Cobalt (Co) concentration in air (µg Co/m3) during full shift measurements (average 410 min) in hard metal industry
| Exposure group | n | Median | Range |
| Raw material | 11* | 5.6† | 0.82-24‡ |
| Sintered material | 8 | 0.13 | 0.012–0.55 |
| Final product | 9 | 0.14 | 0.026–0.45 |
*Two air samples were excluded from the result and further statistical analysis because workers used respiratory protection.
†Median significantly higher than median in other groups (p<0.001) using Wilcoxon rank-sum test.
‡Two samples were above the Swedish Occupational Exposure Limit Value, 20 µg Co/m3.