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METHYL HYDRAZINE (MONOMETHYL HYDRAZINE)†
| CAS # | 60-34-4 |
|---|---|
| Formula |
CH₆N₂ |
| Synonyms |
MMH; monomethylhydrazine |
| Physical description | Fuming, colorless liquid with an ammonia-like odor. | ||
|---|---|---|---|
| Boiling point | 190°F | Molecular weight | 46.07 |
| Freezing point/melting point | -62.3°F | Vapor pressure | 38 mmHg |
| Flash point | 70°F | Vapor density | 1.6 |
| Specific gravity | 0.874 at 77°F | Ionization potential | 8.00 eV |
| Lower explosive limit (LEL) | 2.5% | Upper explosive limit (UEL) | 97% |
| NFPA health rating | 4 | NFPA fire rating | 3 |
| NFPA reactivity rating | 2 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1794 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | 2 GFFs (37 mm) coated with sulfuric acid, in 3-piece cassette, separated by the ring section [SKC 225-9004] |
| Sampling time* | |
| Sampling volume (TWA)* | 240 L |
| Sampling flow rate (TWA)* | 1 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | HPLC |
| Method reference | OSHA 108 (fully validated) |
| Notes | The 2 filters are separated by the ring section of the 3-piece cassette to provide a backup portion to the sampling train. |
| 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 | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
|
Sampling information (see manufacturer instructions) |
|
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 |
0.01 ppm [1991] |
PEL-TWA |
0.01 ppm (0.019 mg/m³) |
||
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C |
0.2 ppm (0.35 mg/m³) |
REL-C |
0.04 ppm (0.08 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, NIOSH Potential Occupational Carcinogens. |
Notes: | Notes: | ||||
| Health factors: See NIH-NLM PubChem. | IDLH |
20 ppm |
|||||
| Carcinogenic classifications: NIOSH-Ca, TLV-A3 |
Notes:
Ca |
||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methylhydrazine NIOSH: Pocket Guide to Chemical Hazards - Methyl hydrazine Literature References
|
Last Updated Date : 01/22/2024