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1,1-DIMETHYLHYDRAZINE†
| CAS # | 57-14-7 |
|---|---|
| Formula |
C₂H₈N₂ |
| Synonyms |
dimazine; DMH; UDMH; unsymmetrical dimethylhydrazine |
| Physical description | Colorless liquid with an ammonia- or fish-like odor. | ||
|---|---|---|---|
| Boiling point | 147°F | Molecular weight | 60.1 |
| Freezing point/melting point | -72°F | Vapor pressure | 103 mmHg |
| Flash point | 5°F | Vapor density | 1.94 |
| Specific gravity | 0.79 | Ionization potential | 8.05 eV |
| Lower explosive limit (LEL) | 2% | Upper explosive limit (UEL) | 95% |
| NFPA health rating | 4 | NFPA fire rating | 3 |
| NFPA reactivity rating | 1 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 0940 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | Bubbler (0.1 M hydrochloric acid) |
| Sampling time* | |
| Sampling volume (TWA)* | 2-100 L |
| Sampling flow rate (TWA)* | 0.2-1 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | UV-VIS |
| Method reference | NIOSH 3515 (partially validated) |
| Notes | |
| 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 | Infrared spectrophotometer |
|---|---|
| Model/Type | Miran 1A & 1B |
|
Sampling information (see manufacturer instructions) |
0.3 ppm@11.2 µm |
|
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 |
0.5 ppm (1 mg/m³) |
REL-TWA |
|
TLV-TWA |
0.01 ppm [1993] |
PEL-TWA |
0.01 ppm (0.025 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
|
REL-C |
0.06 ppm (0.15 mg/m³) [120 minutes] |
TLV-C |
|
PEL-C |
|
| Skin notation |
Y |
Skin notation |
N |
Skin notation |
Y |
Skin notation |
Y |
| Notes: |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION. See Appendix A. |
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
15 ppm |
|||||
| Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R, TLV-A3 |
Notes:
Ca |
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|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
|
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - 1,1-Dimethylhydrazine NIOSH: Pocket Guide to Chemical Hazards - 1,1-Dimethylhydrazine Literature References
|
Last Updated Date : 01/15/2021