مجله بهداشت و ایمنی کار
سال سیزدهم شماره 4 (زمستان 1402)

Medical centers, as complex technical-social systems, are exposed to the risk of fire incidents. This study analyzes the causes and contributing factors of the fire accident at Sina Mehr Clinic to prevent similar accidents, resulting in 19 deaths and 14 injuries.

The causes and contributing factors for accidents in medical centers are found through studies related to laws and regulations, official accident reports, expert reports of regulatory bodies, interviews with experts, and review of past studies, extraction, and categorization. Accident analysis methods included AcciMap and STAMP. Finally, experts’ opinions were used to confirm and strengthen the findings.

The most critical root and hierarchical causes of the weakness of medical center management in the field of safety, dangerous conditions, fire accidents, and emergency response are the issuance of a legal building completion permit for a building that violates national building regulations and the issuance of a legal permit for a medical institution for a building with residential use, as well as the insufficiency of supervision by government and public institutions with horizontal relationships with each other and vertical relationships with universities of medical sciences, labor offices, and firefighting organizations, as the direct supervisors of medical centers.

The AcciMap and STAMP findings indicate that the priority is to amend the regulations for the establishment, operation, and activity of medical centers with an emphasis on safety regulations, as well as the frequency and shortening of feedback loops such as inquiring about the building completion permit from the municipality, announcing the establishment of a medical center to other governmental and public supervisory authorities, and the reporting of unsafe cases directly by supervisors to the Ministry of Health. Legal authorities are the most crucial cycle in the resilience of fire incidents and their consequences in medical centers.

Musculoskeletal disorders (MSDs) have a multifactorial nature. Biomechanical factors are one of the most important factors. Consequently, the precise identification of effective factors plays a significant role in controlling and preventing these disorders. Therefore, the current study aimed to identify the awkward upper body postures and their effect on the prevalence of MSDs in office workers in both women and men groups by objective methods.

In this cross-sectional study, the participants were 36 office workers (18 women and 18 men). The prevalence of musculoskeletal discomfort was evaluated using the Nordic questionnaire. The upper limbs posture, including the back, neck, and wrists, was evaluated continuously with an electronic inclinometer and an electrogoniometer for 30 min, followed by analyzing the collected data.

The results revealed that the highest prevalence of musculoskeletal symptoms in both gender groups was in the neck (58.33%), trunk (52.77%), and wrist (47.22%), respectively. The results disclosed that the median trunk and neck flexion in both groups is over 20° and the posture angle in women is higher than that of men (P<0.05). The results showed that pain and discomfort in the trunk and neck in both gender groups have a significant relationship with the median posture angle (P<0.05). Also, the wrist posture in both gender groups during work was in extension and static condition.

Based on the results of this study, the prevalence of disorders in women was higher than in men. Although the tasks performed in both groups were similar, the assessment of postures disclosed that women office workers had more awkward postures in the trunk and neck than men. In both groups, the prevalence of musculoskeletal discomfort had a significant relationship with awkward postures in the trunk and neck. According to the results of the current study, ergonomic interventions are recommended to reduce awkward postures and to prevent MSDs, particularly among women office workers.

Despite the legal prohibition of asbestos fiber usage in the country, numerous studies have documented its presence in the air of various cities, including Tehran. This urban air pollution stems from the extensive use of asbestos in construction materials such as pipes, insulators in cooling and heating systems, and friction devices like brake pads and clutch plates, among other consumer products. Prolonged exposure to these fibers can have severe health consequences for residents, leading to respiratory issues, pulmonary fibrosis, and cancers such as mesothelioma. Consequently, we conducted a descriptive cross-sectional study to examine both the extent and nature of asbestos fiber distribution in Tehran’s air.

This study measured the concentration of asbestos fibers in Tehran’s air over a 12-month period. Monthly samplings were conducted at eleven Tehran Air Quality Control Company-operated stations. The sample collection, preparation, and analysis adhered to the NIOSH 7400 method. Microscopic examination results were then translated into asbestos fiber concentrations using the appropriate formulas.

Analysis of samples taken across four seasons revealed that spring recorded the highest average asbestos fiber concentration at 0.00134 f/ml, while the lowest concentration was observed in summer at 0.117 f/ml.

