Journal of Health and Safety at Work

Identifying, Evaluating and Determining of The Most Important Predictive Variables of Safety Situation Awareness Using Fuzzy Logic Approach

Iraj Mohammadfam

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.

Assessment of Shoulder and Lower Back Muscles Activities of Carpet Weaver’s in the Traditional and Ergonomic Workstations Using Electromyography

Jalil Nazari

Introduction: Carpet-weaving is one of the hard and harmful jobs, which affect the health of the workforce. Based on the previously conducted research, musculoskeletal disorders in the neck, shoulder, and lower back regions are common among carpet weavers. This study conducted to investigate the muscle activity of the shoulder and lower back regions in carpet weavers during work on traditional and ergonomic workstations by surface electromyography.
Material and Methods: 18 experienced male weavers with a mean age of 38 and mean weaving experience of 11.1 years participated in this study. Each weaver took part in two trails of 120 min. Surface EMG signal recordings were done during weaving for four muscles (bilaterally in trapezius and erector spine). The RMS and MPF values were extracted from the raw EMG signal to estimate muscle activity and fatigue.
Results: The results obtained from the 5-time intervals indicated the lowered MPF in the ergonomic workstation compared to the traditional one. The result of the mean RMS in most of the recorded times was lower in the ergonomic workstation than that in the traditional one.
Conclusion: According to the results of the study, the modified workstation was well-suited for trapezius muscles, and the traditional one had an advantage for the erector spine muscles.

Evaluation of Human Errors among Nurses Using Predictive Analysis of Cognitive Errors and Human Event Analysis Techniques: Case study of the Specific Responsibilities of the Cardiac Intensive Care Unit

Sanaz Karimpour

Introduction: Considering the accreditation of international standards of hospitals and the necessity to improve the safety and quality of patients’ care, this study aimed at evaluating reliability among nurses using predictive analysis of cognitive errors and human event analysis techniques.
Material and Methods: The analysis of nurses̓ tasks was done by HTA method. Then, the types of errors and their causes were identified by TRACER method. In the next step, the error probability of each task was calculated by ATHEANA method. In order to calculate the probability of total event, the probability of human error was imported to probabilistic risk assessment.
Results: Factors affecting performance of the nurses were included: the complexity of the work, high workload, nurse’s experience, work environment design, fatigue, anxiety, shortage of the workforce, insufficient time period for doing job, sleep disturbance, and poor lighting and noise pollution. According to the instruction of ATHEANA method, the error probability for each base event was considered 0.001. Given that there are 15 base events, the probability of human error in the heart attack event was calculated 0.015.
Conclusion: The finding of this study was indicated the need for providing required nursing workforce, reducing overtime, scientific planning for nurses’ work shifts and giving practical training and stress management methods in the emergency conditions.

Investigating the Frequency and Related Factors of Needle Stick Injuries among Students of Fasa University of Medical Sciences-Fasa-2017

Majid Najafi Kalyani

Introduction: Occupational injuries are considered as the most common work-related risk factors among the medical sciences students. Medical sciences students are mostly exposed to needle stick injuries and sharp objects when training in the clinical environment due to lack of enough experience. This study aimed at investigating the frequency of these injuries and the related causes of its occurrence among the students in various disciplines of medical sciences.
Material and Methods: This descriptive cross-sectional study was performed on the students of Fasa University of Medical Sciences in 2017. All medical, nursing, operating room, anesthesiology, and medical emergencies students were recruited to this stud using census method. Then, a questionnaire was distributed among them. The data collection tool in this study was a researcher-made questionnaire consisting of two parts of demographic characteristics and the related causes of the occurrence of injuries. After completing the questionnaire by the students, data management and analysis was performed using statistical tests and SPSS 22.
Results: The results of this study showed that 74 students (24.3%) had reported being injured caused by sharp objects at least once over their studying period of time. Twenty-six students (35.1%) described their carelessness as the main cause of the injuries. Intramuscular injection with 20 cases (27%) was the most important procedure leading to needle stick exposure. Chi-square statistical test showed that there was a statistically significant difference between the frequency of injuries caused by sharp objects and gender, so that the exposure frequency was more reported by the male students (P <0.05).
Conclusion: The results showed that injuries caused by needle stick and sharp objects are high in medical sciences students. Due to this high prevalence, in educational programs, and especially in the clinical setting, accurate and precise training and arrangements are highl recommended with the emphasis on safety measures. Also, the use of personal protective equipment (PPE), before and during working with the patient is essential for medical sciences students. In addition, due to disability of injured students, making a planning program for training them about the potential risk of these injuries is necessary.

