Journal of Health and Safety at Work

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Introduction: Shift work combined with the nature of duty in occupations such as nursing can lead to the spread of psychological consequences and disorders in nurses. The aim of this study was investigating the cognitive and psycho-social consequences associated with shift work in nurses.
Material and Methods: This study was performed in 7 hospitals in 2023. The study population was 636 nurses. Data collection tool in this study was part of a comprehensive questionnaire that translated and modified by Choobineh et al. The data were analyzed using IBM SPSS software v. 22.0, and significance level in this study was considered 0.05.
Results: Out of 636 studied nurses, 474 were shift workers and 162 were day workers. The means of age and work experience of the study population were 37.26±5.25 years and 11.60±4.78 years, respectively. The results showed that the prevalence of psychological consequences in the shift workers group was significantly more than day work nurses (p<0.05). The highest prevalence of cognitive and psycho-social consequences in shift work nurses were related to fatigue (39.66%), insomnia (36.08) and decreased sleep quality (35.44%), respectively.
Conclusion: The findings of this study indicated that the parameters of the shift work system, working hours per week, education and hospital ward are the most important factors affecting the prevalence of cognitive and psycho-social consequences and sleep disorders in the nurses. Therefore, it is suggested that a separate program should be designed and implemented for each hospital ward to control and manage the psychological consequences associated with shift work in nurses.

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Introduction: Cognitive functions play a vital role in how tasks are performed; for this, temporary cognitive and mental dysfunctions could lead to grave consequences, especially when an accurate and prompt response is required. Attention and reaction time to noise are among the most effective exogenous factors on the brain processing mechanism. This study aimed to measure the sustained attention of workers in the steel industry exposed to different sound pressure levels. 
Material and Methods: The study was conducted in 4 general stages, including 1- Selecting predictive orientation variables (age, work history, different sound pressure levels); 2- Conducting the Cognitive Performance Test (CPT); 3 Conducting N-BACK Cognitive Performance Test and 4- Modeling cognitive performance changes using model precision methods.
Results: Continuous Performance Test (CPT) results indicated that all three groups’ omission error, commission error, and response time were affected by shift time. All three components increased significantly as the shift ended, decreasing individuals’ cognitive function. Also, the higher noise impact in modeling CPT and N-Back tests indicated reduced workers’ concentration.
Conclusion: These study findings suggested that greater noise weight obtained in test modeling in three-time intervals, i.e., in the beginning, middle, and end of the shift, affected the continuous performance components of the CPT and working memory performance of the N-back test, including workers’ response time and reaction time, with workers’ rate of error increasing and their focus decreasing during the shift. 

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Introduction: The use of antineoplastic drugs in cancer treatment, while essential, poses risks due to their non-selective action on both cancerous and healthy cells. Assessing and controlling environmental contamination with these drugs in workplaces is crucial. This study aimed to evaluate the efficacy of various commercial wipes in sampling the antineoplastic drug 5-fluorouracil from surfaces to develop standardized sampling methods.
Material and Methods: This study assessed the efficiency of commonly used commercial wipes (Whatman cellulose filter, cotton swab, Millipore™ filter, sterile gauze pad, and alcohol pad) for sampling 5-fluorouracil from different surfaces (stainless steel, vinyl, and ceramic). The sampling area was defined using disposable cardboard frames, and 1000 microliters of a 1 µg/mL 5-fluorouracil solution were applied to each surface. Sampling and extraction were conducted following NIOSH guidelines. The frame dimensions were 10 × 10 cm, limiting the sampling area to 100 square centimeters. Analysis was performed using high-performance liquid chromatography (HPLC), and results were analyzed using Prism GraphPad software, version 8.
Results: The sampling efficiency varied across wipes and surfaces, ranging from 11.2% to 86.2%. Alcohol pads showed the highest efficiency on stainless steel surfaces, while the Millipore™ filter had the lowest efficiency across all surfaces. Extraction efficiency ranged from 43.8% to 98.8%, with alcohol pads providing the highest recovery. Sample stability was maintained over 15 days.
Conclusion: Alcohol pads were most effective in collecting and extracting 5-fluorouracil, particularly from hard, smooth surfaces such as stainless steel and ceramic. These findings may improve sampling methods, thereby reducing occupational exposure to antineoplastic drugs. Further research on different wipes and extraction parameters could refine drug analysis techniques. 

