarcheshmeh copper complex in Rafsanjan, 2015. The participants were selected according to stratified random sampling. Data collection was done by four questionnaires (safety climate, safety knowledge, safety motivation, and safety performance).The Cronbach's alpha and composite reliability (CR) were used to evaluate the reliability of the study tools and the coefficient of all variables were acceptable with values of higher than 0.8. Moreover, validity of the questionnaires was confirmed by convergent validity and divergent validity, R-square, effect size (f2), and Q2 criterion. The Average Variance Extracted (AVE) was greater than 0.4 which is relatively acceptable. The obtained data were analyzed using SmartPLS software. 
 

Result: Kolmogorov-Smirnov test was used to investigate the normality status of variables distribution. Furthermore, Structural Equations Method (SEM) was adopted to test the research hypotheses.The results confirmed all the research hypothesis and showed safety climate direct effect on safety performance. Moreover, safety motivation and safety knowledge have mediating role in the relationship between safety climate and safety performance. Safety motivation can also mediate the relationship between safety knowledge and safety performance.
 

Conclosion: Overall, it is recommended to improve safety climate, considering its influencing components. Employees' safety knowledge and safety motivation should also be promoted. Additionally, it is recommended to determine other personal and organizational parameters and include them into the model. By determining the mediating variables, their role in the safety performance can be investigated.

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Introduction: Heat stress is one of the Hazardous physical agents in the workplace, which can cause impairment of cognitive performance. The current study aimed to evaluate the effect of different levels of heat stress on attention and reaction time in a laboratory condition.

Material and Method: This experimental study was done among 33 students included 17 males and 16 females. Mean age of the participants was 22.1(SD=2.3). Attention and reaction time parameters were evaluated using the continuous performance test and  reaction time measurement device respectivlely, after exposure to different heat levels (22°C and 37°C). Data were analyzed using ANOVA test and SPSS 20 software.  

Result: The results of tests attention and reaction time showed that the average of attention percentage was decreased and the average of reaction time increased by increasing the heat level, with a  statistical differences of  (P˂0.001) in both cases. Attention percent in terms of exposure to 22°C temperature was significantly higher than 37°C (P˂0.001). But, reaction time was significantly higher than with the exposure to 37°C temperature than 22°C (P˂0.001).

Conclusion: The results of this study showed that, heat by increasing reaction time and decreasing attention leading to an impairment  in the individual’s cognitive performances. Therefore, in jobs such as control rooms and various industries that need attention, concentration and quick reaction, it is necessary to consider and optimize the heat conditions in order to increase the level of attention and decrease of reaction time.

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Introduction: Exposure to vibration as one of the consequences of industrial noise or the use of vibration generators can cause discomfort, reduce the efficiency and level of safety in workplaces. Therefore, in this study, the effect of whole body vibration on individual’s mental performance and response time was investigated.

Material and Method: In this study, 40 male students of Tehran University of Medical Sciences were selected randomly and divided into two 20 subjects groups. Each group participated in two Pegboard Board and Math Calculations tests. Subjects in each stage of test were exposed to whole body vibration with acceleration in 0.8 and 1.1 m/s2 as well as background mode without vibration and were investigated response time and mental performance.

Result: In the present study, the mean response time to the manual Purdue Pegboard test in the vibrational acceleration of 0.0, 0.8 and 1.1 m/s2 with a decreasing trend was 197.55 ± 2.7, 176.25 ± 5.38 and 177.58 ± 2.92, respectively, which results in a significant reduction in the accuracy of the test. Also, the results showed that whole body vibration does not affect mental performance in shallow levels. But, in the intermediate and deep levels, this difference is statistically significant (p <0.001).

Conclusion: Based on the results, whole body vibration is an effective factor in individual’s response time and mental performance, which can lead to a reduction in the accuracy of the work.

