Respirable dust exposures among the different job categories (mean (SD))
| Job categories | Respirable dust (mg/m3) | Iron in respirable dust (μg/m3) | Manganese in respirable dust (μg/m3) |
| Furnace | 20.47 (1.14) | 254.70 (120.13) | 10.89 (12.95) |
| Continuous casting | 6.58 (0.19) | 703.22 (81.41) | 28.63 (0.51) |
| Rolling mill | 21.82 (1.71) | 251.24 (129.93) | 10.27 (10.97) |
| Mechanical workshop | 3.66 (0.29) | 242.25 (160.67) | 9.67 (7.84) |
| Fabrication workshop | 21.89 (1.38) | 342.34 (115.04) | 19.44 (10.06) |
| General works | 20.37 (1.19) | 243.62 (123.16) | 10.52 (12.73) |
| Exposed workers | 16.53 (7.25)3-150 | 339.56 (182.17) | 14.90 (7.66) |
| Unexposed workers | 0.26 (0.07)3-150 | ND | ND |
ND=Not detected.
↵3-150 p<0.0001, analysis of variance (ANOVA).