The Effect of an Educational Intervention Based on the Theory of Planned Behavior on Firefighters’ Risk Perception in Operational Units

Mahmoud Heidari

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.

Effect of Exposure to Ionizing Radiation on Biomarker of Oxidative Damage of DNA

Azam Salehi

Introduction: one of the most important complications of exposure to ionizing radiation is emergence of cancer tumors, which happens as a result of oxidative DNA. Therefore, the present study was conducted, aimed to measuring 8-DIHYDROxy- 2’- DEOXYGUANOSINE (8-OHdG) level in radiographers’ urine as oxidative damage biomarker, as well as comparing this biomarker with cumulative effective doses.
Material and Methods: In the present study, the samples were selected into two categories, 35 of whom were from different radiography groups (including nuclear medicine, radiology, radiotherapy, CT scan), and 35 subjects were from the staff, who had no exposure to radiation. The results of the film badge were gathered from the hospitals. Since film badge monitoring period was found to be 2 months, the collective effective dose was obtained according to the respective formula for 30 last period and 6 last period. Then, at the end of the work shift, the urine samples were taken to determine the 8-OHdG concentration. The samples were obtained via the SPE (solid-phase extraction) method. After that, the 8-OHdG concentration was read by the GC/MS analyzer. Finally, the data extracted from the 8-OHdG concentration and the collective effective dose of the radiation were analyzed by SPSS software.
Results: The results showed an increase in the level of 8-OHdG, as one of the oxidative biomarkers in the body of radiographers, but the level of 8-OHdG showed a direct relation in the body of the radiographers with an average collective effective dose of radiation in the last 30 as well as the last 6 periods.
Conclusion: Observing the radiation protection principles by radiation workers results in decreased radiation and, in turn, reduces the level of oxidative stress, thus, reducing the potential effects of radiation.

Evaluation of Factors Affecting Respiratory Function of Staff of Tehran University of Medical Sciences (TUMS)

Farideh Golbabaei

Introduction: The respiratory system, one of the most important organs of the body, can be affected by adverse effects, disorders and consequences in the workplace. Spirometry is one of the most important screening and testing tools in the periodic medical examination of every employee. This study was aimed to evaluate the factors affecting the respiratory function of staff of Tehran University of Medical Sciences (TUMS).
Material and Methods: This descriptive-analytical and cross-sectional study carried out on 300 employees of TUMS according on during the enrollment phase of the Tehran University of Medical Sciences employee’s cohort (TEC) study was in order to survey the parameters affecting pulmonary function. Demographic data were collected through a demographic questionnaire. Spirometry was used to evaluate respiratory function parameters and bioelectric impedance was used to analyze body composition. Data analysis was performed by SPSS software version 25. Two-sample t-test, one-way ANOVA, and Pearson correlation coefficient were used for statistical analysis. Multiple linear regression was used to determine the effect of independent variables on the parameters of pulmonary function.
Results: It was found that 73.6% of the subjects had a normal lung pattern, 7% had an obstructive pattern, 14.7% had a threatening pattern and 4.7% had a mixed pattern. There was a significant negative correlation between FVC and FEV1 parameters and smoking (P-value <0.05). There was also a significant relationship between FFM, age and BMI with FEV1/FVC (P-value <0.05). Similarly, there was a meaningful relationship between type of job and FVC parameter (P-value <0.05). The findings showed that the highest and the lowest averages of all parameters of pulmonary function was in administrative and occupational services, public and technical services and facilities, security and guard, respectively.
Conclusion: In the present study, it was found that occupation type affects lung function due to exposure to contaminants in different groups. Other factors affecting lung function included age, body mass index, fat mass, fat free mass and smoking. Therefore, changing lifestyle such as proper diet, regular exercise and not smoking can be an effective step towards improving the parameters of lung function.

