Exposure in the four occupational groups
| Average exposure | Alpine train drivers (μT) | Lowland train drivers (μT) | Shunting yard engineers (μT) | Train attendants (μT) | Station masters (μT) |
|---|---|---|---|---|---|
| In 1940 | 54.9 | 17.2 | 3.6 | 1.1 | 0.3 |
| In 1960 | 24.5 | 18.4 | 5.2 | 1.7 | 0.5 |
| In 1980 | 21.4 | 21.4 | 5.5 | 1.8 | 0.7 |
| In 2000 | 21.0 | 21.0 | 6.0 | 4.2 | 1.0 |