مجله مهندسی بهداشت حرفه ای
سال دهم شماره 1 (بهار 1402)

Noise pollution inside buildings is caused by sound reflection from  internal surfaces. The purpose of the study is to experimentally study the sound emission pattern based on acoustic characteristics in industrial manufactorys.

In manufactorys, rectangular cubes with a volume of less than 2000 cubic meters, between 2000 to 3000 and 3000 to 4000 were made. The reverberation time measurement was based on ISO 2-3382:2008 and the sound emission pattern was measured according to ISO 11690 and the sound level was measured with pink noise. In order to simulate sound parameters, radiation tracking was used in Odeon. Data analysis was done with Spss.

The average reverberation time in manufactorys under 2000, between 2000-3000 and between 3000-4000 cubic meters was 1.75, 2.25 and 2.77 seconds , the measured reverberation time had a significant correlation with the predicted one (r=0.95). The average sound reduction with the distance from the source is 4, 3 and 3 dB, the correlation coefficient between the sound reduction level and the reverberation time (r=-0.97), the correlation between the measured and predicted sound level(r=0.95) was determined.

The reverberation time of the Sabin and Eyring showed higher values than the measurement method. There was a significant relationship between the average noise reduction pattern and the reverbration time. simplicity of the measurement method, the sound reduction criterion can be a good criterion to show the sound emission pattern. It should be used together with the reverberation time to evaluate the sound emission pattern in the manufactorys.

Evaluating safety performance in a work environment is one of the most important steps in establishing an optimal safety condition in an organization. This study was designed and conducted with the aim of evaluating safety performance in a food industry.

This cross-sectional study was conducted in a large food industry in 2021. The sample size in this study was calculated using Cochran's formula with an accuracy of 0.05 equal to 231 people. The studied variables included two groups of reactive (safety training, risk assessment and control) and reactive (type of accidents, unsafe conditions and acts) performance indicators, as well as the final safety performance index. The numerical range of this index was 0.2 to 5.0.

The final safety performance index in this food industry was evaluated as 1.76. The results showed the amount of six groups of safety performance indicators in this industry respectively were estimated, risk assessment (4.01), risk control (3.93), safety training (3.85), type of accidents (2.47), unsafe acts and (2.17), unsafe conditions (2.05). In addition, among the 32 evaluated indicators, the lowest and highest indicators were related to unsafe equipment (0.13) and use of personal protective equipment (2.09), respectively.

The findings of the study indicated that although the level of safety performance in this food industry is not unfavorable, but in order to achieve a favorable safety performance index, practical and beneficial measures should be designed and implemented in line with the six groups of indicators and 32 indicators.

This study aims to provide a risk assessment method based on a fuzzy Bayesian network (FBN) to prevent the failure of firefighting systems (FSs).

In this research, the fault tree structure was validated, and the failure factors were identified. Triangular fuzzy numbers and the combined CoA/Sum-Product method were used to calculate the failure probability. Then, deductive and inductive reasoning and sensitivity analysis were performed using fuzzy logic and fault tree transmission in a Bayesian network (BN).

The results of a case study in methanol storage tanks showed that the combination of FBN and validation of structures can be presented as a suitable method to evaluate the reliability of FSs. The content validity index of the final basic events was over 0.79. The highest and lowest failure probabilities were related to foam system failure and valve failure, respectively. Also, the failure probability for the failure of FSs was 5.7E-6 based on a fuzzy fault tree (FFT). After updating with BN, the previous probability of failure of FSs with FBN was calculated to be 0.022978, which was greater than the value of the FFT. The reliability of the system was equal to 0.77022.

the present approach can help the decisions of managers and analysts of the petrochemical industry to prevent the failure of FSs in tanks due to changes in systems.

Human error is the leading cause of accidents in industries. The purpose of this study was to evaluate the safety culture and model the factors affecting it in a process industry using the structural equation modeling.

In this cross-sectional study, safety culture was assessed using ten dimensions’ questionnaire constructed by researchers with Likert-scale. This study was conducted in a petrochemical industry in 2021. Questionnaires were distributed among 312 employees and 308 questionnaires were completed. SPSS 23.0 and AMOS 23.0 were used to analyze the data.

The safety culture score was calculated to be 3.35. The results of SEM demonstrated that the factor loadings of the effect of income, education, and work experience on safety culture were 0.322, 0.445, and 0.328, respectively, and the factor loadings of the effects of education, work experience, and age on accident experience were -0.336, -0.312, and -0.214, respectively. The relationship between safety culture and accident experience had a factor loading of -0.477, and GFI was 0.97.

