Journal of Health and Safety at Work

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Introduction: Construction industry plays a major role in the economic development of all countries and among the various occupations, this industry is one of the most dangerous industries, particularly respiratory contaminants, around the world. The aim of this study was to evaluate the respiratory capacity of construction workers, working in different workshops in Tehran city and developing a regression model to examine the relationship between pulmonary capacities with the type of occupation, work experience and tobacco smoking.
Material and Method: This study was a cross-sectional descriptive study conducted among 628 construction workers in Tehran city in 2017. After data collection, data analyses were performed using statistical independent t-test, one way ANOVA and correlation tests by SPSS software version 22. Also, multiple backward regression was used to check the effect of independent variables on lung function.  
Result: According to the results of this study, a significant relationship was found between age and work history with the pulmonary function indexes (FVC, FEV1, FEV1/FVC and FEF25-75%) (P-value<0.001). The average of FEV1/FVC% was significantly different among various occupational groups (p-value<0.001). In the analysis of the findings of the pulmonary function test in the exposed group a separate model was made using multiple linear regression for each of the pulmonary functions, and the independent variables including age, work experience, job type and cigarette addiction were entered into the model.
Conclusion: The present study showed a significant change in the pulmonary function parameters of the construction workers and the chance of pulmonary disorders might be high among these individuals.

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Introduction: The respiratory system, one of the most important organs of the body, can be affected by adverse effects, disorders and consequences in the workplace. Spirometry is one of the most important screening and testing tools in the periodic medical examination of every employee. This study was aimed to evaluate the factors affecting the respiratory function of staff of Tehran University of Medical Sciences (TUMS).
Material and Methods: This descriptive-analytical and cross-sectional study carried out on 300 employees of TUMS according on during the enrollment phase of the Tehran University of Medical Sciences employee’s cohort (TEC) study was in order to survey the parameters affecting pulmonary function. Demographic data were collected through a demographic questionnaire. Spirometry was used to evaluate respiratory function parameters and bioelectric impedance was used to analyze body composition. Data analysis was performed by SPSS software version 25. Two-sample t-test, one-way ANOVA, and Pearson correlation coefficient were used for statistical analysis. Multiple linear regression was used to determine the effect of independent variables on the parameters of pulmonary function.
Results: It was found that 73.6% of the subjects had a normal lung pattern, 7% had an obstructive pattern, 14.7% had a threatening pattern and 4.7% had a mixed pattern. There was a significant negative correlation between FVC and FEV1 parameters and smoking (P-value <0.05). There was also a significant relationship between FFM, age and BMI with FEV1/FVC (P-value <0.05). Similarly, there was a meaningful relationship between type of job and FVC parameter (P-value <0.05). The findings showed that the highest and the lowest averages of all parameters of pulmonary function was in administrative and occupational services, public and technical services and facilities, security and guard, respectively.
Conclusion: In the present study, it was found that occupation type affects lung function due to exposure to contaminants in different groups. Other factors affecting lung function included age, body mass index, fat mass, fat free mass and smoking. Therefore, changing lifestyle such as proper diet, regular exercise and not smoking can be an effective step towards improving the parameters of lung function.