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Background: Occupational accidents occur every day across industries. One of the probable causes of this occurrence is the sleep disorders. This study aims to investigate the relationship between the sleep disorders, and occupational accidents in a group of Iranian workers. Methods: A cross-sectional study was conducted on 366 workers of steel parts production industries in Kashan, Iran. A three-part questionnaire was used in the study. The first part covered the demographic characteristics of the workers, the second part was related to the Pittsburgh Sleep Quality Index for sleep disorders and the third part was related to the information on the accident occurrence in the workplace. The collected data were analyzed using SPSS software and analyzed with Pearson correlation coefficient, ANOVA and t-test. Results: The results of this study showed that the average score of sleep quality was 5.84 (standard deviation: 2.66). The sleep quality of 53.7% of the subjects was poor. Over the past year, 27.4% of the workers had an occupational incident. There was no significant relationship between sleep disorders and occurrence of occupational accidents (p> 0.05). Conclusion: Our results showed that more than half of the workers suffered from poor sleep quality. However, there was no significant relationship between sleep disorders and occupational accidents.

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Background: According to the Labor Code, one of the important duties of employers in the field of safety and health is the provision of personal protective equipment and its training to workers. How to train workers who are willing to use the earmuff all the time is an issue that needs to be addressed. Therefore, the aim of this study was to determine the effectiveness of a training intervention with the BASNEF model in increasing the duration of the use of hearing protective equipment by workers. Methods: This is an evaluation study that was carried out in Yazd tile industry in 2015. The research population in this study was 50 workers who were trained according to the BASNEF model. After developing a questionnaire based on the structures of Kirk Patrick's evaluation model, with the acquisition of validity, trained workers completed the questionnaire. Results: The highest mean scores were respectively in the results 87.06 (12), behavior 86.30 (9.59), learning 84.87 (13.55), content 81.36 (10.70) and the response 81.28 (11.33). In general, the score of the evaluation domains is above 80.Conclusion: According to the findings, BASNEF‘s training course is effective in increasing the duration of workers' use of protective hearing equipment.

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Background: Noise-induced hearing loss (NIHL) is a debilitating and irreversible disease and one of the ten most important occupational diseases. The purpose of this study was to investigate the relationship between individual risk factors and NIHL in textile workers. Methods: This cross-sectional study was carried out on 128 employees of one of the textile factories of Tehran Province in 2017. At first, data were collected using a demographic questionnaire including age, marital status, level of education, and work shift. Then, using an audiometer, the workers' threshold of hearing was measured in both ears for frequencies of 500, 1000, 2000, 4000, and 8000 Hz, and data were analyzed by the SPSS version 18.Results:The mean age of the workers was 30.59 ( 3.5) years, their mean work experience 5.7 (2.76) years, and the mean environmental noise level at work 87.88 ( 6.13) dB. The findings showed that there was a significant relationship between the level of exposed noise and age, education level, work shift, and marital status. Conclusion: Increased age of population and level of environmental noise are two factors for increased hearing loss, which can be partly prevented by using engineering approaches such as using mufflers and silent rooms.

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Background: The sick building syndrome (SBS) is known as an unhealthy condition of occupants of a building, caused by environmental factors such as small space, poor ventilation, and different pollutants in the building. Symptoms of SBS include anxiety, respiratory, dermal, and sensory problems which start by entering a building or slightly after that, and disappear after leaving the building. The aim of this study was to determine the frequency of SBS in the employees of Shahid Beheshti hospital of Kashan. Methods: In a descriptive, cross-sectional study conducted, a sample of 279 randomly-selected employees of Shahid Beheshti hospital in Kashan working during 2016-2017, were involved. The study was performed on four groups of doctors, nurses, servants and employees. To collect the data; a questionnaire was used. It consisted of two parts: demographic data and questions of SBS questionnaire of World Health Organization. The collected data were analyzed using SPSS; and statistical tests such as Chi square and Fisher's exact test were performed and logistic regression were used for multivariate analysis. Results: The prevalence rate of SBS in general, in women and in men was estimated 50.81%, 55.3% and 44.7%, respectively. Symptoms of indisposition (47.3%), skin dryness (41.5%) and headaches (38.9%) had the highest frequency. Studying SBS symptoms in different job groups showed that skin dryness and dry and sore throat in physicians were significantly less than those in the other groups (p<0.05). In logistic regression analysis, the only factor influencing SBS was the staff height (p=0.02). Conclusion: Considering the high prevalence of the symptoms of building syndrome in all of the four groups, paying more attention to improving the working environment, such as the efficiency of the air conditioner system and increasing the entry of fresh air into the departments, increasing the quality of work life would be of utmost importance which would result in motivating and increasing the productivity in the work environment.

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Background: Exposure to noise causes auditory and psychological effects in humans. Among the sources of sound generation are the means of transportation, which can cause anger and aggression. The present study was conducted with the aim of investigating the relationship between living in different places in terms of traffic and noise sensitivity with aggression in housewives in Yazd city. Method: This was a cross-sectional study conducted in 2019-2020 among housewives in Yazd city. First, the city of Yazd was divided into three areas with high, medium and low traffic using GIS software, and 100 people from each area, were included in the study in a stratified random manner. Information was collected using Weinstein's bass and Perry questionnaires and sensitivity to sound. Finally, the data were statistically analyzed using SPSS version 24 and R version 4.0.2. Result: Findings revealed that those who lived in high traffic have a higher aggression score (P-Value=0.009), while no significant difference was observed in the noise sensitivity score among people of different groups (P value=0.071). In addition, a direct and significant relationship was observed between aggression and sensitivity to sound (r=0.28 and P value<0.001). Only two variables of noise sensitivity and place of residence were included in the regression model and (R Square) was equal to 0.096. Conclusion: The results showed that the two factors of traffic load and noise sensitivity have a direct and significant relationship with aggression scores among housewives in Yazd city. It is also suggested to use different sound insulation and barriers in buildings.