Table 1.
Exposure concentration levels of respirable dust, quartz and cristobalite
| Aerosol concentration levels | N | AM | Median | SD | GM | GSD | Min | Max |
|---|---|---|---|---|---|---|---|---|
| Exposure measurements | ||||||||
| Respirable dust (mg/m3) | 85 | 0.85 | 0.35 | 1.6 | 0.39 | 3.1 | 0.062 | 9.7 |
| Respirable quartz (mg/m3) | 85 | 0.052 | 0.018 | 0.11 | 0.016 | 4.4 | 0.0013 | 0.61 |
| Respirable cristobalite (mg/m3) | 85 | 0.0037 | 0.0034 | 0.0015 | 0.0035 | 1.3 | 0.0028 | 0.014 |
| Stationary measurements | ||||||||
| Inhalable dust (mg/m3) | 36 | 3.2 | 2.3 | 3.9 | 1.6 | 3.9 | 0.045 | 16 |
| Total dust (mg/m3) | 36 | 3.4 | 2.2 | 4.3 | 1.5 | 4.4 | 0.078 | 16 |
| Respirable dust (mg/m3) | 36 | 0.58 | 0.36 | 0.58 | 0.32 | 3.3 | 0.058 | 1.9 |
| Respirable quartz (mg/m3) | 36 | 0.026 | 0.011 | 0.37 | 0.031 | 6.8 | 0.0012 | 0.26 |
| Respirable cristobalite (mg/m3) | 36 | 0.0034 | 0.0031 | 0.00096 | 0.0033 | 1.2 | 0.0029 | 0.0072 |
| PM10 (mg/m3) | 36 | 1.9 | 1.6 | 1.9 | 1.1 | 3.1 | 0.15 | 8.7 |
| PM2.5 (mg/m3) | 36 | 1.2 | 0.57 | 1.9 | 0.63 | 3.1 | 0.085 | 11 |
| PM1.0 (mg/m3)a | 35 | 0.35 | 0.2 | 0.41 | 0.27 | 3.7 | 0.018 | 1.7 |
| Total particle area (A-trak) (µm2/cm3) | 34 | 420 | 140 | 540 | 160 | 4.7 | 9.2 | 1900 |
| Particle number ((P-trak)/cm3) | 36 | 78,000 | 43,000 | 91,000 | 32,000 | 4.7 | 1500 | 360,000 |
Stationary concentration levels of inhalable, total and respirable dust, respirable quartz and cristobalite, PM10, PM2.5, PM1.0, particle surface area (A-trak) and particle number (P-trak)
N number of measurements, AM arithmetic mean, SD standard deviation, GM geometric mean, GSD geometric standard deviation
aDusttrak