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2,4-TOLUENE-DIISOCYANATE†
| CAS # | 584-84-9 |
|---|---|
| Formula |
C₉H₆N₂O₂ |
| Synonyms |
2,4-diisocyanate-1-methylbenzene; TDI; 2,4-TDI; 2,4-toluene diisocyanate |
| Physical description | Colorless to pale-yellow solid or liquid (above 71°F) with a sharp, pungent odor. | ||
|---|---|---|---|
| Boiling point | 484°F | Molecular weight | 174.2 |
| Freezing point/melting point | 67.1-70.7°F | Vapor pressure | 0.01 mmHg at 77°F |
| Flash point | 270°F for an 80/20% 2,4/ 2,6 TDI mixture | Vapor density | 6 |
| Specific gravity | 1.2244 at 68°F | Ionization potential | |
| Lower explosive limit (LEL) | 0.9% | Upper explosive limit (UEL) | 9.5% |
| NFPA health rating | 3 | NFPA fire rating | 1 |
| NFPA reactivity rating | 2 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 2470 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | Isocyanate Sampling Filter Kit - GFF (37 mm, open-faced) coated with 1 mg 1-(2-pyridyl)piperazine [SLTC103] |
| Sampling time* |
15 min |
| Sampling volume (TWA)* |
15 L |
| Sampling flow rate (TWA)* |
1 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | UHPLC |
| Method reference | OSHA 5002 (fully validated) |
| Notes |
Refrigerate coated filters until used. Sample open-faced!! |
| Special requirements |
|
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media |
|
|---|---|
| Bulk Method |
|
| Device | Detector tube | Hazard Assessment Test Kit for Aromatic Isocyanates |
|---|---|---|
| Model/Type | Dräger - Toluene diisocyanate 0.02/a, 6724501 | 769-1002 |
|
Sampling information (see manufacturer instructions) |
25 strokes, approx 0.02-0.2 ppm range, uncertainty 30% | Isocyanate Surface and Dermal Sampling, Hazard Assessment Test Kit for Aromatic Isocyanates |
|
OSHA PEL
8-hour TWA (ST) STEL (C) Ceiling Peak |
NIOSH REL
Up to 10-hour TWA (ST) STEL (C) Ceiling |
ACGIH TLV©
8-hour TWA (ST) STEL (C) Ceiling |
|||||
|---|---|---|---|---|---|---|---|
| PEL-TWA |
|
REL-TWA |
|
TLV-TWA |
0.001 ppm (inhalable fraction and vapor) [2015] |
PEL-TWA |
0.005 ppm (0.04 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
0.005 ppm [2015] |
PEL-STEL |
|
| PEL-C |
0.02 ppm (0.14 mg/m³) |
REL-C |
|
TLV-C |
|
PEL-C |
0.02 ppm (0.15 mg/m³) |
| Skin notation |
N |
Skin notation |
N |
Skin notation |
Y |
Skin notation |
N |
| Notes: |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION. See Appendix A, NIOSH Potential Occupational Carcinogens |
Notes:
dermal sensitizer (DSEN), respiratory sensitizer (RSEN) |
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
2.5 ppm |
|||||
| Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R, TLV-A3 |
Notes:
Ca |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
0.01 ppm/0.15 ppm/0.6 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Toluene-2,4-diisocyanate NIOSH: Pocket Guide to Chemical Hazards - Toluene-2,4-diisocyanate Literature References
|
Last Updated Date : 04/02/2025