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METHYL IODIDE†
| CAS # | 74-88-4 |
|---|---|
| Formula |
CH₃I |
| Synonyms |
iodomethane; monoiodomethane |
| Physical description | Colorless liquid with a pungent, ether-like odor. | ||
|---|---|---|---|
| Boiling point | 109°F | Molecular weight | 141.94 |
| Freezing point/melting point | -88°F | Vapor pressure | 400 mmHg |
| Flash point | Vapor density | ||
| Specific gravity | 2.28 | Ionization potential | 9.54 eV |
| Lower explosive limit (LEL) | 10% | Upper explosive limit (UEL) | 15% |
| NFPA health rating | 3 | NFPA fire rating | 0 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1772 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | CSC tube (100/50 mg) [SKC 226-01] |
| Sampling time* |
|
| Sampling volume (TWA)* |
15-50 L |
| Sampling flow rate (TWA)* |
0.01-1 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FID |
| Method reference | NIOSH 1014 (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 | Detector tube |
|---|---|---|
| Model/Type | Miran 1A & 1B | Matheson-Kitagawa 8014-176S |
|
Sampling information (see manufacturer instructions) |
1.8 ppm@3.4µm | 5-40 ppm range |
|
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 |
5 ppm (28 mg/m³) |
REL-TWA |
2 ppm (10 mg/m³) |
TLV-TWA |
2 ppm [1978] |
PEL-TWA |
2 ppm (10 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
|
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
| Notes: |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 1.7 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens. |
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
100 ppm |
|||||
| Carcinogenic classifications: IARC-3, NIOSH-Ca |
Notes:
Ca |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
25 ppm/50 ppm/125 ppm |
|||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methyl iodide NIOSH: Pocket Guide to Chemical Hazards - Methyl iodide Literature References
|
Last Updated Date : 01/29/2021