The results of the safety culture assessment indicated that this organization has a positive safety culture, with a high score related to the dimensions of utilizing protective equipment, training and understanding of issues, and the commitment of managers and supervisors. The results of structural equation modeling revealed that education, income, and work experience all have a positive impact on safety culture. Accident experience was inversely related to factors such as age, education, and work experience, and safety culture was likewise inversely correlated to accident experience.

Providing safe and high-quality care during crises such as natural disasters, conflicts, or epidemics should always be one of the fundamental goals of a health care system. In health care, in addition to patients, employees are also affected. Therefore, this study aims to investigate the state of HSE culture and its relationship with the infection of Covid-19 in health and treatment centers.

The current cross-sectional-analytical research was conducted using the standard HSE safety culture questionnaire and the PCR test to measure employees' exposure to Covid-19. The study subjects were randomly selected for investigation. In the following, SPSS version 22 software was used to analyze the data.

This study's participants were 452 employees working in the Corona Center Hospital of Borujerd city with an average age and standard deviation of 33.97 ± 5.69. The mean and standard deviation of the overall HSE culture score was 172.64 ± 23.53, 7.1% of people had a negative HSE culture, and 92.9% had a positive HSE culture. Examining the condition of covid-19 infection shows that 70.1% of people are infected with the virus. The results of multivariable linear regression showed that with increasing age, the overall score of HSE culture decreases (p-value=0.0001).

The results showed that the HSE culture in the health workers of the studied hospital is at a high level. The variables of age, history of accidents, illness, and job type affect the HSE culture score.

Low back pain is one of the most common musculoskeletal disorders and an important cause of early retirement due to disability in employees in industrialized and developing countries. The present study aimed to determine the work ability index and its relationship with low back pain among employees of the Tehran offset printing industry.

A cross-sectional study was performed within six months in 2020.  Data from 220 employers working in the offset printing industry were collected through survey questionnaires including Nordic Musculoskeletal Questionnaires (NMQ) and Work Ability Index (WAI). Data analysis was performed using SPSS software version 24 with a significance level of P-Value <0. 05.

In general, more than half of the participants (%62.5) indicated high symptoms of Low Back Pain. Also, the results of the Pearson correlation test showed that there is a positive and significant correlation between the level of work ability and the severity of low back pain (p<0.001).

The high incidence of low back pain among printing workers makes it necessary to provide safety and health training programs on managing and improving workability.

Work stress is a negative physical and mental reaction that is the second most common work-related problem after musculoskeletal disorders. Fatigue is a state that occurs during a work period and because of that, a person loses his efficiency. This study was conducted to determine the relationship between job stress and job fatigue in nurses.

It was a cross-sectional descriptive-analytical study that was conducted in teaching and therapeutic hospitals of Gorgan city including Sayad Shirazi Hospital, 5 Azar Hospital, and Taleghani Hospital in 2021.277 nurses were included in the study after random stratified sampling. Data were collected by OSIPOW job stress questionnaires and Swedish SOFI job fatigue questionnaires.

The mean score of job tension was 180.05 ± 23.4 that was classified as moderate to severe.    The highest score was related to the role workload dimension and the lowest was related to the physical environment dimension. The mean score of job fatigue was 53.18 ± 22.5 and was evaluated at a lower than average level. The highest score was related to the dimension of lack of energy and the lowest was related to the dimension of physical effort.

Considering the relationship between job stress and job fatigue, it is suggested to provide the necessary infrastructure and facilities to reduce the stress in nurses and provide training on how to deal with the stress to the hospital staff.

The coronavirus spread faster in crowded public places. Thus, industrial workers are more prone to COVID-19 infection. The present study aims to evaluate the prevalence of COVID-19 and its association with adherence to sanitary protocols in detergent industries in Alborz province, Iran.

Given a 95% confidence interval, a 3% allowable error level, and an 11% prevalence rate, a total sample of 552 from seven industrial units were recruited. Demographics and COVID-19 infection data were gathered using a questionnaire. The level of adherence to sanitary protocols was assessed using a checklist approved by the Ministry of Health.

The average age of subjects was 35.17±7.27 years, and 14.3% were female. The level of adherence to sanitary protocols was 94.36±6 percent in each industry. The prevalence of COVID-19 infection was 33.5% in detergent industries, with the highest rate in the packaging unit (42%). The results suggested that coronavirus prevalence was associated with education level, history of an infected family member, exposure to crowded places, and disinfection (p<0.05).

The contact history of workers with an infected family member plays a significant role in their coronavirus contraction. Enhancing air-conditioning systems, social distancing in working stations, evaluating the workers with a history of contact with infected family members, and developing management measures, including educating their families and furloughing workers in contact with infected family members are integral for the prevention and control of the epidemic in industries.