pISSN: 2008-5109
eISSN: 2008-5435
Editor-in-Chief:
Mohammadreza Monazzam Esmaeilpour, PhD.
Vol 17 No 2 (2025)
Published:
2025-12-09
Original Article(s)
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Background: Workplace noise is one of the most significant occupational hazards and can adversely affect workers’ health. This study investigated the prevalence of noise-induced hearing loss (NIHL) and its association with blood pressure (BP) among workers in an Iranian oilfield.
Methods: This cross-sectional study included 670 male workers, excluding those with cardiovascular conditions or specific ear-related symptoms. Noise exposure and hearing thresholds were assessed. BP was recorded using a digital sphygmomanometer, with hypertension defined as systolic BP (SBP) ≥140 mmHg or diastolic BP (DBP) ≥90 mmHg.
Results: A 12.7% prevalence of NIHL was observed, including mild (6.2%) and moderate (2.1%) cases. Workers with NIHL had significantly higher mean SBP (118.16 vs. 115.81 mmHg, p = 0.01) and DBP (77.45 vs. 75.53 mmHg, p = 0.001) compared to those without NIHL. The prevalence of hypertension was 2.7%.
Conclusion: The findings suggest that chronic noise exposure may contribute to both cardiovascular and auditory damage, likely due to noise-triggered stress responses. -
Background: Rapid industrialization has led to a significant increase in work-related musculoskeletal disorders (WMSDs), driven by factors such as job demands, repetitive motions, workload intensity, and prolonged task durations. In the food industry, repetitive movements inherent to the work environment further elevate the risk of WMSDs. This study investigates the relationship between musculoskeletal disorders and occupational burnout among employees at the Bistoon Sugar Factory in Kermanshah.
Methods: This descriptive survey included all 300 employees of the Bistoon Sugar Factory, selected through census sampling. Participants with pre-existing musculoskeletal conditions or injuries affecting the musculoskeletal system were excluded. Data were collected using the Nordic Musculoskeletal Questionnaire and the Maslach and Jackson Job Burnout Inventory. Reliability analysis using Cronbach’s alpha yielded coefficients of 0.948 for the burnout inventory and 0.757 for the Nordic questionnaire. Data were analyzed using SPSS version 22, employing Pearson’s correlation and regression analysis.
Results: Significant positive correlations were found between musculoskeletal disorders (MSDs) and components of occupational burnout (p < 0.001). The strongest association was observed between MSDs and reduced personal accomplishment (β = 0.212–0.282). The modest R² values suggest that other unmeasured variables may also contribute to burnout.
Conclusion: The high prevalence of musculoskeletal disorders (MSDs) negatively affects task performance and job satisfaction. Implementing ergonomic adjustments, targeted training programs, and organizational support systems can help mitigate these disorders and enhance workplace adaptability. Such interventions have the potential to improve both employee well-being and the overall quality of services. -
Background: The COVID-19 pandemic was a public health challenge that put health systems in a highly vulnerable situation, especially nurses working in intensive care units (ICUs) who provided care to patients with COVID-19. The goal of this study was to explore the lived experiences of ICU nurses regarding the nursing heightened job demands during the acute phase of the pandemic.
Methods: The present study was conducted using a qualitative description design and purposive sampling method. The data of the study was collected through semi-structured interviews with 17 nurses in the special care departments of private and public hospitals in Tehran, during the earliest phases of COVID-19 pandemic, i.e., spring and summer of 2020. Data analysis was done using conventional content analysis method through MAXQDA 2018 software. The trustworthiness of the study findings was also confirmed by the researcher triangulation, peer review and member check.
Results: Based on the lived experiences of the nurses, the challenges in the nursing job demands during the pandemic were demonstrated in 8 themes, including 1. Patients with complex, high-care needs, 2. ICU working at its limit, 3. Supervising and orienting the new workforce, 4. Care and treatment ambiguity, 5. Enduring the burden of PPE, 6. Covering for the unavailable colleagues, 7. Being emotionally involved with the patients and their families, and 8. Exhausting schedules. The breadth of these themes shows that ICU nurses faced unprecedented physical, mental and emotional demands during the period.