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Introduction: Nowadays, the statistics prove that the underground construction projects in the country are increasing, as well as the number of accidents arising from the unsafe condition of these projects. The purpose of this study was to create a framework of safety and health risk management in the construction phase of the Tehran Metro Line 7 tunnel, using IoT technology.
Material and Methods: In the first stage, the national safety and health standards, laws and requirements related to the mentioned hazards were collected. In the second stage, the criteria and permissible limits of exposure to occupational hazards were determined. Next, sensors with optical, auditory, gas detection, and visual capabilities connected to the network were examined, and computer programming and comparing sensor information with the specified standards were carried out. Finally, intelligent warning and control systems related to the determined hazards were proposed.
Results: In this study, a combined model of risk management utilizing IoT for controlling and monitoring safety and health hazards such as sound, light, explosive and toxic gases was proposed. According to the model, sensors for detecting the mentioned hazards were determined and coded based on the permissible limit of each of the harmful factors.
Conclusion: This study has shown that by employing specialized IT and safety knowledge and utilizing relevant software and hardware, the concept of the Internet of Things can be utilized in precise monitoring of the concentration levels of flammable and toxic gases, as well as monitoring of physical agents such as noise and light in various workplace, such as metro tunnel construction sites.

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Introduction: Microperforated panels (MPPs), often considered as potential replacements for fiber absorbers, have a significant limitation in their absorption bandwidth, particularly around the natural frequency. This study aims to address this challenge by focusing on the optimization and modeling of sound absorption in a manufactured MPP.
Material and Methods: The study employed Response Surface Methodology (RSM) with a Central Composite Design (CCD) approach using Design Expert software to determine the average normal absorption coefficient within the frequency range of 125 to 2500 Hz. Numerical simulations using the Finite Element Method (FEM) were conducted to validate the RSM findings. An MPP absorber was then designed, manufactured, and evaluated for its normal absorption coefficient using an impedance tube. Additionally, a theoretical Equivalent Circuit Model (ECM) was utilized to predict the normal absorption coefficient for the manufactured MPP.
Results: The optimization process revealed that setting the hole diameter to 0.3 mm, the percentage of perforation to 2.5%, and the air cavity depth behind the panel to 25 mm resulted in maximum absorption within the specified frequency range. Under these optimized conditions, the average absorption coefficient closely aligned with the predictions generated by RSM across numerical, theoretical, and laboratory assessments, demonstrating a 13.8% improvement compared to non-optimized MPPs.
Conclusion: This study demonstrates the effectiveness of using RSM to optimize the parameters affecting MPP performance. The substantial correlation between the FEM numerical model, ECM theory model, and impedance tube results positions these models as both cost-effective and reliable alternatives to conventional laboratory methods. The consistency of these models with the experimental outcomes validates their potential for practical applications.

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Introduction: The safety harness is a critical device for preventing falls from height, particularly in the construction industry. This study aimed to identify the factors contributing to the non-use of safety harnesses during work at height and to evaluate the comfort, satisfaction, and usability of these harnesses among construction workers in Tehran using a custom-designed tool.
Material and Methods: A semi-structured interview was conducted with construction workers to identify the factors influencing the non-use of safety harnesses. The collected data were analyzed using MAXQDA 10 software. Based on the results, which revealed dissatisfaction with the current safety harnesses, the levels of comfort, satisfaction, and usability were assessed using the Safety Harness Usability and Comfort Assessment Tool (SHUCAT) questionnaire.
Results: The reasons for not using safety harnesses were categorized into four main groups: management factors, worker attitudes, comfort, and harness design. These were further subdivided into 27 subgroups. The average satisfaction and comfort scores for safety harnesses were 26.8 ± 6.25, indicating that workers generally felt uncomfortable and dissatisfied with their harnesses. The average usability score was 38.70 ± 5.60, reflecting poor usability of the harnesses.
Conclusion: Improving the safety harness design could enhance workers’ comfort and satisfaction, increasing their willingness to use the equipment. Incorporating feedback from users and experts into the design process can help address the identified shortcomings and result in better product development.

