Table 1.
Number of samples and GM and geometric standard deviation (GSD) of wood dust exposure levels, overall and stratified by level of selected categorical variables.
| Variable | N a | %b | ND (n)c | GM (mg m−3)d | GSDe |
|---|---|---|---|---|---|
| Overall | 5170 | 100 | 127 | 1.64 | 4.3 |
| Sample type | |||||
| Area | 1451 | 28.1 | 50 | 1.04 | 4.0 |
| Personal | 3719 | 71.9 | 77 | 1.96 | 4.3 |
| Province | |||||
| British Columbia | 1829 | 35.4 | 67 | 0.92 | 4.2 |
| Ontario | 3341 | 64.6 | 60 | 2.25 | 3.9 |
| CANJEM period | |||||
| 1970–1984 | 678 | 13.1 | 36 | 1.21 | 5.2 |
| 1985–2005 | 4492 | 86.9 | 91 | 1.71 | 4.2 |
ND = non-detected.
aNumber of samples.
bRelative percentage of samples by level.
cNumber of non-detected samples.
dComputed with the robust Regression on order statistics (ROS) method for non-detects (Helsel, 2012).
eComputed with the robust ROS method.