Table 5.
Airborne manganese mass concentrations of all size fractions and MMADs by work area using eight-stage impactor samplers placed in breathing zones of workers
| Facility | Work area | n | GM (μg/m3) | GSD | Range (μg/m3) | MMAD (μm) AM (SD) |
|---|---|---|---|---|---|---|
| Shipbuilding yard | Steel cutting | 10 | 109.5 | 3.4 | 9.1–571.2 | 15.31 (2.12) |
| Block assembly | 32 | 323.0 | 4.4 | 4.2–2,467.6 | 0.22 (0.05) | |
| Block erection | 21 | 193.2 | 5.2 | 6.8–3,141.8 | 0.23 (0.06) | |
| Outfitting preparation | 7 | 55.8 | 3.7 | 3.6–165.2 | 0.31 (0.03) | |
| Outfitting installation | 16 | 186.0 | 3.9 | 16.4–1,862.1 | 0.21 (0.03) | |
| Total | 86 | 196.5 | 4.6 | 3.6–3,141.8 | 0.36 (0.25) | |
AM, arithmetic mean; GM, geometric mean; GSD, geometric standard deviation; MMAD, mass median aerodynamic diameter; n, number of samples; SD, standard deviation.