Showing 12 results for Heidari
F. Golbabaei, L. Heidari, S. Ghazi, K. Jabari,
Volume 4, Issue 4 (1-2015)
Abstract
Introduction: Prevention of accidents and work related diseases, are not allowed regardless of the safety of employees, customers, contractors and other persons. Assessment of individual safety management activities could reduce many losses. Present study aimed to evaluate the safety management of a household appliance manufacturing company.
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Material and Method: This study has done in a household appliance manufacturing company in Damavand city. Two questionnaires were firstly designed based on the weighted scores. The questionnaire 1 consisted of 4 indicators: Safety of machinery, Electrical safety, Risk assessment and Fire safety. Questionnaire 2 consisted of 11 sub indicators. Both questionnaires were completed by 30 HSE experts and supervisors. Reliability of questionnaires was based on cronbachs alpha coefficient. the safety status of each unit was determined and scored using information acquired by the questionnaires. Lastly, the safety of the entire company was determined.
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Result: Results showed that in safety management: the pressing and store house were in a good range of 66.66 and 60.12 points. Powder painting, enameling, laboratory were in a average range of 56.25, 55.92 and 54.15 points. Assembling and door storage were in a week range of 46.06 points.
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Conclusion: The findings showed that the safety status in the studied appliances company is in average range with 55.45 points. Therefore, it is recommended that the safety indicators should be improved for the betterment of the safety management in the company.
R. Heidarimoghadam, R. Golmohammadi, G. Roshanaei, R. Zare,
Volume 5, Issue 1 (4-2015)
Abstract
Introduction: Children have been known to spend most of their time at school. They learn their sitting habits in this period of time. Incorrect sitting postures and inappropriate school furniture can result in abnormalities in the vertebral column, back pain, neck pain, Fatigue and discomfort. Hence, this study was aimed to examine the match between students’ body dimensions and existing benches and desks dimensions in Hamadan female primary schools.
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Material and Method: In this study, 624 students of Hamadan female primary schools were investigated and some of their anthropometric dimensions including shoulder height, elbow height, knee height, popliteal height, popliteal-buttock length and hip breadth were measured. In this sense, a chair (with adjustable height, depth and elbow support) and a caliper with movable jaw were used for measurement of anthropometric dimensions. The measurements were performed in a way that thighs were in full contact with the seat, there was a right angle between the thighs and legs, the feet were in full contact with the movable pedal, the trunk was straight and the back and hips were in full contact with the backrest. Following, the match of the dimensions of existing benches and desks with the appropriate dimensions (based on the students’ anthropometric dimensions) were examined.
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Result: The results showed that the seat height, seat depth, seat width, back rest height, desk height, underneath desk height were in acceptable rangefor 10.1%, 17.3%, 5.6%, 53.5%, 1.9% and 31.1% of students, respectively.
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Conclusion: Despite differences in the body dimensions of primary school students, there is no regularity in using of school furniture. Overall, the dimensions of existing benches and desks are not matched with the anthropometric dimensions of students.
Hamid Reza Heidari, Farideh Golbabaei, Shahram Arsang Jang, Ali Akbar Shamsipour,
Volume 6, Issue 3 (9-2016)
Abstract
Introduction: Regarding development of several thermal indices and limitations of each, in this research applicability and validity of temperature- humidity index (Humidex) were examined against the standard heat index, Wet Bulb Globe Temperature -WBGT, as well as tympanic temperature of subjects.
Material and Method: This cross-sectional study was done on 163 subjects at spring and summer (2013) in outdoor jobs of arid and semi-arid climates of Iran. Environmental parameters as well as tympanic temperature of subjects were measured simultaneously and then heat indices were determined. Data were analyzed using linear correlation charts and Kappa coefficient of agreement by means of SPSS software version 20.