Conclusion: The findings of this study reveal the profound impact of the COVID-19 pandemic on ICU nurses, highlighting the multifaceted extreme demands placed upon them. The results underscore the need for targeted support and resources to address the challenges faced by these frontline workers, including physical strain, emotional burden, and the complexities of patient care. It is crucial for healthcare systems to develop strategies that mitigate these pressures and provide robust support systems for nurses. Addressing these issues is essential to ensure well-being of ICU nurses and the sustainability of high-quality patient care during future crises. -
Background: Reading and studying on digital devices—such as personal computers, laptops, and mobile phones—has become integral to daily life. The shift from paper to electronic formats has raised concerns about the impact of digital devices on human performance and health. The current study aimed to compare the effects of paper and electronic devices on perceived fatigue, workload, usability, and comprehension.
Methods: Thirty-six participants (58.3% female) read general passages on three devices in 2021: a laptop, a mobile phone, and paper. After each trial, participants answered ten comprehension questions to assess their understanding. Additionally, fatigue, mental workload, and usability were evaluated using a visual analog scale, NASA-TLX, and the System Usability Scale (SUS).
Results: The results showed that 69.4% of participants preferred reading on paper over screens. The average scores for fatigue (22.64) and workload (40.47) were lower for paper. The usability score for paper was higher (88.44) than for the mobile phone (68.17) and laptop (68.44). While comprehension scores were higher for paper (4.36) than for laptop (4.19) and mobile phone (4.22), the difference was not statistically significant.
Conclusion: Despite the widespread use of electronic devices for reading, paper was rated significantly higher in terms of usability and cognitive workload, although it showed no statistically significant advantage in comprehension. -
Background: Iran’s hot and arid climate, combined with frequent exposure to heat-generating industrial processes, presents significant occupational health concerns. These environmental conditions may influence white blood cell (WBC) levels and their functions in response to heat stress. This study investigates the relationship between the Wet Bulb Globe Temperature (WBGT) index and WBC levels among workers in a foundry setting.
Methods: This descriptive-analytical study was conducted on 55 male workers from two sections of a foundry: the cast iron section (35 participants) and the CNC section (20 participants). Blood samples were collected from all participants. Heat stress was assessed using the WBGT index. Intervening parameters—such as noise, lighting, and metabolic rates—were measured for each work group. Data analysis was performed using SPSS version 16.
Results: In the case group, a decrease in total WBC count and lymphocyte levels was observed, along with an increase in neutrophil levels and the neutrophil-to-lymphocyte ratio. No significant relationship was found between heat stress and the composition of other WBC types, including basophils, monocytes, and eosinophils. Correlation analysis revealed strong associations between the WBGT index and total WBC count (R² = 0.93), neutrophils (R² = 0.85), lymphocytes (R² = 0.81), and overall WBC composition (R² = 0.82).
Conclusion: Chronic exposure to heat stress may lead to significant alterations in WBC levels, potentially weakening and suppressing the immune system. The blood parameters examined in this study can serve as biomarkers affected by heat stress and merit further investigation. -
Background: Noise-induced hearing loss (NIHL) is among the most prevalent occupational disorders in industrial settings, particularly in the automotive manufacturing sector. Despite extensive noise exposure, variability in hearing outcomes suggests the presence of multiple occupational and non-occupational contributing factors.
Purpose of the study: This study aimed to evaluate the hearing status of employees in a major automobile manufacturing company and to compare the prevalence and severity of hearing loss between noise-exposed production (blue-collar) workers and non-exposed administrative (white-collar) staff.
Methods: A cross-sectional study of 2,312 male workers (2,136 blue-collar, 176 white-collar) assessed hearing thresholds via pure-tone audiometry. Hearing loss was defined as >25 dB HL. Demographic and occupational data were analyzed using descriptive and inferential statistics.
