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The objectives of this research were to determine the levels of radioactivity in the Tehran research reactor containment and to investigate the mass-size distribution, composition, and concentration of radionuclides during operation of the reactor. A cascade impactor sampler was used to determine the size-activity distributions of radioactive aerosols in each of the sampling stations. Levels of a and b activities were determined based on a counting method using a liquid scintillation counter and smear tests. The total average mass fractions of fine particles (particle diameter dp < 1 mm) in all of the sampling stations were approximately 26.75 %, with the mean and standard deviation of 52.15 ± 19.75 mg/m3. The total average mass fractions of coarse particles were approximately 73.2%, with the mean and standard deviation of 71.34 ± 24.57 mg/m3. In addition to natural radionuclides, artificial radionuclides, such as 24Na, 91Sr, 131I, 133I, 103Ru, 82Br, and 140La, may be released into the reactor containment structure. Maximum activity was associated with accumulation-mode particles with diameters less than 400 nm. The results obtained from liquid scintillation counting suggested that the mean specific activity of alpha particles in fine and coarse-modes were 89.7 % and 10.26 %, respectively. The mean specific activity of beta particles in fine and coarse-modes were 81.15 % and 18.51 %, respectively. A large fraction of the radionuclides' mass concentration in the Tehran research reactor containment was associated with coarse-mode particles, in addition, a large fraction of the activity in the aerosol particles was associated with accumulation-mode particles.

Traffic accidents are considered a major public health problem in many countries. The aim of this study was to explore the relationships between traffic climate factors (i.e., external affective demands, functionality and internal requirements), driver behaviours, dangerous driving behaviours and traffic accident involvement among taxi drivers. A total of 450 male taxi drivers participated in the study. The traffic climate scale (TCS), the driver behaviour questionnaire (DBQ), the positive driver behaviours scale (PDBS) and the Dula dangerous driving index (DDDI) were used to measure driving behaviours and traffic conditions. The results showed that there was a significant negative correlation between functionality (of the TCS) and the number of accident involvement. Further analysis demonstrated that the effect of risky driving (of the DDDI) on accident involvement was significant. Taken together, these findings suggest that functional traffic systems and driving environments play important roles in traffic accident involvement. [ABSTRACT FROM AUTHOR]

BACKGROUND: Patient safety culture (PSC) as a main component of the organizational culture plays a key role in providing safe, effective and economic cares and services in healthcare organizations. PSC provides a way to assist hospitals in order to improve patient safety and prevent medical errors. OBJECTIVE: The present study aimed to measure PSC and healthcare professionals' attitude towards voluntary reporting of adverse events in two hospitals in Iran and to develop a hybrid intelligent approach for modeling PSC grades. METHODS: The Hospital Survey on Patient Safety Culture (HSOPSC) questionnaire and a two-part questionnaire were used for examining the PSC and healthcare professionals' attitude towards voluntary reporting of adverse events, respectively. Principal component analysis (PCA) was applied to extract of the main components in the HSOPSC questionnaire and to construct 12 dimensions of patient safety culture. The overall grade of patient safety culture was modeled using adaptive neuro-fuzzy inference systems (ANFIS) as a classification problem. RESULTS: Almost half of the participants have experienced a medical error and adverse events. The PSC grade was acceptable from the point of view of 55.5% and 50% of participants in hospital No.1 and hospital No.2, respectively. The overall accuracy of ANFIS in modeling overall grades of patient safety culture in both study hospitals was 0.84. Of those individuals gave an acceptable grade on patient safety culture in both study hospitals, more than 50% believed that all medical errors and near misses should be reported. CONCLUSIONS: The ANFIS algorithm was proposed for modeling and predicting of PSC for healthcare organizations. The results confirm the capability of the proposed model to predict patient safety grades in healthcare settings. [ABSTRACT FROM AUTHOR]

