DYES, BENZIDINE-, o-TOLIDINE-, o-DIANISIDINE-: METHOD 5013, Issue 2, dated 15 August 1994 Page 5 of 5 TABLE 1. BENZIDINE- AND BENZIDINE-CONGENER-BASED DYES.
Color Index Name
C.I. Number
Molecular Formula
M.W.
Synonyms [4]
Range a µg per sampler µg/mb3 r
BENZIDINE-BASED: C.I. Direct Red 28
22120
C32H22N6S2O 6Na 2
696.67
Congo Red; CAS #573-58-0 RTECS QK1400000
27.3-273
546.5 -46
C.I. Direct Blue 6
22610
C32H20N6S4O 14Na 4
932
Amidine Blue 2B; CAS #2602-46-2 RTECS QJ6400000
15.0-300
30.6 -00
C.I. Direct Brown 95
30145
C31H18N6O 9Na 2Cu
759
Chrome Leather Brown; CAS #16071-86-6 RTECS GL7375000
24.3-242
486.4 -85
C.I. Direct Black 38
30235
C34H25N9S2O 7Na 2
781
Amidine Black GA; CAS #1937-37-7 RTECS QJ6160000
12.5-250
250.5 -00
o-TOLIDINE-BASED: C.I. Direct Red 2
23500
C34H26N6S2O 6Na 2
724.74
Benzopurpurine 4B; CAS #992-59-6 RTECS QK1765000
16.7-334
334.6 -68
24140
C34H24N4S2O 10Na 2
758.69
Direct Azurine G; Benzo Azurine G; CAS #2429-71-2
10.2-204
204.4 -08
o-DIANISIDINE-BASED: C.I. Direct Blue 8 a b
Air concentrations calculated from analytical results with an air volume of 500 L assumed. The letters "A" and "B" refer to the reduction buffer solutions described in the REAGENTS section, items 11.a and b.
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
