Table 3.

Potential determinants of exposure to respirable and inhalable welding fume (excluding users of PAPRs).

Factor	Respirable, n = 215				Inhalable (GSP), n = 177
	n	n <LOD a	$\text{Exp}\left(\hat{\beta }\right)$	95% CI	n	n <LOD a	$\mathrm{Exp}\left(\hat{\beta }\right)$	95% CI
Intercept (mg m−3)			2.72	2.12–3.49			4.02	3.11–5.20
Gas metal arc welding	78	9	1		62	2	1
FCAW	42	0	2.25	1.52–3.32	22	0	1.68	1.10–2.58
TIG	66	47	0.18	0.12–0.27	64	22	0.19	0.13–0.29
Shielded metal arc welding	17	8	0.68	0.37–1.26	17	3	0.78	0.46–1.34
Miscellaneous	12	1	1.13	0.61–2.10	12	0	1.93	0.53–1.62
Mild steel	83	5	1		59	0	1
Stainless steel	122	58	0.55	0.39–0.79	108	25	0.74	0.50–0.10
Miscellaneous	10	2	0.83	0.43–1.58	10	2	1.19	0.66–2.17
Nonconfined space	193	65	1		165	27	1
Confined space	22	0	1.87	1.17–2.99	12	0	1.37	0.81–2.29
Nonefficient LEV	167	47	1		130	20	1
Efficient LEV	48	18	0.43	0.29–0.64	47	7	0.45	0.32–0.64
R 2 (95% CI)			0.65b (0.57–0.73)				0.59b (0.49–0.68)

^a N _<LOD, number of observations below the limit of determination.

^b R ² (Harel, 2009).