Results: The mean age was 42.9 years. Hearing loss >25 dB HL was under 10% across all subgroups. No major differences in overall thresholds were found, though white-collar workers showed slightly greater hearing loss at select low and high frequencies, despite no occupational noise exposure. Differences were statistically, but not clinically, significant.
Conclusion: These findings suggest that occupational noise exposure alone does not fully explain hearing loss among industrial workers. Better hearing outcomes in noise-exposed blue-collar workers may reflect the effectiveness of structured hearing conservation programs and pre-employment screening. In contrast, white-collar staff may experience hearing decline from non-occupational sources. The results underscore the importance of the Healthy Worker Effect and highlight the need for future research to account for worker selection, health surveillance practices, and prior noise exposure beyond the workplace. -
Background: This study aimed to evaluate the ergonomic suitability of barefoot shoes by assessing key usability indicators, including comfort, perceived pain, user satisfaction, and plantar contact pressure during simulated office tasks.
Methods: In this ergonomics field study, eight ergonomists selected their appropriate barefoot shoe size using a sizing scale and wore the shoes for eight hours. Their daily office routine included two hours of movement around the work environment at the start of the workday, followed by six hours of sedentary office and administrative tasks. At the end of each evaluation phase, participants completed questionnaires assessing foot pain, perceived discomfort in the lower limbs, satisfaction, and overall usability. Additionally, plantar contact pressure was measured in one participant (50th percentile) using the Ergo FS16 device across five anatomical regions of the foot.
Results: All participants (100%) reported that the shoe size selected via the sizing scale accurately matched their foot dimensions. Subjective discomfort levels remained minimal, with average scores of ≤1 in the calf and ankle regions at both 2-hour and 8-hour intervals. The heel region showed a slight increase in pain scores, from 1.25 at 2 hours to 2.1 at 8 hours, while all other foot regions reported no pain or discomfort. User satisfaction scores were consistently high, exceeding 7 out of 10 at both evaluation points. Usability assessments indicated that 75% of participants rated the shoes as acceptable, while 25% provided borderline acceptable ratings. Objective contact pressure measurements confirmed that all recorded values across the plantar surface remained below the established pain threshold.
Conclusion: The findings demonstrate that the barefoot shoes evaluated in this study are suitable and highly comfortable for prolonged standing and daily office tasks. The minimal reported discomfort and high user satisfaction scores support their ergonomic efficacy. However, further longitudinal studies are recommended to assess the long-term effects of barefoot shoe use, particularly in relation to musculoskeletal health and occupational performance. -
Background: Research on Indoor Air Quality (IAQ) in residential settings is limited, despite its importance for occupant health—especially during pandemics like COVID-19. Computational Fluid Dynamics (CFD) is a valuable tool for assessing IAQ parameters. This study aims to apply CFD to simulate air movement and velocity patterns in a living room to identify strategies for reducing coronavirus exposure.
Methods: A 3D model of a living room was created using GAMBIT software. Airflow simulations were performed using ANSYS FLUENT. The CFD model was validated by comparing computed air velocities with experimental measurements. Twelve scenarios were simulated, considering four different air supply locations and three Air Changes per Hour (ACH) rates (3, 6, and 8).
Results: The validation showed a maximum error of 14% and a root mean square error of 0.1 for air velocity, confirming the model’s accuracy. Analytical calculations for a 10 μm particle showed a terminal settling velocity of 0.302 × 10⁻² m/s and stopping distances of 0.0089 m and 0.011 m for breathing and talking, respectively. The highest mean air velocity (0.31 m/s at 1.1 m height) was achieved in Scenario 4 with an ACH of 8.
Conclusion: The location of the air supply and the ventilation rate significantly impact airflow patterns and can reduce exposure to airborne pathogens. Using mechanical ventilation and avoiding family gatherings are crucial for exposure control. The findings suggest that strategic ventilation design is essential for creating healthier indoor environments during a pandemic.
