Table 3.

Evaluation of PM₁₀ calculated from number concentration by size measured by the OPC-N2 and PAS-1.108 based on: A) unknown aerosol type with density = 1000 kg/cm³; B) known aerosol type; C) OPC-N2 manufacturer recommended density of 1650 kg/cm³. Reference concentrations were calculated based on the known aerosol type.

Instrument		Data Pairs	Slope ± Std. Error	Intercept ± Std. Error (μg/m3)	r		R2	% Bias
A) Unknown aerosol type (density = 1000 kg/cm3)
Salt
OPC-N2		8	0.3 ± 0.006	-12 ± 5.9	0.991,2		0.99	-69
PAS-1.108		8	0.4 ± 0.008	-17 ± 7.6	0.991,2		0.99	-63
Welding fume
OPC-N2		7	0.05 ± 0.002	-5.6 ± 12	0.991,2		0.99	-89
PAS-1.108		7	0.08 ± 0.004	-33 ± 20	0.991,2		0.99	-88
ARD
OPC-N2		7	1.5 ± 0.07	163 ± 112	0.991,2		0.99	61
PAS-1.108		7	1.4 ± 0.03	73 ± 53	0.991,2		0.99	32
B) Known aerosol type
Salt (density = 2200 kg/cm3)
OPC-N2	8		0.7 ± 0.01	-26 ± 12	0.991,2	0.99		-41
PAS-1.108	8		0.8 ± 0.02	-38 ± 17	0.991,2	0.99		-29
Welding fume (density = 3400 kg/cm3)
OPC-N2		7	0.2 ± 0.008	-19 ± 39	0.991,2	0.99		-80
PAS-1.108		7	0.3 ± 0.01	-111 ± 69	0.991,2	0.99		-75
ARD (density = 2650 kg/cm3)
OPC-N2		7	3.9 ± 0.2	432 ± 299	0.991,2	0.99		323
PAS-1.108		7	3.6 ± 0.08	193 ± 141	0.991,2	0.99		248
C) Based on OPC-N2 manufacturer recommended density (density = 1650 kg/cm3)
Salt
OPC-N2		8	0.5 ± 0.01	-20 ± 9.7	0.991,2	0.99		-54
PAS-1.108		8	0.6 ± 0.01	-29 ± 12	0.991,2	0.99		-45
Welding fume
OPC-N2		7	0.08 ± 0.005	-13 ± 26	0.991,2	0.98		-92
PAS-1.108		7	0.1 ± 0.009	-62 ± 44	0.991,2	0.98		-89
ARD
OPC-N2		7	2.5 ± 0.1	269 ± 18	0.991,2	0.99		168
PAS-1.108		7	2.2 ± 0.05	120 ± 88	0.991,2	0.99		122

¹meets EPA criterion

²meets NOISH criterion