Given the widespread ban on asbestos use in many countries, including Iran, its presence in urban air is unexpected. Regrettably, flawed policy decisions made during the import ban announcement and the extended timeframe set for the ban’s initiation allowed companies to import and stockpile asbestos indiscriminately for future use.

Work-related musculoskeletal disorders (WMSDs) are a prevalent occupational health concern, influenced by both physical and psychosocial factors. Valid questionnaires offer a cost-effective and efficient means of evaluating WMSDs. This study aimed to validate the Persian version of the MDRF questionnaire, assess its applicability in Iran, and investigate the prevalence of WMSDs among employees in an automotive industry.

This descriptive cross-sectional study was conducted among 100 employees (50 production line workers and 50 office workers) in Kerman province. The linguistic validity of the questionnaire and its translation were ensured using the Backward-Forward method. Content validity was assessed through CVI and CVR indexes. To evaluate the questionnaire’s reliability and agreement, Cronbach’s alpha and ICC were employed. User responses from the first and second series of the questionnaires were validated using Kappa and Spearman’s tests.

Results indicated high reliability which was achieved by Cronbach’s alpha and ICC values of 0.960 and 0.925, respectively. The questionnaire’s validity was acceptable based on CVR and CVI tests. The prevalence of WMSDs was the highest in the lower back for both production line and office workers over the past year. The job satisfaction factor exhibited the highest risk level among the questionnaire’s four subgroups. Approximately 85% of participants were classified as having a high or very high-risk level, reflecting concerning conditions among the employees. The prevalence of WMSDs in different body parts significantly correlated with all physical and psychosocial stress factors.

This research highlights the influence of diverse physical and psychosocial risk factors on the occurrence of WMSDs among both occupational workers and office employees. Also, the MDRF questionnaire, whose high applicability in assessing the WMSDs risk factors was proven in this study, is an effective tool for prioritizing, planning, and executing educational and preventive measures within the workforce community to mitigate and prevent WMSDs.

To ensure employee safety and health, it is crucial to choose and use personal protective equipment correctly. An investigation of the respiratory and hearing protection equipment used in the industries of Tehran was conducted in the present study.

This study was a descriptive-analytical study conducted in 2023 on 400 occupational health and safety experts in Tehran province. A researcher-made checklist and questionnaire (physical and online versions) were used to determine the criteria that are considered when selecting protective equipment. Statistical analysis and graphing were performed using SPSS-v21 and Excel-2016.

Participants had an average age of 38.66 and an average work experience of 11.78 years. The participants reported 48.3% and 47.7% disapproval of the quality and 42.5% and 39.5% disapproval respectively of the quantity of respiratory and hearing protection equipment available in their industrial units. In addition, 56.3% of them admitted that they have no responsibility for providing or approving the equipment in their workplace. Overall, 27 and 29 criteria were mentioned by study participants pertaining to respiratory and hearing protection equipment, respectively. In the identified criteria, the frequency distribution ranged from 0.3% to 38%.

A high rate of expert dissatisfaction with protective equipment and a low frequency of most of the criteria mentioned indicates that industries aren’t paying much attention to the issue of choosing the right respiratory and hearing protection equipment. To improve the situation, more investigation is needed and practical and operational solutions will be provided. This study highlights the importance of proper selection and use of personal protective equipment in ensuring the safety and health of employees.

Due to the lack of an instrument for measuring the career issues of those with bipolar disorder, the present study was conducted to develop and examine the psychometric characteristics of the Career Issues Inventory for Persons with Bipolar Disorder (CII-BD).

To check the diagnostic validity, via purposive sampling and interviews by a psychiatrist, 108 people were selected from two sample groups (53 normal people and 55 participants with bipolar disorder). The items were extracted from three sources including scientific articles related to the career issues of bipolar people, interviews with individuals with bipolar disorder, and interviews with experts using the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) systematic qualitative method. Finally, the items of the CII-BD were reduced to 81 questions. Content, construct, and convergent validity plus factor analysis of CII-BD were also examined. The reliability of CII-BD was evaluated by internal consistency and test-retest method with seven weeks intervals after the initial implementation of the CII-BD.

