Table 2 Exposure characteristics of miners (n = 357)
Characteristics | Mine 1 (n = 137) | Mine 2 (n = 99) | Mine 3 (n = 121) |
|---|---|---|---|
Length of service, years, Mean (SD) (Range) | 5.2 (2.7) (1.0–13.1) | 5.0 (2.5) (1.1–11.4) | 5.2 (2.3) (1.2–11.0) |
Overall respirable silica dust mg/m3, Median (Range) | 0.4 (0.0–1.0) | 0.2 (0.1–1.3) | 0.2 (0.1–0.5) |
Silica dust in sections mg/m3, Median (Range) | |||
Crusher Attend | 0.6 (0.1–1.0) | 0.3 (0.1–0.9) | 0.3 (0.1–0.5) |
Blasting Tech/Foreman | 0.5 (0.2–0.9) | 0.4 (0.1–1.1) | 0.3 (0.1–0.4) |
Lasher | 0.4 (0.0–1.0) | 0.2 (0.1–1.0) | 0.2 (0.1–0.4) |
Driller | 0.4 (0.2–0.9) | 0.2 (0.1–0.9) | 0.2 (0.1–0.5) |
Trammer | 0.4 (0.2–0.8) | 0.3 (0.1–1.3) | 0.2 (0.1–0.4) |
W/shop foreman/Attend | 0.4 (0.1–0.7) | 0.2 (0.1–0.6) | 0.2 (0.1–0.4) |
Others-workman | 0.4 (0.1–0.9) | 0.2 (0.1–1.0) | 0.2 (0.1–0.4) |
Cumulative respirable silica dust mg.y/m3, Mean (SD) (Range) | 1.3 (0.7) (0.3–3.2) | 1.1 (0.5) (0.3–2.2) | 2.3 (1.0) (0.7–4.7) |