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Introduction: Exposure to various chemicals can occur in the workplace. Polycyclic aromatic hydrocarbons (PAHs) are among these compounds. The aim of this study was to investigate the relationship between exposure to PAHs and urinary metabolites among built-up roofing installers.
Material and Methods: The current case-control study, conducted in 2021 in Ilam City, involved 35 built-up roofing workers as the case group and 15 non-exposed workers as the control group. In this study, in addition to the workers’ respiratory area, samples were taken from the urine to determine the amount of PAHs metabolites. HPLC was used to analyze the samples. The collected data were analyzed using SPSS software version 22.
Results: The mean concentrations of PAHs including naphthalene, phenanthrene, fluorne, pyrene, benzo(a)pyrene, benzo (ghi)perylene and indeno 1,2,3 cd pyrene were 440.26±80.07, 70.49±24.36, 15.18±5.98, 31.21±10.36, 2.15±1.41, 2.25±0.07 and 1.18±0.06 ng/m3, respectively, in respiratory area of the workers. Also, the average level of compounds 1- naphthol, 2- naphthol, 2-hydroxyfluorene, 3-hydroxyfluorne, 1-hydroxyfenanterol, 2+3-hydroxyfenanterol and 1- hydroxypyrene, present in the urine of the population, was obtained equal to 2±1.02, 6.03±2.5, 0.18±0.15, 0.14±0.1, 0.19±0.08, 0.04±0.02 and 0.34±0.26 μg/g creatinine, respectively. Statistical test showed that the values of these compounds were significantly different in the two groups (p <0.05).
Conclusion: Estimating the concentration of aromatic hydrocarbons in the respiratory area of built-up roofing workers showed the noticeable exposure to these compounds, although lower than the allowable limits. However, due to the high carcinogenic nature of these compounds, it is recommended to use appropriate personal protective equipment such as respirators and appropriate work outfits in addition to the technical strategies to combat the exposure.
 

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Introduction: Domino effects are a chain of low-probability and high-consequence accidents in which a primary event (fire or explosion) in one unit causes secondary events in adjacent units. Bayesian networks have been used to model the propagation patterns of domino effects and to estimate the probability of these effects at different levels. The unique modeling and flexible structure provided by Bayesian networks allow the analysis of domino effects through a probabilistic framework, taking synergistic effects into account.
Material and Methods: Firstly, collecting the basic information related to the location of the storage tanks and determining the scenario of the accidents were done. Furthermore, the values of the heat radiation as escalation vectors in case of a fire in one tank were determined using ALOHA software. The received heat flux values were compared with the heat radiation threshold of 15  kw/m² and the escalation probability of the primary unit and the propagation of the initial scenario to nearby storage tanks were determined using Bayesian networks.
Results: The analysis of the heat flux values showed that among the 8 studied storage tanks, two storage tanks had the highest potential for spreading domino effects due to their location in a tank farm. Also, the implementation of Bayesian networks in GeNIe revealed that, compared to other storage tanks, the probability of domino effects propagating to other nodes is higher when a primary fire accident occurs in the two mentioned tanks, while considered as primary units.
Conclusion: Domino effect modeling and appropriate preventative measures can decrease the escalation probability in the process industries. Consideration of the synergistic effects of events at different levels by taking the escalation vectors into account leads to proper risk management and the determination of emergency response measures in storage tank farms.

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Introduction: In all societies, tools and equipment are generally designed for right-handed people, who make up approximately 90% of the population, but left-handed and ambidextrous people (those who use both hands in manual activities) also live among us. Even in delicate and sensitive jobs. This research investigated the relationship between the spectral effect of the dominant hand and grip strength and hand dexterity.
Material and Methods: A cross-sectional study was designed to measure the power and precision grip of 182 adult participants (56% female and 44% male). The dominant hand of the participants was determined using the Edinburgh Dominant Hand Questionnaire. Power grip strength was measured using the Constant 14192-709E. Pinch grip test was performed using Saehan Hydraulic Pinch Gauge SH5005 for both hands separately. Dexterity of both hands was also measured using the Pegboard 32020A tool.
Results: Power and precision grips were more common in men than in women (P<0.001). Power grip differed between right- and left-handed women (P=0.019), with right-handed women having greater grip strength. The Precision grip of left-handed men was significantly (P<0.001) greater than that of right-handed men. Hand dexterity of left-handed men was significantly (P<0.001) higher than that of right-handed men. Two-handed agility (P<0.001) and assembly dexterity (P<0.001) are significantly higher in ambidextrous people than in right- and left-handed people.
Conclusion: The power, precision grip and dexterity are different between women and men. The grip strength of men is stronger than that of women. Ambidextrous people have more dexterity and assembly agility, so in jobs that require the use of two hands, they perform better and will be recommended for employment in this category of jobs. 