Result: A strong correlation was obtained between WBGT and Humidex in both arid and semi-arid regions (r>0.98), while the correlation between Humidex and tympanic temperature was moderate (r=0.5-0.8). Based on the obtained Kappa value, the agreement coefficient between Humidex and WBGT was 0.878. This value was obtained equal to 0.226 for the Humidex and tympanic temperature.
Conclusion: The results of this study showed that Humidex can be applied as an appropriate substitute for the WBGT index. However, if evaluation of environmental condition with low air temperature or very hot situation is considered, relying only on the Humidex results will not provide a realistic estimation of thermal strain imposed to individuals.
Hamidreza Heidari, Hoda Rahimifard, Abolfazl Mohammadbeigi, Farideh Golbabaei, Robabeh Sahranavard, Zahra Shokri,
Volume 8, Issue 1 (4-2018)
Abstract
Introduction: Considering the necessity of evaluating novel thermal indices for different individual and environmental conditions, the aim of this study was validation of a new enthalpy index for evaluation of heat stress in hot and dry climate.
Material and Method: In this descriptive analytical 97 city services outdoor workers were randomly selected and evaluated in spring and summer seasons in Qom city, Iran. Correlation between new enthalpy index and standard WBGT index, as well as physiological response of deep body temperature was studied and analyzed.
Result: Findings showed that regardless of the time of measurements, correlation between enthalpy and WBGT index was better than its correlation with tympanic temperature (R2= 0.756 versus R2= 0.391). Considering the time of measurement, it was found that with increasing temperature and decreasing humidity, the correlation between indices was reduced, although the correlation ratio was maintained similar.
Conclusion: Due to the simplicity of the enthalpy index measurement ,its independency to measure the globe temperature and the possibility of estimation of this index using daily climate parameters in meteorological stations, and on the other hand, appropriate validity of enthalpy against WBGT and core temperature, it can be a good alternative for WBGT index and as a screening index for thermal environments in hot and dry condition.
Ahmad Soltanzadeh, Hamidreza Heidari, Heidar Mohammad, Abolfazl Mohammadbeigi, Vali Sarsangi, Milad Darakhshan Jazari,
Volume 9, Issue 4 (12-2019)
Abstract
Introduction: The causal analysis of occupational accidents’ severity in the chemical industries may improve safety design programs in these industries. This comprehensive study was implemented to analyze the factors affecting occupational accidents’ severity in the chemical industries.
Methods and Materials: An analytical study was conducted in 22 chemical industries during 2016-2017. The study data included 41 independent factors and 872 accidents in a ten-year period (2006-2015) as a dependent variable. Feature selection algorithm and multiplied linear regression techniques were used to analyze this study.
Results: Accident severity rate mean was calculated 214.63 ± 145.12. The results of feature selection showed that 30 factors had high impacts on the severity of accidents. In addition, based on regression analysis, the severity of accidents in the chemical industries was affected by 22 individuals, organizational, HSE training, risk management, unsafe conditions and unsafe acts, as well as accident types (p<0.05).
Conclusion: The findings of this study confirmed that accidents’ severity in the chemical industry followed the multi-factorial theory. In addition, the main finding of this study indicated that the combination of features selection algorithm and multiple linear regression methods can be useful and applicable for comprehensive analysis of accidents and other HSE data.
Vahid Gharibi, Abolfazl Mohammadbeigi, Mahdi Asadi- Ghalhari, Hamidreza Heidari,
Volume 10, Issue 1 (3-2020)
Abstract
Introduction: 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.
Method: 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.
Results: 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).
Conclusion: 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
Somayeh Kamgou, Khosrou Abdi, Monire Khadem, Mahmoud Heidari, Omid Heravizadeh, Ali Daneyali, Seyed Jamaloddin Shahtaheri,
Volume 10, Issue 1 (3-2020)
Abstract
Introduction: 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.
Materials and Methods: 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.
