Table 1.
Dustiness of fine and nanoscale test powders at 50% relative humidity. Powders are grouped in material classes and then ranked by total dustiness.
| Powder | Total dustiness, D tot (%) | Respirable dustiness, D resp (%) | D resp/D tot | Specific surface area (m2/g) |
|---|---|---|---|---|
| Mean (SD) | Mean (SD) | |||
| Carbonaceous | ||||
| SWCNT | ||||
| HiPCO | 37.9 (3.4) | 31.8 (3.3) | 0.84 | 144c 508a |
| SWeNT | 8.1 | 3.3 | 0.41 | 617 (3)b |
| MWCNT | ||||
| Mitsui VII | 14.0 (4.3) | 2.4 (0.6) | 0.17 | 23 (0.5)b |
| CNF | ||||
| Pyrograph III | 4.9 (1.0) | 1.4 (0.3) | 0.28 | 57 (0.5)b |
| Carbon Black | ||||
| Printex 90 | 30.9 (3.1) | 12.9 (1.4) | 0.42 | 306 (4)b |
| Std. Ref. 8 | 0.8 (0.2) | 0.4 (0.1) | 0.46 | 139 a 143c |
| Sterling V | 0.3 (0.2) | 0.2 (0.1) | 0.61 | 37 (0.1)b |
| Fumed oxides | ||||
| SiO2 | ||||
| Aerosil 380 | 15.0 (3.0) | 5.5 (0.5) | 0.37 | 380d |
| Aerosil 200 | 7.8 (1.4) | 3.3 (0.5) | 0.42 | 200d |
| Aerosil 50 OX | 3.0 (0.1) | 1.5 (0.1) | 0.5 | 50 (15)d |
| Hydrophobic SiO2 | ||||
| Aerosil R812 | 22.1 (0.7) | 10.7 (0.4) | 0.49 | 300d |
| Aerosil R202 | 16.6 (4.6) | 6.2 (1.0) | 0.37 | 100 (20)d |
| Al2O3 | ||||
| Aeroxide Alu C | 26.0 (3.2) | 12.4 (2.1) | 0.48 | 100 (15)d |
| TiO2 | ||||
| Aeroxide P25 | 15.7 (5.1) | 7.2 (2.1) | 0.46 | 50 (15)d |
| CeO2 | ||||
| HSL CeO2 | 5.8 (0.2) | 2.8 (0.3) | 0.49 | 37 (9)d |
| Nanoscale metals | ||||
| Ni | 16.7 (0.4) | 7.5 (0.2) | 0.45 | 50 (15)d |
| Co | 7.2 (0.7) | 2.5 (0.2) | 0.35 | 45 (15)d |
| Mn | 4.2 (0.2) | 1.1 (0.1) | 0.27 | 28 (8)d |
| Ag | 1.7 (0.3) | 0.4 (0.2) | 0.25 | 20 (5)d |
| Fine oxides | ||||
| Lithium titanate spinel | 11.1 (1.1) | 3.4 (0.1) | 0.31 | 135d |
| AZ road dust (SiO2) | 7.7 (1.5) | 3.9 (0.8) | 0.5 | 8.0 (0.1)e |
| Microgrit CeO2 | 6.5 (2.2) | 2.6 (0.8) | 0.39 | 4.05 (0.01)e |
| Kemira TiO2 | 0.3 (0.5) | 0.1 (0.2) | 0.4 | 10d |
| Miscellaneous | ||||
| Microgrit SiC | 27.4 (1.0) | 9.6 (0.3) | 0.35 | 3.19 (0.02)e |
| Holland lactose | 5.2 (0.4) | 0.9 (0.1) | 0.17 | 0.534 (0.006)e |
| Nanoclays | ||||
| PGN | 3.9 (1.2) | 0.8 (0.3) | 0.21 | 11.29 (0.09)e |
| PGV | 3.6 (0.3) | 0.4 (0.1) | 0.10 | 34.52 (0.29)e |
Tabulated are materials tested, mean and standard deviations for both total and respirable dustiness. Dustiness is the ratio of collected to predispersed mass of powder for each test and expressed as a percentage. The D resp /D tot column provides the ratio of respirable to total dustiness and the final column, the specific surface area obtained by BET analysis for each material. SD, standard deviation.
b Pacific Surface Science, in Turkevich et al., in preparation.
c Pacific Surface Science, in Ruda-Eberenz et al. Ann. Occup. Hyg., in press.
d Manufacturer’s value.
e Pacific Surface Science, this work.