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Introduction: Todays, the improvement and optimization of the safety performance are essential and important for control and prevention of accidents in the industry. The purpose of this research was to assist a hybrid cycle power plant for identification and prioritization of the influencing factors in enhancing safety in order to reduce risks and to improve system performance.  
Material and Methods: In this descriptive-analytical study, influencing factors were classified within three main categories of human, equipment, and managment, and 14 sub-factors was screened and selected by experts using Fuzzy Delphi method. Then, fuzzy DEMATEL method was adopted to determine the relationships, the intensity of affecting and being affected factors, and the analytical network process method for weighting and prioritization the factors.
Results: The findings of the fuzzy DEMATEL method showed that “Managerial”, “equipment” and “human” factors are respectively influencing factors on the improvement of safety performance. “Managerial factors” is the most influencing and “Human factors” is the most influenced one. Based on the results of fuzzy analysis network process method, “human factors” is the first priority among the main factors, and “employee motivation”, “system of control and prevention”, “work team spirit”, “individual skills” and “Individual protection equipment” sub-factors are respectively the first to fifth priorities were according to their weight.
Conclusion: “Human factors” re the most influenced factor and the main problem of the organization, which can be improved by the most influencing “managerial” factor. The success or failure of the safety performance in the power plant depends on better management of the “human factors” and managers need to motivate employees to improve safety performance.

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Introduction: Throughout the world, many efforts have been made to provide suitable tools for achieving sustainable urban development and the achievement of a sustainable city. Establishing a Health, Safety and Environment Management System (HSE-MS) is one of the tools for achieving sustainable urban development. Measuring the performance of an organization in the HSE area is a precondition for continuous improvement, which is the spirit of the new HSE management systems. Therefore, the main purpose of this research was to provide a practical model for quantitative ranking of different areas of Tehran municipality in terms of HSE performance with using of multi-criteria decision-making method.  
Material and Methods: In this descriptive-applied study, after determining functional axis and performance evaluation indicators related to each of them (29 functional axis and 154 performance evaluation indicators), through designing a questionnaire and based on the views of the expert group, weight of functional axis and performance indicators were determined using a hierarchical process analysis technique.
Results:  In this study, the weighted value for functional axis of the process based HSE in comparison to the result based HSE were higher. “Commitment and Leadership” and “HSE Certificate of Occupations” for the process based HSE, “Safety” and “Health” for the result based HSE, and “Economic Sustainability” and “Architecture and Urbanism” for urban management had the higher and lowest weighted values.
Conclusion: The results of assessment and validation of selected indicators and functional axis showed that in designing and determining the HSE performance assessment model of municipalities, in addition to the axises and indicators of the HSE domain, factors affecting urban management can have a significant impact on the performance of municipalities in the field of HSE.

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Introduction: Along with the extensive production and use of various pesticides for controlling pests and enhancing the production of agricultural crops, there is a growing concern about the adverse effects of these toxic materials on human health. Therefore, the development of sensitive, selective, and accurate methods for continuous assessment of pesticides concentration in occupational and environmental fields and comparing them with national and international standards is of great importance. This study was aimed at synthesis and application of molecularly imprinted polymer as a selective sorbent for residue determination of two pyrethroid isomers in biological samples.  
Material and Methods: The MIP particles were prepared by a non-covalent approach using permethrin as a template, chloroform as progen solvent, methacrylic acid as functional monomer and ethyleneglycol dimethacrylate as cross-linker, at 55 °C for 18 hours in an oil bath. Field emission scanning electron microscopy was used to investigate the morphology and size of polymer particles. Afterward, the critical parameters, which could affect the recognition properties of synthesized MIP, were investigated and optimized under the selected operational ranges for the highest adsorption and recycling yield in solid-phase extraction of permethrin in biological samples
Results: using precipitation polymerization technique, uniform and spherical particles with the nano-ranged diameter (less than 21.2 nanometers) were obtained. Under the optimized condition, the designed molecularly imprinted solid-phase extraction (MISPE) technique exhibited great potential for the extraction of pesticide isomers in the real sample. More than 93 % of the recovery obtained from spiked urine samples. The linear calibration curve was obtained from 20-120 μg.L-1 (R2=0.99) and the detection limit was less than 6 ppb for both isomers. The presence of interferences had no effect on the selectivity of the method up to 100-fold.
Conclusion: employing the molecular imprinted solid-phase extraction method along with the high-performance liquid chromatography technique resulted in a selective and sensitive approach, suitable for quantitative monitoring of the desired pesticide in complex biological samples.