Study of the Prevalence of COVID-19 Disease and Related Risk Factors in Two Groups of Industries with and without Occupational Health Management Systems

Ahmad Soltanzadeh

Introduction: Considering the importance of implementing occupational safety and health management systems for the prevention of various diseases in the workplace, as well as determining the notability and role of induction and implementation of occupational health management systems in controlling and reducing COVID-19 outbreak in work environments, as one of the most sensitive and important of society sectors, this study aimed to compare the prevalence of Covid-19 disease in two groups of industries with and without occupational health management systems and related management risk factors in several industries, in Iran.
Material and Methods: This cross-sectional study was performed in May 2020 during the outbreak of coronavirus in some industries under Shahid Beheshti University of Medical Sciences’ supervision. During the present study, 70 industries included 24 industries active in chemical products, 6 industries of automotive parts manufacturing, 14 industries of home appliance manufacturing, 16 industries of health and cosmetics products, 4 industries of metal products, and six service companies were studied. The studied population included two industries with an occupational health management system (33 industries) and industries without an occupational health management system (37 industries). In this study, a checklist was designed to collect study data based on the requirements and parameters of occupational health management systems, as well as information related to infectious diseases such as COVID-19, which included information on COVID-19 disease in two groups of studied industry, occupational medicine, biological hazards risk management, occupational health information management system, training, and employee participation, as well as the management parameters of COVID-19 outbreak. Statistical analysis of the study data was performed using the Chi-square test and Fisher’s exact test by SPSS. 23 software.
Results: The number of workers working in the two groups of industries with and without occupational health management systems was 673 and 708, respectively. Among 33 industries with occupational health management systems, 12.1% industries had health, safety, and environment management system (HSE-MS), 66.7% industries had OHSAS 18001:2007 standard, and 21.2% industries also had ISO 45001:2018 certification. It was found that the prevalence of Covid-19 disease in those industries without occupational health management systems was significantly higher (p <0.05). It has been found that Covid-19 outbreak in industries without occupational health management systems was significantly higher (p<0.05). The findings also showed that there was a significant difference between the parameters of occupational medicine, risk management of biological hazards, occupational health information management system, training and employee participation, as well as the management parameters of COVID-19 disease in the two groups of studied industries (p<0.05).
Conclusion: The findings of the present study indicated that there was a significant relationship between the scores of occupational medicine parameters and occupational health information management system, risk management of biological hazards, training and employee participation, management of COVID-19 and finally the prevalence of the disease among industries with or without occupational health management system. So, implementation and establishment of occupational health management systems can be an effective step in reducing the prevalence of viral and infectious diseases such as COVID-19.

