The objective of this study was to evaluate the concentration and size-distribution of respirable crystalline silica among concrete finishers in the construction industry.Methods
Active-specific personal air sampling(n=129) were carried out in eight apartment complex construction sites by using PVC(poly vinyl chloride) filters with aluminium cyclones(flow rate at 2.5Lpm). Crystalline silica was analysed by FTIR(Fourier-transform infrared spectroscopy). The concentration of crystalline silica were showed by three different types of construction jobs(concrete chipping, grinding, plastering) and four different workplace(exterior wall, inside of apartment unit, staircase, underground parking lot).Results
The concentration of respirable crystalline silica was highest in concrete grinding(2.058 mg/m3) followed by concrete chipping(0.123 mg/m3), and plastering work(0.003 mg/m3). Concentration of crystalline silica was differ by the types of workplace in concrete grinding work, the concentration of respirable crystalline silica in staircase shows highest concentration(4.177 mg/m3) followed by inside of apartment unit(2.761 mg/m3), underground parking lot(1.302 mg/m3), and exterior wall(0.893 mg/m3). Considering the proportion of crystalline silica in the dust from job type, crystalline silica content was higher for concrete chipping work. The crystalline silica content was 6.921% in chipping work, 4.121% in grinding and 0.943 in plastering work. The correlation factors between respirable crystalline silica and respirable dust was 0.970 (p<0.01) in chipping work, 0.793 (p<0.01) in grinding and 0.100 (p=0.568) in plastering work.