ISOCYANAT ES, TOTA L (MAP): METHO D 5525, Issue 1, dated 15 March 2003 - Page 12 of 17 TABLE 1. EXPOSURE LIMITS, PROPERTIES, CAS AND RTECS NUMBERS Isocyanates
Expo sure Limits µg /m 3*
Properties [11]
OSHA
NIOSH
AC GIH
(PEL)
(REL)
(TLV)
Toluene 2,6-diisocyanate (2,6-TDI)
no PEL
lowest feasible (Ca)
liquid; d 1.225 g/mL @ 25oC; MP no TLV 19.5-21.5/C; VP 3.33 Pa (0.025 mm Hg) @ 25oC [12]
Toluene 2,4-diisocyanate (2,4-TDI)
liquid; d 1.214 g/mL @ 25oC; MP 20lowest 22oC, VP 3.33 Pa (0.025 mm Hg) @ feasible 36 140 (Ca) 140 STEL 25oC [12] (ceiling)
4,4'-Methylenebis(phenyl isocyanate) (MDI)
50; 200 200 (10 min (ceiling) ceiling)
51
34
no PEL
35; 140 (10 min ceiling)
Isophorone diisocyanate (IPDI)
45
no PEL
45; 180 (10 min ceiling)
4,4'-Methylenebis(cyclohexyl isocyanate) (HMDI)
No REL; 110 (10 min no PEL ceiling)
1,6-Hexamethylene diisocyanate (HDI)
1,5-Naphthalene diisocyanate (NDI)
no PEL
40;70 (10 min ceiling)
54
CAS #
RTECS #
91-08-7
CZ6310000
584-84-9
CZ6300000
solid (fused); d 1.180g/mL @ 25oC; MP 42-44oC; VP 6x10-4 Pa (4.5x10-6 mm Hg) @ 25oC [12]
101-68-8 NQ9350000
liquid; d 1.04 g/mL @ 25oC; BP 255oC; 7 Pa (0.05 mm Hg) @ 25oC [13]
822-06-0 MO1740000
liquid; mixture of isomers, d 1.049 @ 25oC; MP -60oC [14]; VP 0.04 Pa @ 20oC (0.0003 mm Hg) [12] 4098-71-9 NQ9370000
liquid; mixture of isomers, d 1.066 g/mL @ 25oC; VP 0.13 Pa @ 20oC (0.001 mm Hg) [15]
5124-30-1 NQ9250000
solid flakes; MP 129-131oC [12]; VP 0.4 Pa @ 25oC (0.003 mm Hg) [12]
3173-72-6 NQ9600000
no TLV
1 ppb = 7.1 2 µg /m 3 TD I, 10.24 µg/m 3 MD I, 6.88 µ g/m 3 HD I, 9.09 µ g/m 3 IPD I, 10.73 µg/m 3 HM DI, 8.60 µg/m 3 NDI
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition