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Introduction: Fire safety in healthcare centers is crucial due to the limited evacuation capacity of the occupants and the necessity of not disrupting the operation in these centers. In this study, the fire risk of a public hospital was evaluated using the Fire Risk Assessment Method for Engineering (FRAME). Additionally, the factors affecting fire safety in the hospital were analyzed quantitavely, and fire control strategies were presented. 
Material and Methods: First, the fire risk assessment checklist was filled in all the hospital departments. Then, the values of the factors affecting fire safety were obtained. In the next step, the fire risk for the building, occupants and activities were estimated using Excel software-FRAME. Finally, control strategies and intervention measures were presented based on the value of these factors. 
Results: In the hospital under study, 22% of the departments posed an undesirable fire risk to the building and its property. On the other hand, 90% of the departments had risk levels that were undesirable for the occupants. The results of the initial risk (R0) showed that a balance between potential fire risk and risk acceptance can be established by implementing manual fire extinguishing systems and automatic detectors in all departments. 
Conclusion: ased on the condition of the hospital studied, a balance between potential fire risk level and risk acceptance level was not established. Therefore, there is a need for fire control measures, especially fire safety measures for the occupants. The results of this study can be useful for readers and experts in interpreting fire risk assessments and presenting detailed control measures based on the risk assessment and the value of the parameters.

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Introduction: Sugarcane is an important and strategic product in many countries, including Iran. While the introduction of mechanization, e.g., sugarcane harvesting machines, has significantly enhanced the production process, operators of these machines still face many ergonomic and safety challenges. 
Material and Methods: The present study investigated the ergonomic status of sugarcane harvester operators by examining some of their physiological and physical evaluations. Physiological evaluations included heart rate, oral temperature, and energy consumption of the operators, perceptual strain index, and physiological strain index. Physical evaluation included estimating the amount of pain and discomfort in body segments. The correlation between pain and discomfort of body parts with some demographic and physiological indices of users was investigated using IBM SPSS 24 software.
Results: Sugarcane harvester operators’ heart rate, energy consumption, and physiological strain index were 79.05 beats/min, 18.81 kJ/min, and 0.83, respectively. The average of three indices of thermal sensation, perceived exertion of activity, and perceptual strain index were estimated as 4.40, 9.21, and 8.86, respectively.
Conclusion: Pain and discomfort in the neck and back segments, like many agricultural activities, had the highest rate among the body parts. Also, shorter and thinner operators reported higher pain and discomfort in some segments of the body. 
 

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Introduction: Safety in process industries is of paramount importance, as these industries typically deal with hazardous chemicals and complex processes that can lead to irreparable consequences in the event of accidents. The present study aims to evaluate domino effects and analyze the vulnerability of storage tanks using graph theory and Bayesian networks in a process industry. This approach can help identify system vulnerabilities and facilitate the prediction of potential accidents, ultimately leading to improved safety measures.
Material and Methods: In this study, after collecting initial information related to the location of storage tanks and determining accident scenarios, the tanks under investigation were selected based on the type of stored materials and their layout, with input from experts. These tanks were modeled as nodes in a graph, and the probability of accident spreading among them was represented as edges in the graph based on the amount of heat radiation. Additionally, for modeling domino effects and analyzing vulnerability, graph theory and Bayesian networks were employed.
Results: Based on the target tanks related to the pool fire scenario, domino effects in the tanks were identified and modeled as a theory graph. Tank number 4 was determined to be the most influential and susceptible tank in the spread and initiation of domino effects, with the highest betweenness index (0.2381), outcloseness index (0.35211), and incloseness index (0.3663). Additionally, based on the allcloseness index, the most likely sequence of the tank involvement in fires caused by domino effects was identified.
Conclusion: In order to reduce the likelihood of exacerbating domino effects, modeling the effects using Bayesian networks and graph theory is proposed; the results can also be applied to optimize fire suppression strategies. Additionally, vulnerability analysis through graph theory and the assessment of tanks regarding their potential for fire initiation and spread can be beneficial in managing the risks associated with domino effects.