The objective of this research was to determine the effects of heat stress on some hematological parameters and thyroid hormones among foundry workers. This study was performed on 25 heat-acclimated subjects while 10 office workers were selected as the control group. Wet bulb globe temperature (WBGT) was determined to estimate the heat stress. Blood sampling was conducted before and after the daily work shift. The mean value of the WBGT index was 35 °C. The levels of plasma osmolality (p = 0.04) and white blood cells (p = 0.03) in the case group (before exposure to heat) were significantly higher than those in control group. No significant differences were observed between the average levels of T3 (p = 0.79) and T4 (p = 0.17) hormones between two groups. A positive relationship was found between the variation of some hematological parameters and thyroid hormones with WBGT index and air temperature. [ABSTRACT FROM PUBLISHER]

Objectives: Separate exposure to microwaves (MWs) or heat had effects on expression levels of Bax and Bcl-2 and sperm parameters in studied group. Aims: The objectives of this research were to determine the effects of separate and combined exposure to 900-MHz MW (as representative of cell phone radiation) and heat on gene expression and spermogram of male mice. Settings and Design: This experimental animal study was conducted in the school of public health. Materials and Methods: The study was done on 12 male mice randomly divided into four groups (21-23 g): control, test group 1 with separate exposure to 900-MHz MW, test group 2 with separate exposure to hot and sultry climate, and test group 3 with simultaneous whole body exposures to 900-MHz MW and hot and sultry climate. In all studied groups, gene expression and sperm parameters were measured. Results: Tissue samples in all test groups showed integrity of the seminiferous tubule followed by all types of germ line cells. Significant increases in the number of dead sperms in mice with separate exposure to heat were observed in comparison with the other studied groups (P < 0.05). The ratio of Bax expression was elevated to 0.015 ± 0.006 in mice after combined exposures to 900-MHz MW and heat. Conclusion: Separate and combined exposure to 900-MHz MW and heat may induce adverse effects on sperm parameters and gene expression of studied male mice. [ABSTRACT FROM AUTHOR]

The negative consequences of shift work on workers' health and safety increasingly ignored. The major effects include health effects and effects on quantity of sleep, alertness, life satisfaction, and job performance. The aims of this study were to investigate the relationships between shift work and related health effects and shift work and workers' satisfaction in workers of mining industry located in south-west of Iran. All workers of the mining industry were enrolled in this cross-sectional study in 2013. Data were collected by survey of shift workers (SOS) questionnaire. Subjects were divided into case and control groups. The case group included 155 workers employed in shift work schedule and the control group included 104 workers employed in regular day shifts. SOS questionnaire includes questions about demographic features of workers, shift system, health effects of shift work, and the effect of shift work on workers' life satisfaction. Comparisons between the two groups were performed using the chi-square and t-test. The effects of shift work on sleep disorder (P=0.001), tiredness related to shift work (P=0.001), and workers' personal (P=0.003) and family (P=0.005) life satisfaction were significant. The result of chi-square test indicated that workers in the shift work system spent fewer hours with their families (P=0.05) compared with day workers. Comparisons of findings between the shift workers and day workers in study mining industry revealed that shift work is a risk factor for a number of health effects in shift workers. Workers' personal and family life satisfaction has been affected by shift work. [ABSTRACT FROM AUTHOR]

Background: Foundry workers are occupationally exposed to hazardous substances such as silica dusts and toxic gases. The aim of this study was to examine the effects of simultaneous exposure to complex mixtures of silica dust, formaldehyde, and triethylamine on lung function parameters. Study design: A cross-sectional study. Methods: This study was conducted on 55 male workers of core making unit of a foundry plant (the case group) and 55 workers in a food industry were enrolled as a control group in 2015. Workers were monitored for personal exposure to crystalline silica respirable dust, according the NIOSH method No.7602. The concentrations of formaldehyde and triethylamine were measured using a PID instrument. Lung function tests were performed according to the ERS/ATS standards. Results: The mean concentrations of personal exposure to silica dust, formaldehyde, and triethylamine in the core making workers were 0.23 mg/m3 , 2.85 ppm, and 5.55 ppm and respective exposures of control subjects were less than the LOD (limit of detection). There were significant associations between exposure to silica dust and decreases in FVC (Forced vital capacity) values (P<0.05). The findings showed a statistically significant synergistic effect of silica dust and triethylamine on FVC values (P<0.05). Conclusions: The mean exposure of all studied substances was higher than occupational exposure limits. Synergistic effects of exposure to silica dust and triethylamine on some lung function parameters were observed. Simultaneous exposure of foundry workers to silica dust and triethylamine could impair lung function. [ABSTRACT FROM AUTHOR]

