| Spirometric Parameters | Control N = 43 | Welders N = 32 | p |
| FVC (L) | 4.79 ± 0.44 [3.73; 5.43] | 4.15 ± 0.69 [2.24; 5.67] | 3.5 × 10−5 |
| FVC % predicted | 112.2 ± 11.11 [82.0; 137.0] | 92.35± 18.01 [40.8; 141.5] | 1.4 × 10−6 |
| FEV1 (L) | 4.27 ± 0.412 [3.33; 5.15] | 3.69 ± 0.39 [2.77; 4.51] | 4.1 × 10−8 |
| FEV1 % predicted | 120.3 ± 11.15 [90.0; 142.0] | 97.75 ± 13.04 [65.5; 127.5] | 8.05 × 10−11 |
| FEV1/FVC (%) | 89.14 ± 4.77 [79.05; 100.0] | 87.02 ± 6.51 [72.1; 98.5] | 0.12 |
| MMEF (L) | 5.17 ± 1.15 [3.44; 9.23] | 4.38 ± 0.92 [2.37; 6.53] | 0.001 |
| MMEF % predicted | 135 ± 30.5 [87; 251] | 97.73 ± 24.79 [47.8; 156.5] | 1.4 × 10−7 |