Evaluation of local exhaust ventilation system performance for control of Fe2O3 dust at an iron making unit

Introduction: Adherence to the design values and ventilation standards (VS) after installing and also maintaining continuous work of ventilation system with maximum performance throughout its life are amongst the reasons of ventilation systems monitoring. Therefore, the aim of this study was to evaluate performance of local exhaust ventilation system for control of dust by measuring the operating parameters and also to compare it with ventilation standards (VS) and design values. Material and Method: The present research is a descriptive and cross-sectional study, conducted in three sections of measuring, monitoring and evaluating the operating parameters on hoods, channels and fan of ventilation system based on the current status of the system, documentation (design), and recommended standards (VS). Static pressure, velocity pressure, surface area, and flow rate were measured based on the recommendations of various sources and ACGIH industrial ventilation manual, and the data were compared with the design and recommended values, using the SPSS software version 16.   Result: The results of paired sample t-test between flow rate and velocities of design and current status, showed significant differences in various parts. Accordingly, the results revealed a reduction of more than 50% in the design duct velocity compared to the current duct velocity, while design duct velocity is 1.3 more than the standard duct velocity of current status, and current duct velocity is about 65% of standard duct velocity. Conclusion: The reduction and nonconformity of the results of measurements of operating parameters (after a minimum of two decades) with design and standard values are corroborant and sufficient reason for obstructions, abrasions, leaks, imbalance of system ducts and their inefficiency in some branches. Since there is no base line measurements for system (supposing that the system worked with maximum amounts of setup time), one of the reasons for these changes can be attributed to lack of schedule for regular and appropriate maintenance

Evaluation of Health, Safety, and Environment Attitude among Office Workers

Introduction: Nowadays, health, safety, and environment (HSE) management system is employed and implemented comprehensively in order to reduce accidents, create a safe environment and increase workers' productivity in workplaces. The aim of this study was to determine the condition of HSE at Shahroud University of Medical Sciences. Methods: This cross-sectional study evaluated the status of HSE at office environment from the perspective of 81 staffs and occupational hygienist .Data collection tools consisted of a self-made checklist adapted from the provided checklists by the authoritative organizations. Data were analyzed using SPSS16 statistical software through descriptive statistics and statistical tests including Pearson correlation and independent T-test. Results: HSE components' average from users and interviewers' perspectives were 0.51±0.15 and 0.6 ±0.15, respectively. Safety had the worst situation form participants' perspective with average 0.499±0.02 and 0.489±0.02, respectively. However, the best situation was attributed to the physical agents section with an average of 0.69±0.028 and 0.72±0.025, respectively. There was a significant relationship between users and interviewers' perspectives regarding Ergonomic and Physical agents. Conclusion: By taking into account the facts that HSE average score was low and the study was conducted in the one of the administrative units of universities affiliated to the Ministry of Health, which itself is part of the HSE trustee, further attention is required to the implement and establish the HSE management syste

Investigation the prevalence of COVID-19 in different occupations in Shahroud city

Introduction: Covid-19 was first reported as a viral disease in China in 2019, and it soon became a global pandemic. In addition, the types of occupations people have and the environments in which they work may increase the likelihood of being exposed to the virus. Thus, this study was conducted to investigate the prevalence of Covid-19 disease in various occupations and its relationship with some effective parameters in Shahroud city. Methods: This research is a cross-sectional, descriptive-analytical study that was conducted in 2021. The required information was extracted from the database provided by Shahroud University of Medical Sciences. These files contain the results of the comprehensive study of COVID-19 in Shahroud. All the jobs that were asked of the person were classified based on International Standard Classification of Occupations and suspicious and definite cases were examined in different occupation. The information analyzed using SPSS software version 22. Results: According to the results, the highest percentage of cases (45%) was in healthcare workers, such as doctors, nurses, and operating room staffs—in other words, all employees working in the healthcare system. The next highest percentages were in household and home nursing workers (44.5%), retirees (43.2%), and construction workers (43%). The relationship between variables such as age, smoking status, presence of comorbidities, and presence of a high body mass index (BMI) associated with Covid-19 disease was examined by the regression test. It was found that the relationship was significant, that these variables affected the prevalence of the disease. Based on the odds ratio in the age variable, with each year of age, the chance of getting infected increased by 1%. A current smoker had a reduced chance of getting the disease by 57.2%. Having a comorbidity increased the chance of getting the disease by 14%, and with each increase in BMI, the chance of getting the disease increased by 3.8%. Conclusion: The study found that in some occupations, such as healthcare worker, the prevalence of the disease was higher because workers were in direct contact with patients and people infected with the virus. In general, it can be said that the prevalence of the disease was low in workers who could telework and remain at home rather than go to a job or in the community. Factors such as age, the presence of comorbidities, status as a current smoker, and having a high BMI had an effect on contracting Covid-19 disease