Background: Occupational exposure to formaldehyde may decrease white blood cell counts and change blood concentration. In this study, the influences of occupational exposure to formaldehyde on the number of white blood cells and blood concentrations were studied. Methods: This case-control study was conducted in June of 2012 at North Wood Factory, Golestan Province, Iran. The US-NIOSH method No. 2541 was used to determine the occupational exposure of 30 workers of the production line (case group) and 30 administrative staffs (control group) to formaldehyde. The number of white blood cells and blood concentration were determined using the normal blood count method and related indices. Demographic features as well as the symptoms of being exposed to formaldehyde were collected using a standard questionnaire. Results: The occupational exposure of case group ranged from 0.50 ppm to 1.52 ppm. The prevalence of all studied symptoms from formaldehyde exposure in workers (2

BACKGROUND: One of the most important impacts of industrial noise is physiological and psychological effects. The increases in workers' blood pressure and heart rate were detected during and after exposure to high levels of noise. The objectives of this research were to determine whether the noise exposures have any effects on blood pressure and heart rate of workers in the automotive parts industry. METHODS: This case study was done in 2011 at different units of an automotive parts manufacturing in Tehran. Sound pressure level was measured at different units of the factory with a calibrated instrument. Demographic features of workers were gathered with an appropriate questionnaire. Heart rate and blood pressure were measured twice in a day in the start time of work day (before exposure to noise) and middle shift hours (during exposure to noise) in the occupational physician office. For analyzing data, chi-square, independent sample t-test, paired t-test, and analysis of covariance (ANCOVA) were used. P < 0.0500 was considered statistically significant. RESULTS: The average age of workers in the case and control groups was 35.71 ± 8.10 and 33.40 ± 10.41 years, respectively. There was no difference between the average age of case and control groups (P = 0.4360). The results of ANCOVA revealed the significant differences between the mean changes of heart rate F (1, 37) = 26.68, P < 0.0010, systolic blood pressure F (1, 37) = 21.70, P < 0.0010, and diastolic blood pressure F (1, 37) = 26.20, P < 0.0010 of workers in the case and control groups. CONCLUSION: Exposure to industrial noise may increase the heart rate of workers. Although rises in heart rate, systolic, and diastolic blood pressure of workers in the case group were observed after exposure to noise, the values of heart rate, systolic, and diastolic blood pressure were in the normal range. Further experimental investigations are needed to determine the relationships between these variables. [ABSTRACT FROM AUTHOR]

Background: Airborne pathogens play an important role in a hospital air quality. Respiratory infections are the most common occupational disease among the health care staff. The aim of this study was to determine the effect of ventilation system parameters and patient bed arrangements on concentration of airborne pathogens in indoor air of an isolation room. Materials and Methods: A single-bed room was considered in which a patient diagnosed with tuberculosis had been admitted. Five different ventilation types, each at four different capacities were installed in the room while two different locations for the patient's bed were assessed. A direct-impact sampling method (blood agar plate) was used in order to determine the intensity of the bio-aerosols in indoor air of the isolation room. Results: The results showed that when the air was supplied through a circular vent located on the northern wall and the vented air was exhausted via a linear vent located on the southern wall, the average concentration of the bio-aerosols in the air, (with 12 air changes per hour) was reduced to 25 colonies per cubic meter (cfu/m³) (in the range of 25-88 cfu/m³ and a 95 percent confidence interval). In accordance with the analysis applied upon the two different locations of the bed, no significant difference was observed (P>0.05). Conclusion: Installation of ventilation systems as determined by the study is recommended for tuberculosis isolation rooms. [ABSTRACT FROM AUTHOR]