Rashid Heidarimoghadam, Majid Motamedzadeh, Reza Kazemi,
Volume 10, Issue 2 (5-2020)
Abstract
Introduction: This paper aims to explore the main effect of night shift rotation speed on the pattern of melatonin secretion and the sleepiness, among control room operators (CORs) in a petrochemical industry
Material and method: In this study, 60 CORs operators within two different patterns, including 7 nights and 3 nights shift works were selected from a petrochemical industry to investigate the influence of rotation speed on their melatonin secretion and the sleepiness pattern. Thus, melatonin was sampled from saliva, and the sleepiness and sleep quality were assessed using Karolinska Sleepiness Scale (KSS) index. Data analysis was carried out using spss18, Chi square, t-test, and GLM model.
Results: Melatonin values and their general changes during shift were noticeably different in two proposed patterns (P <0.05). The sleepiness index was significantly different only at 3:00 in both patterns, whereas the interaction of light and caffeine on both melatonin changes and sleepiness was not significant (P <0.05). Moreover, a significant difference was observed between the process of melatonin changes and sleepiness in the two studied patterns (P <0.05).
Conclusion: Adopting slower shift schedules rotations would be more appropriate, from the viewpoints of the importance of alertness and performance for human error prevention, among people working in serious worksites such as control rooms.
Saeed Omidi, Ghorbanali Jennat Feridooni, Rabiollah Farmanbar, Mahmoud Heidari,
Volume 11, Issue 2 (6-2021)
Abstract
Introduction: Risk perception to safety and health is particularly important and affects behavior. Most of accidents occur because people do not have proper understanding about them. Accidents may be an important consequence of risk perception or, more precisely, an inaccurate perception of risk. Education has been always widely recognized as an important component of occupational risk management programs. The aim of this study was investigating the effect of an educational intervention based on the theory of planned behavior on firefighters’ risk perception in operational units.
Material and Methods: This study was a randomized controlled trial performed on 92 firefighters, in Rasht, in 2019. Cluster sampling method was carried out, and the firefighters were randomly assigned to two experimental and control groups with equal numbers. Data collection instrument was a questionnaire with the three sections including demographic variables, risk perception, theory of planned behavior constructs. The educational program consisted of five sessions of 30-75 minutes for each group (six groups of 7-8 firefighters). The data were collected before and one month after educational intervention, and analyzed by Chi-square, independent and paired-sample T test, Mann-Whitney U and Wilcoxon using SPSS software version 21.
Results: The mean age of firefighters was 35.91±5.17 years, and no significant difference was observed between the two groups in demographic variables. Before the educational intervention, no significant difference was seen between the intervention and control groups in risk perception, the model constructs and self-report behaviors, but after performing the educational intervention the variables were significantly increased in the intervention group.
Conclusion: The current study results showed an improvement in firefighters’ risk perception due to educational intervention based on the theory of planned behavior. Thus, the theory of planned behavior can be used as a theoretical framework for the design and implementation of firefighters’ risk perception.
Ali Fardi, Mohammad Karkhaneh, Hamidreza Heidari, Abolfazl Mohammadbeigi, Ahmad Soltanzadeh,
Volume 12, Issue 2 (6-2022)
Abstract
Introduction: Methane is one of the most widely used gases in industries with a high flammability potential. This study aimed to evaluate the efficiency of ventilation systems installed on methane valve pits based on hazardous areas classification.
Material and Methods: This study was implemented in a steel industry in Qom Province in 2019. The tools used in this study were a DELTA OHM pitot tube (DO-2003) to measure wind speed, EPA Protocol for equipment leak emission estimates (U.S. Environmental Protection Agency) and IEC-60079-10 for evaluating the safety of ventilation of methane valve pits.
Results: The methane LELm was about 0.0334 kg/m3, and the volume of the release area was approximately VZ = 0.053 m3. The expected leak emissions were within the Vz < 0.1 m3 range. The ventilation system embedded on methane distribution pipelines was not effective for openings with diameters of more than 0.3 mm and the volume of gas inside the valve pits would quickly exceed high ventilation border which might lead to a dangerous accumulation of gas in the valve pits.