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Introduction: Along with the extensive production and use of various pesticides for controlling pests and enhancing the production of agricultural crops, there is a growing concern about the adverse effects of these toxic materials on human health. Therefore, the development of sensitive, selective, and accurate methods for continuous assessment of pesticides concentration in occupational and environmental fields and comparing them with national and international standards is of great importance. This study was aimed at synthesis and application of molecularly imprinted polymer as a selective sorbent for residue determination of two pyrethroid isomers in biological samples.  
Material and Methods: The MIP particles were prepared by a non-covalent approach using permethrin as a template, chloroform as progen solvent, methacrylic acid as functional monomer and ethyleneglycol dimethacrylate as cross-linker, at 55 °C for 18 hours in an oil bath. Field emission scanning electron microscopy was used to investigate the morphology and size of polymer particles. Afterward, the critical parameters, which could affect the recognition properties of synthesized MIP, were investigated and optimized under the selected operational ranges for the highest adsorption and recycling yield in solid-phase extraction of permethrin in biological samples
Results: using precipitation polymerization technique, uniform and spherical particles with the nano-ranged diameter (less than 21.2 nanometers) were obtained. Under the optimized condition, the designed molecularly imprinted solid-phase extraction (MISPE) technique exhibited great potential for the extraction of pesticide isomers in the real sample. More than 93 % of the recovery obtained from spiked urine samples. The linear calibration curve was obtained from 20-120 μg.L-1 (R2=0.99) and the detection limit was less than 6 ppb for both isomers. The presence of interferences had no effect on the selectivity of the method up to 100-fold.
Conclusion: employing the molecular imprinted solid-phase extraction method along with the high-performance liquid chromatography technique resulted in a selective and sensitive approach, suitable for quantitative monitoring of the desired pesticide in complex biological samples.

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Introduction: Assessing health, safety, and environment (HSE) performance based on up-to-date analytical models like resilience engineering, especially in automobile manufacturing companies, affected by the trilogy of HSE factors and functions, is of crucial importance. Therefore, this study was to review the factors effectively involved in HSE management performance assessment based on resilience engineering in automobile manufacturing industries.
Material and Methods: To collect and classify the data, many relevant articles and procedures published in journals or presented at seminars were researched and cited. In this study, reliable online databases, including Google Scholar, Web of Science, Scopus, and PubMed were searched to meet this purpose. Other databases in Farsi such as Magiran, CIVILICA, and Scientific Information Database (SID) were also employed. Accordingly, a total number of 211 articles were extracted and filtered in terms of content and topic by a team of four HSE senior experts, whereby irrelevant studies were deleted, the full text of each relevant article was more closely considered, and finally 18 studies were selected and thoroughly examined.
Results: The findings from these 18 articles revealed that the HSE would be influenced in various industries by factors such as organizational culture, learning and training, political-economic variables, workforce qualifications and skills, strategic and large-scale programs of organization plus its assets and financial resources. In automobile manufacturing industries as well, circumstances might emerge because of some extra-organizational threats and intra-organizational weaknesses, whereby the appearance of deficiencies in various processes and even the functions of the HSE as a whole would be impaired. Of the many external factors, one could mention economic sanctions, large-scale socioeconomic problems, and lack of materials and production equipment. The internal problems would also range from production reduction and cuts in budgets earmarked for different management departments to a rise in the number of accidents and diseases, soaring medical treatment costs, as well as growing expectations in employees, which together impact the HSE management performance.
Conclusion: Regarding the studies conducted on various models presented so far in the area of resilience, it was concluded that the HSE performance of organizations intended to prevent and control risk factors were by no means distinct from other management factors and strategic decision-making in an organization. Rather, the HSE indicators could be impacted by many extra- and intra-organizational factors. Based on the models surveyed, it would be essential to consider the concept of resilience in HSE management. The reason for this is that the idea of the HSE would appear to be an issue of less virtue and importance in various stages and situations in the lifecycle of an organization, which is not consistent with the HSE management system and does not keep pace with the influencing factors.

