METHYL BROMIDE†

Chemical Identification
Chemical Identification
CAS # 74-83-9
Formula

CH₃Br

Synonyms

bromomethane; monobromomethane

Physical Properties
Physical Properties
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
Monitoring Methods Used by OSHA
Monitoring Methods Used by OSHA
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]
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 Method
Wipe Method
Sampler/Sampling media
 

 

Bulk Method
Bulk Method
 

 

On-Site Screening Techniques
On-Site Screening Techniques
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
Exposure Limits
Exposure Limits
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
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
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:
 
 

See 29 CFR 1910.1000 Table Z-1.

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

Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methyl bromide

NIOSH: Pocket Guide to Chemical Hazards - Methyl bromide

Literature References

 
 
  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methyl bromide. See annual publication for most recent information.
  • International Chemical Safety Cards (WHO/IPCS/ILO): Methyl Bromide.
  • EPA Air Toxics Website: Methyl Bromide (Bromomethane). U.S. Environmental Protection Agency Technology Transfer Network.
  • Garnier, R., Rambourg-Schepens, M.O., Muller, A. and Hallier, E.: Glutathione transferase activity and formation of macromolecular adducts in two cases of acute methyl bromide poisoning. Occup. Environ. Med. 53(3): 211-215, 1996.
  • Lenhart, S.W. and Gagnon, Y.T.: Health hazard evaluation of methyl bromide soil fumigations. Appl. Occup. Environ. Med. 14(7): 407-412, 1999.
  • No authors: Methyl bromide. IARC Monogr. Eval. Carcinog. Risks Hum. 71(Pt. 2): 721-735, 1999.
  • Pohanish, R.P. (editor): Methyl Bromide. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1531-1534.

Last Updated Date : 01/29/2021