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METHYL CHLORIDE†
| CAS # | 74-87-3 |
|---|---|
| Formula |
CH₃Cl |
| Synonyms |
chloromethane; monochloromethane |
| Physical description | Colorless gas with a faint, sweet odor which is not noticeable at dangerous concentrations. | ||
|---|---|---|---|
| Boiling point | -12°F | Molecular weight | 50.5 |
| Freezing point/melting point | -144°F | Vapor pressure | 5.0 atm |
| Flash point | -49.0°F | Vapor density | 1.78 |
| Specific gravity | 0.997 at -11.2°F | Ionization potential | 11.28 eV |
| Lower explosive limit (LEL) | 8.1% | Upper explosive limit (UEL) | 17.4% |
| NFPA health rating | 2 | NFPA fire rating | 4 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1710 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | 2 CSC tubes in series (first tube 400/200 mg, second tube 100/50 mg) [SKC 226-09 & SKC 226-01] |
| Sampling time* |
|
| Sampling volume (TWA)* |
0.4-3 L |
| Sampling flow rate (TWA)* |
0.01-0.1 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | NIOSH 1001 (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 | Detector tube | Detector tube |
|---|---|---|
| Model/Type | Gastec 51 | Gastec 51L |
|
Sampling information (see manufacturer instructions) |
1 stroke, approx 10-480 ppm | 1 or 2 strokes, approx 1-86 ppm |
|
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 |
100 ppm (210 mg/m³) |
REL-TWA |
|
TLV-TWA |
50 ppm [1992] |
PEL-TWA |
50 ppm (105 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
100 ppm [1992] |
PEL-STEL |
100 ppm (210 mg/m³) |
| PEL-C |
200 ppm; 300 ppm (Peak - 5 min in any 3 hrs) |
REL-C |
|
TLV-C |
|
PEL-C |
300 ppm |
| Skin notation |
N |
Skin notation |
N |
Skin notation |
Y |
Skin notation |
N |
|
Notes:
Ceiling value applies only to OSHA General Industry standard. TWA applies to OSHA's General Industry and Maritime standards. See 29 CFR 1910.1000 Table Z-2 and 29 CFR 1915.1000 Table Z-Shipyards. |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 1.6 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens. |
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
2000 ppm |
|||||
| Carcinogenic classifications: IARC-3, NIOSH-Ca, TLV-A4, EPA-D; CBD |
Notes:
Ca |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
150 ppm/1000 ppm/3000 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methyl chloride NIOSH: Pocket Guide to Chemical Hazards - Methyl chloride Literature References
|
Last Updated Date : 01/29/2021