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Introduction: The oil and petrochemical industries had been amongst the first industries which developed the HSE-MS. This system aims to maintain and protect human resources along with reducing the environmental impact of the industry. Although it has been mulling over this system in a plethora of studies, unfortunately, most of the assessments have been carried out in a qualitative manner. In recent years, the evaluation of the performance of HSE-MS has been limited due to the lack of appropriate quantitative evaluations.
Material and Methods: In the present study, the development of criteria and sub-criteria of health, safety and environment management system was investigated using a different approach. Using the opinion of experts and according to the performed categories, a questionnaire was developed to determine the pairwise comparisons. Decision making trial and evaluation (DEMATEL) technique was used to determine the relationships between the criteria and network analysis method was used to determine their importance weight. the developed methodology was then evaluated and compared between two factories in a case study.
Results: The performance evaluation showed that the leadership and commitment criterion with a final score of 1.8; Risk assessment and management with a final score of 0.8; Planning criterion with a final score of .0.40; Policy criterion with final score of 0.33, Organization, resources, and documentation with a final score of 0.31, implementation and follow-up with a final score of 0.22, and Evaluation and Review criterion with a final score of 0.12 were ranked from the first to the seventh, respectively.
Conclusion: The results of the study demonstrated that the most important criterion for health, safety and the environment is leadership. The significant difference between the final score of the leadership criterion and the other criteria reflects its crucial importance in HSE-MS performance evaluation. Participation of employees, allocation of appropriate funding and support of innovativeness are factors to be implemented in order to improve HSE-MS program as a better and successful management.  

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Introduction: Safety situation awareness is an important element affecting operator's reliability and safety performance, which is influenced by various variables. Identification of these variables and their relationship will play a major role in optimizing control measures. The present study was conducted for this purpose.
Material and Methods: This study was based on the situation awareness, expert’s opinions and use of a Fuzzy multi-criteria decision-making method. Triangular fuzzy numbers was used to quantify the experts' judgments and to reduce the errors that result from theirs’ subjective evaluation on the relationships between the variables.
Results: The results showed that the studied organizational variables together with "safety/g knowledge" and "experience in job/specific task” are the most important predictive variables of situation awareness. Among the organizational variables, "Organizational Safety Attitudes", "Safe System Design" and "Education" are the most important determinants of safety situation awareness.
Conclusion: Fuzzy logic was used to aggregate expert opinions to determine the most important variables affecting situation awareness and their cause-effect relationships. Organizational variables are the main determinants of situation awareness. To improve situation awareness, the best results are obtained by modifying effective root variables, i.e., organizational variables and some individual variables.

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Introduction: Each country needs to preserve its human capital through preventing accidents for its development. Therefore, this study is carried out to study the relationship between safety investments and safety performance indices considering the interactive effect of the project hazard level in construction industry.
Material and Methods: This study was conducted using multiple case studies in 5 major construction worksites, in Tehran, in 2019. Data was collected using questionnaire, checklists and interview as well as evaluating the safety documents. The data analysis in this study was carried out using SPSS 18.
Results: There was a strong inverse correlation between safety investments (total safety investment, basic safety investment, and voluntary safety investment) and accident frequency rate (AFR) (r=-0.936, P-value<0.05), and there was a direct strong correlation between safety investment and safety performance (P-value<0.05, r=0.939). Also, the effect of various safety investments on safety performance indices under various project conditions (project hazard levels) was not the same; when the project hazard level was high, the effect of safety investments on safety performance was higher.
Conclusion: Increasing safety investment improves safety performance through decreasing the accidents. Also, investment in both safety components (basic safety investment and voluntary safety investment) might improve safety performance. The results of the current study can be used as a basis by the contractors and construction companies to invest in safety and to determine proper budget for managing safety of construction projects.

