TABLE III.

Percent Contribution by Size for Two Challenge Aerosols

Particle Size Range	NaCl Test Aerosol (%)A			DOP Test Aerosol (%)A
nm	Count	Mass	Scatter	Count	Mass	Scatter
0 – 100	68	8	0.6B*	10	0.3	<0.01B
100 – 200	26	31	8	47	11	2
200 – 300	4	26	20	28	25	12
300 – 400	1	15	25	10	24	24
400 – 500	0.2	9	23	3	17	28
500 – 600	0.07	5	13	1	10	19
600 – 700	0.02	3	7	0.4	6	10
700 – 800	<0.01	2	3	0.1	3	5
800 – 900	<0.01	1	0.7	0.05	2	1
900 – 1000	<0.01	0.6	0.3	0.02	1	0.4

^A.Columns may not add to 100% due to rounding error.

^B.Scatter values for 0 – 100 nm are theoretical; scatter from ultrafine particles is poorly detected by photometers