New Evidence of the Difference Between Pulmonary Function Parameters of Welders in GMAW , SMAW and FCAW Processes

Background: Welding is a common industrial process which is very harmful to welders’ health. The present study aimed to investigate the effect of toxic gases and metal fumes emitted by three different welding processes on welders’ incidence of respiratory symptoms and pulmonary function.Materials & Methods: This cohort study was conducted in an Iranian shipbuilding industrial factory in 2018. Using the simple census method, 60 welders were selected as the exposed group and 45 staff members of the administrative unit as the control group. Welders’ demographic data and respiratory complaints were collected employing a questionnaire. Fugue and gas samples were sampled from the welders’ respiratory tract and analyzed by standard methods of the National Institute of Occupational Safety and Health (NIOSH). Their pulmonary function was analyzed via forced vital capacity (FVC) spirometric parameters, forced vital volume in the first second (FEV1), and forced vital volume in first second ratio to forced vital capacity (FEV1 / FVC).Results: Among the investigated processes, maximum and minimum mean welders’ exposure concentrations of with total fumes, metal fumes, and toxic gases were observed in GMAW and FCAW welding, respectively. The prevalence of respiratory symptoms in all welders was significantly higher than the control group (p<0.05) in addition, the mean scores of FVC, FEV1 and FEV1 / FVC parameters of welders in all three processes was significantly lower than the control group. Moreover, the spirometric pattern in FCAW and SMAW welders was obstructive, and in the GMAW welders was mixed (obstructive and restrictive pattern).Conclusion: The study depicted that there is a significant increase in the prevalence of respiratory symptoms, pulmonary function, and high concentration of exposure in GMAW welders compared to SMAW and FCAW welders .

Keywords:

Welding processes , fume , gas , pulmonary function , respiratory symptoms , spirometry test