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Introduction: The acoustic performance of natural fiber adsorbents has been investigated in numerous studies. A part of these materials show a poor adsorption within the frequency range of less than 1000 Hz. In the present study, attempts were made to investigate the effect of layout sequence of double-layered composites consisting of natural and synthetic fibers on improving the acoustic adsorption coefficient of natural fiber in the low-frequency range (63 to 1000 Hz) using the numerical finite element method.
Material and Methods: In this study, the finite element method and the Johnson-Champoux-Allard model in COMSOL software version 5.3a were used to investigate the acoustic performance of the double-layered composites consisting of natural and synthetic adsorbents. The acoustic absorbers under study included date palm fiber, polyurethane foam and cellular rubber. Each double-layered composite included a date palm fiber with 10mm in thickness and a synthetic adsorbent (polyurethane foam or cellular rubber) with 10mm in thickness. In sum, four double-layered composite structures with different layouts of adsorbents in each structure were studied.
Results: The location of natural fiber can play a critical role in the acoustic performance of the double-layered composite structures such that comparing the studied double-layered composites revealed that when the natural fiber was the first layer exposed to the normal sound in the double-layered composites with 20mm in thickness, the trend of acoustic performance was approximately the same as the single-layered composite of natural fiber with 20mm in thickness; but in the composite structures, when the synthetic adsorbent was the first layer exposed to the sound, the trend of acoustic absorption was improved.
Conclusion: On the basis of the results, the double-layered composite structure with a higher-density and lower-porosity upper layer showed a better acoustic absorption trend than the single-layered composite including the natural adsorbent.

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Introduction: Comprehensive and reliable performance evaluation of organizations has always been one of the main concerns of stakeholders and managers of organizations. Performance evaluation can raise awareness of the progress made in improving the performance of any organizations, especially in the field of health, safety, and environment (HSE) and thus, create the necessary motivation and opportunity to improve the quality of HSE performance. National quality awards and excellence approaches emphasizes the fact that survival in global competition requires improving the performance of organizations on a global scale. The EFQM enterprise excellence model, as a comprehensive tool with a comprehensive approach to all aspects of organizations, helps managers to understand their organization well.
Material and Methods: This study was conducted in Tehran Industrial Group in 2018, during which the performance of this industrial group in the design and construction of one of the dams in the south of the country was evaluated and analyzed. The data collection tool was a standard self-assessment questionnaire based on the EFQM enterprise excellence model, the validity and reliability of which was tested by Cronbach’s alpha coefficient at 0.971.
Results: In terms of “enablers” criteria, the leadership dimension, with a score of 76.36, obtained the best percentage of scores, while the processes criterion with a score of 72.04 had the lowest percentage of scores. This dimension, along with staff, resources, and partnership dimensions, needs to be improved. In the field of “results” criteria, the key performance results with 79.77 points had the best percentage and the customer result dimension with a score of 69.13 had the lowest, indicating that the organization should improve these sectors.
Conclusion: The results indicated the suitable status of the organization in terms of the criteria of excellence model. The results of this model are generally used for systematic analysis of the organization in order to achieve a comprehensive view of the organization and its challenges.

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Introduction: There are several generic and specific models to assess the individual job performance (IJP). While these methods may provide the valuable information, none of them cover the complexity and wide range of the behaviors which express the IJP. This review study aimed to identify all existing models and incorporate them to achieve a comprehensive conceptual model to assess the IJP. 
Material and Methods: Databases such as PubMed, Scopus, Embase, and ProQuest were systematically searched to meet the study’s goals. Moreover, references to relevant publications were examined. Finally, suitable publications were discovered and analyzed using the inclusion and exclusion criteria. 
Results: The results of Search in databases, including PubMed, Scopus, Embase, and ProQuest, showed that 12754 articles were found in the initial search. After removing duplicate and unrelated articles, finally, 155 eligible articles were selected. Based on full-text screening, 10 studies were excluded, and 5 studies were not accessible. Finally, by checking the references mentioned in the selected articles, 4 more eligible articles which were not retrieved in the search strategy were added; finally, 61 articles were selected to be reviewed. Ninteen articles were related to the general models, and 19 articles addressed job-specific assessment models. The remaining 23 articles described other existing models. 
Conclusion: To evaluate IJP, a heuristic structure was developed based on the literature research. These dimensions were selected because they can accommodate all of the preceding models’ dimensions. They also include any behaviors that may have an impact on IJP.