Toluene Vapors Removal Using Cold Plasma and HZSM-5/TiO2 Photo Catalyst

Hasan Asilian Mahabadi

Introduction: Regarding the daily growth of Volatile Organic Compounds (VOCs) application in a vast variety of industries which also contributed to their adverse effects, different methods were used for controlling their emission. One of the most effective methods for this purpose, is a combination of cold plasma and catalyst or photo catalyst. In this study, the effectiveness of the HZSM-5/ Tio2 for Toluene treatment removal was investigated
Material and Methods: HZSM-5 zeolite, and Tio2 in 3 and 8 weight percent were used for photo catalyst preparation. The TiO2 particles were coated on the zeolite by impregnation method. X-Ray Diffraction, Scanning Electron Microscope and Brunauer Emmett Teller tests were used for the identification of photo catalyst structural properties. Toluene vapors with 58±2 PPM concentrations were produced in ambient condition including the room pressure and temperature by a dynamic system and introduced to a reactor included 1 gr of the photo catalyst. Vapors were passed from the reactor continuously with a rate of 0.5 liter per minute. Removal efficiency in three different states; plasma only, plasma /HZSM-5/TiO2 3%tw, and plasma/HZSM-5/TiO2 8% tw were assessed at the voltages of 4000 to 8000.
Results: In the current study, the removal efficiency of toluene vapors were 44.9, 75.36 and 66.68 percent for plasma, plasma /HZSM-5/TiO2 3%tw and plasma/HZSM-5/TiO2 8% tw, respectively. Photo catalyst with 3 weight percent showed the best removal efficiency. In all tests, the removal efficiency increased when the voltage increased and in 7000 volts it reached the maximum level. Therefore, adding photo catalyst to the plasma caused significant improvement in removal efficiency. Also, HZSM-5/TiO2 3% tw showed the best performance for toluene vapors removal.
Conclusion: According to the current study findings, using this combination in an industrial environment can be an effective way for Toluene vapors without the need for high temperatures. This combination can be proposed for other VOCs.

Investigation of Root Cause of Work-related Accidents in a Vehicle Manufacturing Company Using Tripod-Beta Method

Mousa Jabbari

Introduction: Occupational accidents are one of the major challenges of the industrial workplaces. The identifying of the effective causes of the incidents occurrence, could be used to prevent them. This study was aimed to determine basic causes of occupational accidents in a vehicle manufacturing company.
Material and Methods: The occupational accidents leading to loss of time, which cause losing at least one working day, occurred from 2012 to 2017 were analyzed using the Tripod-Beta method and the causes of their occurrences were determined from the active failures to the root causes. The data were analyzed using the SPSS-22 software.
Results: Eighty percent of the occupational accidents that occurred in a vehicle manufacturing company were related to 6 root causes, i.e. the weakness of OR (20%), EC (17%), MM¬ (12%), CO (10%), IG (10%) and DE (9%). Absence of necessary authority to stop working is the most important reason for the occurrence of the weakness of Organization system with a rate of 28%.
Conclusion: By handling three root causes appropriately, i.e. improving OR, EC and MM, more than 50% of accidents can be prevented. Proper hiring of workers, exact definition of accountability and an accurate job description to the employees, proper monitoring and supervision, and near-miss recordings are suggested to reduce this incidence rate.

Relationship between Safety Investment and Safety Performance Indices Considering the Project Hazard Level in Construction Industry

Ghazaleh Monazami Tehrani

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.

The Effect of Eight Weeks of Corrective Exercises Intervention on Reducing the Prevalence of Musculoskeletal Disorders in Computer Users of Gas Company

Sakineh Varmazyar

Introduction: Work-related musculoskeletal disorders (WMSDs) are one of the most important causes of absenteeism, increased costs and human injuries, which are very common in computer users. The purpose of this study was to investigate the effect of 8 weeks of corrective exercise on reducing the prevalence of musculoskeletal disorders (MSDs) in computer users working in a gas company.
Material and Methods: This cross-analytical study was conducted on 101 computer users working in a Gas Company in Qazvin city in 2019. Fourteen people participated in 8 weeks correction training intervention program (16 sessions in 1 hour and 2 times a week). Nordic questionnaire and body map were used in order to investigate the prevalence and severity of MSDs. The data were analyzed using Kolmogorov-Smirnov, Cramer V, McNamar, Paired sample t-test and Wilcoxon tests in SPSS version 23 software.
Results: The most common disorders were shoulder (64.3%), waist (42.9%) and neck (35.7%) regions among computer users during the last week before intervention. The prevalence of MSDsby strength and flexion exercises in neck and shoulder regions with 95% and 99% confidence showed a significant decrease before and after intervention. The incidence of discomfort in the waist region decreased by 35.8% after intervention and in other regions decreased by at least 7.1%.
Conclusion: The results of this study showed that implementation of corrective training intervention program by exercise specialists can increase muscle stretch and consequently decrease the prevalence of MSDs7.1%- 64.3%.