Calculation of a worker's fibre years of exposure using ASTEM
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Job | Employment period | Task | Task duration | Job duration (years) | Exposure (% shift) | Period of exposure | Matrix level (f/ml) | Fibre years | Total fibre years |
| ×=×= | |||||||||
| Carpenter constructing fibro cottages working a 40 h week | 1971–1975 | Cutting asbestos cement sheets | 2 h per day | 4 | 2/8 | 1 | 5.2 | 5.2 | |
| Drilling asbestos sheets | 0.5 h per day | 4 | 0.5/8 | 0.25 | 2.7 | 0.675 | |||
| Sweeping up worksite | 1 h per fortnight | 4 | 1/80 | 0.05 | 6 | 0.3 | 6.2 | ||
ASTEM, asbestos-specific exposure matrix.