Mean estimate per occupation group (µg/m3 EC prediction for a gold mine in 2011), based on 12 hour shifts
| EC† exposure levels in 2011 (µg/m3) | ||
|---|---|---|
| Occupation group* | Group GM‡ (95% CI) | Job-specific§ GMs min–max |
| Surface workers | ||
| S1 | 13 (10 to 17) | 10–19 |
| S2 | 13 (8 to 23) | 11–17 |
| S3 | 15 (9 to 25) | 11–17 |
| S4 | 14 (7 to 26) | 12–17 |
| S5 | 13 (8 to 23) | 13–15 |
| Underground workers | ||
| UG1 | 44 (25 to 75) | 31–53 |
| UG2 | 37 (22 to 63) | 33–45 |
| UG3 | 37 (22 to 63) | 25–59 |
| UG4 | 37 (22 to 63) | 25–55 |
| UG5 | 18 (10 to 32) | 14–24 |
*Occupation groups as listed in the Methods section, under ‘Occupational grouping’.
†Elemental carbon.
‡Geometric mean.
§Job-specific GMs have been derived using the model function, including the best linear unbiased prediction estimates as presented in online supplementary table S1.
EC, elemental carbon; GM, geometric mean.