Table 3.

BZCs (μg m⁻³) of monomeric and polymeric HDI^a for samples collected in NC and WA stratified by sampler type

Analyte	NC				WA
	Nb	GM	GSD	Range	Nb	GM	GSD	Range
HDI	88	3.21	6.05	0.003–179	200	4.56	5.10	0.0007–65.5
One stage	19	1.54	5.26	0.003–10.7	78	9.49	2.96	0.009–60.3
Two stage	69	3.93	6.00	0.01–179	122	2.85	5.79	0.0007–65.5
Uretidone	88	1.68	27.2	0.002–1430	200	2.35	15.2	0.0004–613
One stage	19	0.84	7.29	0.002–62.6	78	7.02	11.8	0.004–613
Two stage	69	2.04	33.9	0.003–1430	122	1.16	13.8	0.0004–266
Biuret	88	2.58	11.4	0.01–7720	200	12.8	12.4	0.003–1020
One stage	19	3.17	6.07	0.08–70.0	78	24.3	8.22	0.03–1020
Two stage	69	2.44	13.7	0.01–7720	122	8.5	15.3	0.003–734
Isocyanurate	88	958	6.05	4.09–17 800	200	1670	3.96	0.09–18 700
One stage	19	825	4.74	17.8–3190	78	2160	3.67	0.68–18 700
Two stage	69	1000	6.48	4.09–17 800	122	1420	4.06	0.09–14 600

GSD, geometric standard deviation.

^aMultiple imputation (n = 10 imputed datasets) was used to impute air-sampling data below detection limits.

^bNumber of measurements representing the TWA recorded for each paint task. Because of sampling pump malfunction, seven samples collected in NC and one sample collected in WA were excluded.