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METHYL BROMIDE†
| CAS # | 74-83-9 |
|---|---|
| Formula |
CH₃Br |
| Synonyms |
bromomethane; monobromomethane |
| Physical description | Colorless gas with a chloroform-like odor at high concentrations. | ||
|---|---|---|---|
| Boiling point | 38°F | Molecular weight | 94.95 |
| Freezing point/melting point | -137°F | Vapor pressure | 1.9 atm |
| Flash point | Vapor density | 3.36 | |
| Specific gravity | 1.73 (liquid at 32°F) | Ionization potential | 10.54 eV |
| Lower explosive limit (LEL) | 10% | Upper explosive limit (UEL) | 16% |
| NFPA health rating | 3 | NFPA fire rating | 1 |
| NFPA reactivity rating | 0 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1680 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | 2 Anasorb 747 sampling tubes (6 mm glass tubes, the front tube contains 400 and the back 200 mg of sorbent) connected in series [SKC 226-82], tube holder [SKC 222-3L-1], Type D cover [SKC 224-29D] |
| Sampling time* | 60 min |
| Sampling volume (TWA)* | 3 L |
| Sampling flow rate (TWA)* |
0.05-0.2 L/min |
| Sampling volume (STEL/Peak/C)* |
3 L |
| Sampling flow rate (STEL/Peak/C)* |
0.05-0.2 L/min |
| Analytical method instruments | GC-FID |
| Method reference | OSHA PV2040 (partially validated) |
| Notes |
The Anasorb tubes should be separated and capped after sampling. Tubes should be refrigerated as soon after sampling as possible and shipped cold to the SLTC. |
| 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 136LA | Matheson-Kitagawa 8014-157SB |
|
Sampling information (see manufacturer instructions) |
1-2 strokes, 0.2-36 ppm range, uncertainty 16% for 1-6 ppm, 8% for 6-18 ppm | 1,2 or 4 strokes, approx 0.2-80 ppm rang |
|
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 |
1 ppm [1994] |
PEL-TWA |
1 ppm (3.88 mg/m³) |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
20 ppm (80 mg/m³) |
REL-C |
|
TLV-C |
|
PEL-C |
20 ppm |
| Skin notation |
Y |
Skin notation |
N |
Skin notation |
Y |
Skin notation |
Y |
| Notes: |
Notes:
CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 4.7 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens. See also Appendix G: 1989 Air Contaminants Update Project - Exposure Limits NOT in Effect |
Notes:
|
Notes:
|
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
250 ppm
|
|||||
| Carcinogenic classifications: IARC-3, NIOSH-Ca, TLV-A4, EPA-D |
Notes:
Ca |
||||||
|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
--/50 ppm/200 ppm |
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methyl bromide NIOSH: Pocket Guide to Chemical Hazards - Methyl bromide Literature References
|
Last Updated Date : 01/29/2021