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Introduction: Biomechanical risk factors, including wrist and elbow angle and standing and sitting position, are the primary factors affecting hand grip strength and perceived exertion. The interaction of these factors can include different effects on grip strength and perceived exertion. Therefore, the present study examines the interaction of varying wrist and elbow angles in sitting and standing postures on the variability of grip strength and perceived exertion.
Material and Methods: In the present study, 30 students (15 females, 15 males) aged 19-30 participated. The average grip strength was measured by a dynamometer for 12 different positions based on the angle of the wrist and elbow in both standing and sitting postures. Perceived exertion was also assessed using the Borg CR-10 scale for each setting. Data analysis was performed using SPSS 23. The Wilcoxon test was applied to compare perceived exertion between standing and sitting postures. Furthermore, a three-way ANOVA was performed to examine interactions between posture (standing/sitting), elbow, and wrist angles. Mauchly’s Sphericity Test was applied to confirm the ANOVA assumptions, and effect sizes for multivariate analysis were calculated (partial η2).
Results: In both sitting and standing postures, the highest average grip strength was observed at a 0-degree wrist angle with a 90-degree elbow angle (standing: 28.6 ± 10.8, sitting 25.8 ± 9.8), while the lowest average grip strength was recorded at full wrist extension with a 0-degree elbow angle (standing: 19.3 ± 6.5, sitting 17.9 ± 6.9). In all three elbow angles examined (0°, 60°, and 90°), the highest value of perceived exertion was recorded in the full extension of the wrist. The changes in the grip strength at different angles were the same for sitting and standing postures, yet the hand grip strength was higher in the standing than the sitting posture (P-value<0.001). The effect of each of the studied factors (sitting and standing postures, wrist angle, and elbow angle) alone on hand grip strength and perceived exertion was deemed to be significant (P-value<0.001). Regarding the two-way interactions of the research variables, the interaction effect of elbow and wrist angles on grip strength (partial η2=0.09, P-value=0.015) and perceived exertion was significant (partial η2=0.08, P-value=0.06). Furthermore, findings indicated that the wrist angle had a more pronounced effect on the value of the perceived exertion (partial η2=0.31, P-value<0.001).

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Introduction: Micro-perforated panel (MPP) absorbers are emerging as next-generation absorbers due to their considerable advantages. However, their main drawback compared to other absorbers is their limited bandwidth. This study aims to investigate methods for enhancing the bandwidth of an MPP in the frequency range of 1 to 1500 Hz through simulation using the Finite Element Analysis (FEA) in COMSOL software.
Material and Methods: The modeling was conducted using FEA in COMSOL version 5.3a. To increase the bandwidth, techniques such as series-parallel configurations, symmetrical and asymmetrical air gap depths, and the incorporation of two porous absorbing materials in symmetric and asymmetric air gap layers were employed. In the initial phase, the best configuration was selected and retained for the subsequent stages.
Results: The optimal arrangement involved two upper MPPs having larger holes and a lower perforation percentage compared to the two lower MPPs. It was also found that increasing the depth difference between the air layers of the upper and lower MPPs led to a greater increase in bandwidth than when they were closer together. Furthermore, the use of fibrous porous materials in one of the layers resulted in a reduction of resonance peak while enhancing the bandwidth.
Conclusion: MPP absorbers exhibit diverse behaviors due to their Helmholtz structure and parametric design. If their constituent parameters are tailored to match the acoustic characteristics of the target sound, they achieve optimal efficiency. Additionally, employing numerical methods such as FEA serves as a suitable alternative to more costly laboratory methods.