Conclusion: Given that a very small opening or leak in gas transmission valves may lead to the formation of an explosive atmosphere, it is essential to monitor methane before entering the valve pit area and performing any operations on valve pits.
Tahereh Pourtalemi, Abdolhossein Emami Sigaroudi, Mahmoud Heidari, Nasrin Mokhtari Laleh, Ehsan Kazem Negzhad Leyli,
Volume 13, Issue 1 (3-2023)
Abstract
Introduction: Nurses are under the influence of stressful factors and high work pressure, which increases nursing errors. One factor affecting nurses’ behavior and performance is the mental workload and cognitive failures. This research has investigated the mental workload and cognitive failures in two groups of nurses with and without unsafe behaviors during the outbreak of Covid-19.
Material and Methods: This case-control study was conducted on 312 nurses during the severe period of the Covid-19 outbreak through the public hospitals in Guilan province. Sampling was performed by selecting 104 nurses in the case group (with unsafe behavior) and 208 nurses in the control group (with safe behavior) using the full count method. The data collection tool is a three-part questionnaire including demographic information, the mental workload (NASA-TLX) questionnaire, and the occupational cognitive failures questionnaire. The incidence of needle stick as a consequence of unsafe behavior was used as a criterion.
Results: The results have shown that the workload in this research was 63.96±18.26, and the total score of cognitive failures was 59.1±13.9. There was no statistically significant difference between the two groups of nurses with and without unsafe behaviors (P>0.05). Still, there was a significant correlation between the total mental workload score in all areas and the total score of cognitive failures in the group of nurses with and without unsafe behaviors (p=0.001, r=0.225).
Conclusion: According to the results, the perceived mental workload is high for the nursing job. Despite of positive correlation between mental workload and cognitive failures, it can be mentioned that there are two-way interactions through their dimensions. Therefore, the nursing job requires adopting optimal engineering and management strategies to reduce the workload.
Reza Barzegar, Omid Kalatpour, Maryam Farhadian, Rashid Heidarimoghadam,
Volume 13, Issue 4 (12-2023)
Abstract
Introduction: Industrial firefighting (IFF) constitutes a high-risk occupation within the domain of process industries. Firefighting teams serve as the operational component of the incident command team. This study aims to assess the alignment of physical fitness assessments conducted in selected Iranian process industrial firefighting settings and to scrutinize the extent of compliance with The U.S. National Fire Protection Association (NFPA) requirements by analyzing the resultant percentages of similarity in test outcomes.
Material and Methods: A cross-sectional observational study was undertaken across 14 Iranian process companies, encompassing two refinery companies and 12 petrochemical companies, employing a census sampling approach. The study’s benchmark was NFPA1582-2018. Data analysis was performed utilizing SPSS 27 software. This investigation focused on assessing the percentage of essential parallels within five distinct groups, along with their corresponding sub-components, in alignment with the tests and elements stipulated in the NFPA standard.
Results: Most of the selected companies (58%) lacked a cohesive program or established standard to assess the fitness of their firefighting personnel. Among the subset of companies (42%) that did employ an evaluation standard, in the majority of instances, a minimal proportion (less than 20%) underwent individualized assessments in line with the components outlined in NFPA 1582-2018 for physical fitness evaluation tests.
Conclusion: Given that 58% of the surveyed process companies in this study lacked a cohesive fitness assessment program and 42% demonstrated limited compliance with NFPA 1582-2018 in the assessed components, this issue underscores the critical need to evaluate the components quality and conduct a technical needs assessment. Developing adaptable and suitable components aligned with the work conditions prevalent in the process industry becomes imperative. Additionally, there must be existed a legal mandate for the pertinent ministry to implement an integrated framework. This scenario necessitates that process companies reevaluate their approaches concerning the selection and oversight of their firefighting personnel.