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METHYL CHLOROFORM (1,1,1-TRICHLOROETHANE)†
| CAS # | 71-55-6 |
|---|---|
| Formula |
C₂H₃Cl₃ |
| Synonyms |
chlorothene; 1,1,1-trichloroethane; 1,1,1-trichloroethane (stabilized) |
| Physical description | Colorless liquid with a sweet, chloroform-like odor. | ||
|---|---|---|---|
| Boiling point | 165°F | Molecular weight | 133.4 |
| Freezing point/melting point | -26.5°F | Vapor pressure | 100 mmHg |
| Flash point | >200°F | Vapor density | 4.6 |
| Specific gravity | 1.31 | Ionization potential | 11.00 eV |
| Lower explosive limit (LEL) | 7.5% | Upper explosive limit (UEL) | 12.5% |
| NFPA health rating | 2 | NFPA fire rating | 1 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1720 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* |
|
| Sampling volume (TWA)* |
3 L |
| Sampling flow rate (TWA)* |
0.2 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | OSHA 14 (fully 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 | |||||
|---|---|---|---|---|---|
| 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 |
350 ppm (1900 mg/m³) |
REL-TWA |
|
TLV-TWA |
350 ppm [1992] |
PEL-TWA |
350 ppm (1900 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
450 ppm [1992] |
PEL-STEL |
450 ppm (2450 mg/m³) |
| PEL-C |
|
REL-C |
350 ppm (1900 mg/m³) [15 minutes] |
TLV-C |
|
PEL-C |
800 ppm |
| Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
Skin notation |
N |
| Notes: |
Notes:
|
Notes:
BEI® |
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
700 ppm |
|||||
| Carcinogenic classifications: IARC-3, TLV-A4, EPA-II |
Notes:
|
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
350 ppm/700 ppm/3500 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - 1,1,1-Trichloroethane NIOSH: Pocket Guide to Chemical Hazards - Methyl chloroform Literature References
|
Last Updated Date : 01/05/2021