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Introduction: Despite advancements in road safety and vehicle design, road accidents remain prevalent, a quarter of which are caused by driver distraction. This issue is particularly critical in the public transport sector, especially among urban bus drivers, as distraction can lead to serious injuries and fatalities. Accordingly, this study explored the factors influencing distraction among urban bus drivers through a qualitative approach and a macroergonomics perspective.
Material and Methods: In this study conducted in 2024 in Tehran, 18 urban bus drivers were selected through cluster sampling. The participants included 10 drivers from bus rapid transit (BRT) system and 8 drivers from non-BRT services. Data were collected through semi-structured interviews with the drivers as well as on-site observations. Subsequently, a directed qualitative content analysis approach, based on the balance theory model, was used to analyze the collected data.
Results: The findings revealed that the primary sources of distraction belonged to six levels of the work system, the most cited of which were environment, tasks, and organization. Specifically, inappropriate behavior of other street users as an environmental factor and the driver’s interactions with passengers as task-related factors were identified as key sources. Additionally, organizational factors such as interactions with supervisors and colleagues, as well as salary issues, were significantly important. The participants very limitedly expressed using mobile phone while driving as a main distractor to their driving.
Conclusion: The current study identified various influential factors, spanning different levels of the work system, affecting bus drivers’ distraction, including generic factors that impact all urban drivers and specific factors that uniquely affect bus drivers. Addressing these factors through providing appropriate education for both passengers and street users along with implementing management strategies in the organization to enhance intra-organizational relationships and organizational support can lead to the safety of the bus drivers.
 

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Introduction: Volatile organic compounds (VOCs) are hazardous toxic pollutants in the air, which are released from various industrial sources. Due to the adverse effects of xylene on health, the effective removal of VOCs from the air by nano sorbents is crucial. In this study, nanographene (NG) and nanographene oxide (NGO) were used as adsorbents to investigate the efficiency of xylene removal.
Material and Methods: In this study, in order to investigate the absorption efficiency of nanographene and nanographene oxide after the synthesis of nano absorbents in a dynamic system, xylene vapor was produced in a chamber in pure air and stored in a Tedlar sampling bag and then transferred to the adsorbent. Subsequently, the effect of various parameters such as xylene concentration, inlet air flow rate, and absorbent mass values at 32% humidity and 25°C temperature on the absorption rate and performance of the desired absorbents was investigated. Finally, the gas chromatographic flame ion detector (GC-FID) determined the concentration of xylene in air after the adsorption-desorption process.
Results: The average adsorption efficiencies for NG and NGO were found to be 96.8% and 17.5%, respectively. The characteristics of the NG and NGO adsorbents indicated that the particle size range was less than 100 nanometers.
Conclusion: The results demonstrated that the adsorption efficiency of NG for the removal of xylene from the air is higher than that of NGO. The GC-MS method validated the proposed approach in real air samples.

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Introduction: This study aimed to analyze the effects of endurance training (Aerobic) on the levels of inflammatory markers (IL-6/TNF-α) and some metabolic parameters in male rats with non-alcoholic fatty liver disease to investigate the feasibility of using exercise training to reduce inflammation.
Material and Methods: A total of 44 Wistar rats were randomly assigned into two groups: (I) standard diet group of 22 rats and (II) high-fat diet group with 22 rats supplemented with free access to fructose water. After 17 weeks, two rats from each group were sacrificed, and liver tissue was collected for hematoxylin-eosin staining. Subsequently, the remaining 20 rats in the (I) group were divided into a training group (T) and a control group (C). The 20 rats in the (II) group supplemented with fructose water were divided into a fatty liver group (FL) and a fatty liver + training group (FL+T), each comprising ten rats. In the next phase, the T-groups underwent an eight-week endurance training intervention. Then, IL-6, TNF-α, glucose, insulin, insulin resistance and sensitivity levels were measured.
Results: The results of the present study showed that as a result of a high-fat diet with liquid fructose in HFD+HF group rats, non-alcoholic fatty liver disease (NAFLD) with complications such as a significant increase in the levels of IL-6 and TNF-α, Hepatic dysfunction, and metabolic parameters were disturbed (p<0.001). However, endurance training improved most of these complications by reversing the disease process (p<0.001).
Conclusion: According to the results of the present study, it can be concluded that the improvement of inflammatory markers, liver dysfunction, and metabolic parameters through endurance training is one of the key mechanisms of exercise in the treatment of NAFLD, the consequences of which may show the importance of endurance training in treatment of NAFLD highlights.