The convergent validity of the sum score of CII-BD with the sum score of the symptom inventory of people with bipolar disorder among the sample of normal people and the sample of persons with bipolar disorder was (r=0.79, P<0.01, N=53) and (r=0.78, P<0.0001, N=53) respectively. In construct validity examination, nine subscales were extracted using the factor analysis method with varimax rotation, which included communication problems, poor work performance, insecurity, grandiosity, unreliability, change-seeking, vulnerability, lack of boundaries, and lack of self-control towards the opposite sex. In the reliability analysis, Cronbach’s alpha coefficient was 0.96 (N=55, participants with bipolar disorder) and 0.86 (N=53, normal people), respectively, P<0.05, showing the high internal consistency of CII-BD. The test-retest correlation coefficient of the sum scores of the CII-BD was r = 0.91, P < 0.01, which indicated the credible stability of the CII-BD.

The CII-BD is a valid and reliable instrument to measure the specific career issues of bipolar persons and their early vocational rehabilitation. It is suggested that future research should focus on choosing a job and job placement for bipolar disorder persons.

The COVID-19 pandemic has been a significant global health challenge. Primary care services, such as screening health centers, were crucial in identifying infected individuals. However, these centers were often crowded and posed a high risk to staff and non-COVID-19 patients. This study aims to assess the risk of airborne transmission of SARS-CoV-2 in such settings through simulation.

In this study, waiting and sampling rooms of a COVID-19 healthcare center were simulated using different scenarios. Then, the Quanta emission rate was estimated using the viral load in the sputum of infected individuals. Finally, the airborne transmission risk of SARS-CoV-2 was determined using the Wells-Riley method for scenarios of wearing and without masks.

The study showed that the Quanta emission rate in an unmodulated speaking activity was higher than other expiratory activities in both units (p <0.001). Also, the total amount of Quanta was slightly higher in the sampling room than in the waiting room, which was not statistically significant. On the other hand, the calculation of transmission risk showed that the probability of airborne virus transmission in the sampling room was higher (about 2 to 8%). In addition, wearing masks reduced the possibility of airborne transmission of the virus significantly (77 to 81%).

This study shows that the level of risk in the sampling and waiting rooms is moderate. Masks also significantly reduce the possibility of airborne transmission of SARS-CoV-2. Taking appropriate health and safety measures such as avoiding crowds, wearing masks, whispering, and monitoring social distancing can reduce the plausibility of airborne transmission of the SARS-CoV-2 virus.

Fatigue, caused by prolonged standing activities, affects postural stability through disrupting somatosensory system functions. The application of sub-threshold mechanical vibration can enhance the sensitivity of the mechanical receptors in the sole of the feet. Improved sensory function leads to better movement control and balance. Therefore, this study investigated the effectiveness of vibration-based active insoles in reducing the impacts of fatigue on postural stability among military forces.

Each of the 20 healthy male participants of the study completed three standing balance tests: 1) on both legs, 2) on one leg, and 3) on one leg with a cognitive secondary task for two states of the vibration system (on and off), before and after a fatigue protocol, on a force plate. The activity of leg muscles was also monitored by electromyography (EMG). The mean as a linear index (amount) and the sample entropy (SaEn) as a non-linear index (structure) related to the resultant distance of the body’s center of pressure (CoPRD) displacements, as well as the normalized percentage of the muscle activity level (linear envelope), were used for statistical analyses.

Significant changes in most of the postural and muscular parameters were recorded after the fatigue protocol for the off-mode of the vibration system. Meanwhile, running the vibration system of active insoles was accompanied with no significant differences in the amount and structure of the CoPRD displacements, as well as the activity level of the lateral gastrocnemius and soleus muscles after fatigue, compared to the measurements before fatigue.

The findings confirm the effectiveness of applying sub-threshold mechanical vibration to the sole of the foot in improving standing balance by reducing the negative effects of fatigue on postural stability parameters. Therefore, it is suggested that the use of active insoles can be an effective, feasible, and accessible ergonomic intervention to address fatigue among military forces.

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.

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.

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.

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.

VOCs are harmful air pollutants that must be detected, monitored and eliminated. Adsorber tubes are standard tools for this task, specifically activated carbon tubes with high adsorption and selectivity. This research aims to compare the structural and functional characteristics of domestically produced activated carbon tubes with the conventional commercial ones for sampling toluene, a volatile organic compound.

The characteristics of each adsorbent, such as structure, morphology, porosity, and element composition, were examined by SEM photography, BET testing, and EDAX analysis. The central composite design (CCD) method was employed to investigate the adsorption properties of the adsorbents. The input concentration and readsorption time of the samples were the variables considered in this study. Additionally, a field phase of personal air sampling was performed to evaluate the effectiveness of adsorbent tubes.