Safety issues have always been put forward as one of the major problems and primary concerns in construction industries in many countries. This paper will focus on the impact of safety training on safety climate and its relevant factors in two sites of a construction firm. The Health and Safety Executive (HSE) guide to safety climate tool that had been validated in Iran was used to determine the impacts of safety training on safety climate and its relevant factors. For this purpose, 347 workers filled out the questionnaire before and after safety training. The relationships between demographic features of workers and safety climate factors were considered in the questionnaire. Spearman's rho test was used to determine the relationship between safety climate factors. In both sites, there were significant differences (p<0.05) between safety climate factors before and after safety training while, the level of safety climate in both sites was the same before (p=0.416) and after (p=0.547) safety training. The results of Spearman's correlations test indicated that there has been a significant relationship (p<0.05) between safety climate and its relevant factors in both sites. The results showed that some safety climate factors such as pressure for production had been influenced by demographic factors such as age and job category. Safety training can improve the level of safety climate and its relevant factors in a construction industry. Improvement of each safety climate factor can promote the level of safety climate. Demographic features affected safety climate level and its relevant factors. [ABSTRACT FROM AUTHOR]

The modeling of kinetic and isotherm curves acquired in adsorption of polycyclic aromatic hydrocarbons (PAHs) as a model compound (phenanthrene) on activated carbons in the organic solvent. All the runs were carried out in a batch system at atmospheric pressure, process temperature of 24±2°C, and using the 100 ml phenanthrene in cyclohexan. This experimental work was mainly focused on the study of how the variables properties such as adsorbent dosage, the initial phenanthrene concentration, contact time and pH of cyclohexane solutions influence the kinetic and isotherm of the adsorption process. The results indicated that pH did not play a key role in the process of phenanthrene adsorption. The considerable adsorption (8.34 mg/g) was reached at pH 7, adsorbent dosage of 0.3 g/100 ml and agitation time of 11 h on activated carbons. The impact of adsorbent dose on phenanthrene concentration was not important after 0.3 g/100 ml. The results also showed that adsorption capacity became notably greater with an increase in contact time and initial phenanthrene concentration. Another important finding was that adsorption processes and equilibrium data well fitted by pseudo-second-order kinetic (R² =0.99) and Fraundlich adsorption models (R² =0.99). It can be concluded that there was a significant positive correlation between adsorption processes and the Freundlich isotherm model but Langmuir theory showed only a weak association. [ABSTRACT FROM AUTHOR]

Background: Many nurses have reported experiencing high levels of occupational stress in their work environment. Stress, as an outcome of stressful workplaces and tasks, affects nursing behavior in hospital wards. The objectives of this research were to determine the prevalence of occupational stress and mental health problems in nurses in the intensive care unit (ICU) at Shahid Mohammadi Hospital in Bandar Abbas in 2013 and to determine the relationship between occupational stress and mental health. Methods: This cross-sectional study was conducted in 2013 on all of the nurses working in ICU at Shahid Mohammadi Hospital located in Bandar Abbas, Iran. Seventy-two nurses were selected as the population for this study, and all of them were female. Two questionnaires were used in this study, i.e., General Health Questionnaire-28 (GHQ-28) for assessing mental health and an occupational stress test for assessing job stress. Furthermore, the relationship between occupational stress and mental health was examined. One-way analysis of variance (ANOVA), independent samples t-test, and Pearson's product-moment correlation test were used to analyze the data. Results: High and moderate levels of occupational stress were experienced by 83.9% and 10.7% of ICU nurses, respectively. The prevalence of mental disorders, somatic symptoms, anxiety, social dysfunction, and depression were 58.9, 60.7, 62.5, 71.4, and 10.7%, respectively. The findings of the independent samples t-test showed that somatic symptoms had significant relationships with age and working experience (p = 0.01). According to the independent samples t-test, there were no significant differences between somatic symptoms and working different shifts (p > 0.05). Conclusions: There was a high prevalence of occupational stress among ICU nurses. There was a significant relationship between occupational stress and mental health. Future interventions are needed to codify a comprehensive health program in this field to reduce occupational stress and enhance nurses' levels of mental health. [ABSTRACT FROM AUTHOR]