Abstract

In order to study the effect of welding fume exposure upon the pulmonary function test, we examined 131 shielded arc welding workers, and 152 CO2 arc welding workers as cases and 172 control workers for their general characteristics, and forced vital capacity (FVC), forced expiratory volume in one second (FEV1.0) forced expiratory volume in one second as a percent of FVC(FEV1.0%), and maximal mid-expiratory flow (MMF) were obtained from in the spirogram. In shielded arc welding group and CO2 arc welding group, FVC, FEV1.0, FEV1.0%, and MMF were significantly decreased than control group, especially marked in the MMF finding. The distribution of workers below normal range was as follows: in the shielded arc welding group, 2 workers(l.5%) for FVC, 17 workers(13.0%) for FEV1.0, 5 workers(3.8%) for FEV1.0%, 28 workers(21.4%) for MMF, and in the CO2 arc welding group, 3 workers(2.0%) for FVC, 25 workers(16.4%) for FEV1.0, 8 workers(5.3%) for FEV1.0% and 37 workers(24.3%) for MMF, and significant increase by exposure duration was found in MMF. The distribution of workers who had ventilation impairment was as follows: 5 workers(3.8%) for obstructive type, 2 workers(l.5%) for restrictive type in the shielded arc welding group and, workers(4.6%) for obstructive type. 2 workers(l.3%) for restriotive type, and 1 worker(0.6%) was combined type of the CO2 arc welding group. In the respect of these results the significant pulmonary function and ventilatory impairment were observed in welding fume exposed workers who had not abnormal finding in chest X-ray, and MMF considered as the most sensitive pulmonary function index by welding fume exposure. Therefore even if it is hard to doing pulmonary function test in the first health examination of workers according to the Industrial Safety Health Act in the welding fume exposure workers. it is desirable to consider doing PFT. Also evaluating the ventilation impairment, it is necessary, to observe the change of MMF that marker of effort-independent portion.

• Keywords: welding fume exposed workerspulmonary function testpulmonary function and ventilatory impairment