SEM and BET analyses indicated that the porous structure of domestic activated carbon was comparable to the model produced by SKC. EDAX analysis detected a minor impurity (1%) in the domestic activated carbon adsorbent. The adsorption performance was significantly influenced by the variations in readsorption time and pollutant input concentration. The accuracy and precision of the performance of the domestic adsorbent tube were obtained as 90.77% and 91.76%. The field phase results demonstrated that the amount of pollutant adsorbed in the SKC-activated charcoal adsorber did not differ significantly during 0 to 30 days. However, the domestic adsorber showed a significant difference in the same period. The overall performance of the two adsorbers did not exhibit a significant difference between 0 and 30 days.

Despite minor structural differences, the adsorption efficiency of toluene by domestic adsorbent tubes in sampling high concentrations is very similar to its commercial type. However, it is not recommended for use in low-concentration environments (10 ppm and less).

Due to the increase in the provision of electronic services to citizens in government offices, the number of computer users and the occurrence of musculoskeletal disorders have increased. Therefore, this study aimed to predict and model the complex relationships between the risk factors of musculoskeletal disorders in computer users working in government offices by an artificial neural network.

The current cross-sectional study was conducted in 2020 on 342 employees of various government offices in Saveh city. First, the researcher visited the work environment to identify the problems and measure the environmental factors. Then, ergonomic risk assessment and psychosocial factors were evaluated using the Nordic questionnaire and the ROSA method. The effect of various factors in causing musculoskeletal disorders was investigated using a logistic regression test.Then the resulting data were collected and modeled by one of the neural network algorithms. Finally, artificial neural networks presented an optimal model to predict the risk of musculoskeletal disorders.

The results showed that by increasing the level of social interactions, the level of demand, control, and leadership in the job, musculoskeletal disorders in men and women decrease. There was a significant relationship between the prevalence of musculoskeletal disorders and job demand, job control levels, social interaction levels, leadership levels, organizational climate levels, job satisfaction levels, and stress levels, in addition between reports of pain in the neck and shoulder and wrist/hand region. There was a significant relationship with the overall ROSA score. Also, there was a significant relationship between the report of pain or discomfort in the neck area with the phone screen risk score, wrist/hand with the keyboard-mouse risk score, and shoulder, upper back, elbow, and lower back with the chair risk score. The accuracy of the presented model for predicting musculoskeletal disorders was also about 88.5%, which indicates the acceptability of the results.

The results showed that several factors play a role in causing musculoskeletal disorders, which include individual, environmental, psychosocial, and workstation factors. Therefore, in the design of an ergonomic workstation, the effects of the mentioned factors should be investigated. Also, predicting the effectiveness of each of the mentioned factors using an artificial neural network showed that this type of modeling can be used to prevent musculoskeletal disorders or other multifactorial disorders.

Falls from height rank among the most frequent accidents encountered in construction workplaces. To mitigate such risks, the utilization of suitable personal fall protection equipment, including safety harnesses, proves to be an effective control measure.

This study involved a comprehensive review of articles pertaining to the study’s objective, published in renowned scientific journals between 2000 and 2021. To achieve this, a meticulous search was conducted across ten scientific-specialized databases, employing eight keywords: “Full body harness,” “fall arrest systems,” “industrial harness,” “harness ergonomic,” “design procedures harness,” “standard for harness,” “fall protection,” and “P.P.E work at height.” The search yielded a collection of relevant articles for analysis and examination.

A total of 101 articles were gathered through the utilization of the specified keywords. Subsequently, a meticulous review process led to the selection of 23 relevant articles for inclusion in the primary study. These chosen articles were categorized into two distinct groups: one focused on the “design of harnesses and optimization of fall arrest systems,” while the other delved into “studies on the consequences of suspension from a height and its effects.” Our findings revealed that 34.7% of the studies evaluated harness safety, 34.7% examined harness ergonomics, and 30.3% investigated suspension consequences.

When a harness is suspended, it leads to physiological changes. Notably, no studies have reported any fatalities resulting from harness suspension. However, the longevity of the suspension greatly depends on utilizing the appropriate harness accessories. The most significant challenge lies in the ergonomic design of the harnesses.