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Introduction: The increasing advancement of technology in the field of digital technology and automation has led to a change in the line of work and job content, and it seems that organizations are pushing their employees towards harder and longer work, which affects the health of employees. This study investigated the impact of job demands and resources on overtime and work-related health through the mediation of workaholism and work engagement.
Material and Methods: The work is a descriptive survey in terms of purpose and nature. The study’s statistical population consisted of employees of Isfahan Metro Company (320 people), of which (175 people) were studied by Simple Random Sampling. To collect the required information, Spence and Robbin’s (1992) Addiction Questionnaire, Lodahl and Kejner’s (1965), Langseth-Eide’s (2019) Perceived Health-Related Questionnaire, and Bryson Bangers’ Caricature Content (1998) were distributed and supplemented based on a Likert scale. A Structural equation model (SEM) was used to test the hypotheses.
Results: The results showed that job demands on workaholism (β=0.394, T=5.969, P <0.05) and job resources had a positive and significant relationship with work engagement (β =0.502, T =7.832, p <0.05), and workaholism and work engagement on the relationship between job demands and resources over time and health. Mediating work-related perceptions (Z= 4.383, Z= 2.189, Z= 3.797). In addition, job resources did not moderate the relationship between job demands and workaholism (β= -0.049, T =1.333, p> 0.05). 
Conclusion: The results of this study showed that there is a distinction between workaholism and work engagement as two different types of hard work (i.e., negative and positive) in the health process in the JD-R model. 

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Introduction: Operating room personnel are involved with occupational physical activities such as repetitive bending, holding surgical tools and standing for long hours that can lead to musculoskeletal disorders (MSDs). Low back pain (LBP) is the most prevalent and costly problem among these disorders. The aim of this study was to determine the relationship between occupational physical activity, LBP and disability among operating room personnel.
Material and Methods: A total of 60 operating room personnel voluntarily participated in the study, all of which had at least two years of working experience. At the end of a working week, the degree of disability and pain were assessed by Graded Chronic Pain (GCP) questionnaire. The International Physical Activity Questionnaire (IPAQ) was used to evaluate the level of physical activity. Simple linear regression was conducted to investigate the relationship between physical activity, LBP and disability. 
Results: The survey using the GCP questionnaire revealed that 58.3% of participants reported experiencing occupational back pain, while 41.7% reported no back pain.  Among those with back pain, the average pain intensity was rated 43.11 (18.22) on the scale.  Pain remained stable for an average of 2.3 days (standard deviation = 0.95).  The average level of disability associated with back pain was 32.09 (27.44). Statistical analysis using simple linear regression showed a significant relationship between back pain and several factors: vigorous physical activity (p-value = 0.02), prolonged sitting time (p-value = 0.01), and chronic pain (p-value < 0.001).
Conclusion: Occupational physical activity characterized by low intensity, but high repetition and standing for a long time in fixed postures were the most significant contributors to lumbar back pain among operating room personnel. Chronic pain in this population was reported as grade 2, indicating severe pain with minimal disability; if left unaddressed, this could lead to movement restrictions.

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Material and method:  In this study, industrial accidents during gas pipeline excavation and piping operation were analyzed using Bowtie method. The Fuzzy DEMATEL method was used to determine relationships between accident root causes, and the Fuzzy AHP method was used to compare pairs of causes and determine their weight. Finally, Bowtie and DEMATEL outputs were mapped in Bayesian networks and important risk factors of accident were determined.
Introduction: Identifying and modeling the root causes of accidents can play an important role in preventing them. The purpose of this study is to identify and model the causes of gas pipeline excavation and piping operation accidents using Bayesian network (BN) and fuzzy DEMATEL.
Results: The most important risk factors for trench collapse accident were risk management (16% impact weight), competency assessment (14.2% impact weight), supervision (13.8% impact weight), work permit system (13.7% impact weight), compliance with requirements and guidelines (13.4% impact weight), training (11.4% impact weight), HSE system (9.5% impact weight) and contractor management (8%impact weight).
Conclusion: From the results obtained in this study, it can be said that the risk management and competency assessment with a higher weight percentage play a more important role in the occurrence of trench collapse accident. The results of this study can be used to prioritize corrective actions to prevent trench collapse accidents in gas pipeline excavation and piping operations.