Assessment of Interior and Area Artificial Lighting in Hospitals of Hamadan City

Background & Objectives: Comfort lighting is one of the most important topics, which provides optimum physical conditions in general environment and workplaces such as hospitals. This study aimed to evaluate general, local and area artificial illumination of Hamadan city hospitals . Methods : In this descriptive-analytical study, general, local and area artificial illumination in seven Hamadan hospitals in 2006 were evaluated. Lighting intensities (illuminance) were measured according to recommended IESNA method using the lux meter model (Lutron-Lx102) in the early hours of night. Lighting quality parameters such as color rendering, technical suitability of design and lighting uniformity were evaluated. Data was analyzed using SPSS 13 . Results : The average of interior illuminance was 90.44 ± 46.97 lx, which was lower than the national recommended limits. Maximum and minimum intensity values of interior illuminance were in nursing station and laboratory, respectively. The average of area illuminance was 47.92 ± 53.2 lx and local illuminance was 131.5 ± 60.2 lx, which were lower than the recommended limits. Maximum intensity of local illuminance was in laboratories and the minimum levels were in admitted rooms, checkup and injection units. In total, 90.6% of general interior lighting systems, 83.3% of area lighting systems and 100% of local lighting systems had unaccepted design . Conclusion : The average of general, local and area illuminance in Hamadan hospitals were not within the acceptable limits for comfort lighting. To obtain comfort lighting in studied hospitals, reforming and modifying lightening systems is necessary

Efficiency Assessment of Local Exhaust Ventilation Hoods System for Control of Fe2O3 Dust in the process of Oxide Screen Unit at iron making in steel industry

Background & Objectives : Local exhaust ventilation system (LEV) is one of the most common engineering controls methods for the chemical agents in workplaces. This study aimed to determine the efficiency assessment of the LEV system for control of Fe2O3 dust in the process of oxide screen unit at iron making in steel industry . Methods : The LEV system with an extensive network of ducting including 17 hoods was investigated in a cross-sectional study. The First, variations and contradictions of the system and process were compared versus documentation (system plans), then hood Efficiency Assessment accomplished by using of the dust concentration measurement besides of the each hood (source), at two status ON and OFF of LEV system (Repeat three times), by NIOSH 500 method. Results : Result of statistical test between the concentration of pollutants at two status ON/OFF of LEV system, in 7 of 17 hoods, didn’t show significantly different (P <0.05). Enclosed hood at the material falling from the tank to the feeder, with 85% efficiency and 3.3±1.5mg/m3 concentration at ON status was the highest efficiency. Two hoods, one enclosed hood at material falling from the Feeder into the screen and other unenclosed at material falling from conveyor to conveyor (small size at below screen), both with 2% efficiency and the 243.2±73.5 and 3462.4±1339 mg/m3 concentration demonstrated the lowest efficiency at ON status. Also the highest concentration of contaminants was at the unenclosed hood installed in the place of pellets falling from the conveyor into the tank with 5.03g/m3 and efficiency of 7%. Conclusion : The few hoods of the investigated LEV did not have appropriate performance and had different efficiency. Even, some hoods (branches) show negative efficiency due to return of contaminant from the hood to workplace area