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Methyl bromide

Synonyms & Trade Names
Bromomethane, Monobromomethane
CAS No.
74-83-9
RTECS No.
PA4900000
DOT ID & Guide
1062 123
Formula
CH3Br
Conversion
1 ppm = 3.89 mg/m3
IDLH
Ca [250 ppm]
See: 74839
Exposure Limits
NIOSH REL
: Ca See Appendix A
OSHA PEL
†: C 20 ppm (80 mg/m3) [skin]
Measurement Methods

NIOSH 2520;
OSHA PV2040
See: NMAM or OSHA Methods
Physical Description
Colorless gas with a chloroform-like odor at high concentrations. [Note: A liquid below 38°F. Shipped as a liquefied compressed gas.]
MW:
95.0
BP:
38°F
FRZ:
-137°F
Sol:
2%
VP:
1.9 atm
IP:
10.54 eV
Sp.Gr:
1.73 (Liquid at 32°F)
Fl.P:
NA (Gas)
UEL:
16.0%
LEL:
10%
RGasD:
3.36
Flammable Gas, but only in presence of a high energy ignition source.
Incompatibilities & Reactivities
Aluminum, magnesium, strong oxidizers [Note: Attacks aluminum to form aluminum trimethyl, which is SPONTANEOUSLY flammable.]
Exposure Routes
inhalation, skin absorption (liquid), skin and/or eye contact (liquid)
Symptoms
irritation eyes, skin, respiratory system; muscle weak, incoordination, visual disturbance, dizziness; nausea, vomiting, headache; malaise (vague feeling of discomfort); hand tremor; convulsions; dyspnea (breathing difficulty); skin vesiculation; liquid: frostbite; [potential occupational carcinogen]
Target Organs
Eyes, skin, respiratory system, central nervous system
Cancer Site
[in animals: lung, kidney & forestomach tumors]
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact (liquid)
Eyes: Prevent eye contact (liquid)
Wash skin: When contaminated (liquid)
Remove: When wet (flammable)
Change: No recommendation
Provide: Quick drench (liquid)
First Aid
(See procedures)
Eye: Irrigate immediately (liquid)
Skin: Water flush immediately (liquid)
Breathing: Respiratory support
Respirator Recommendations

NIOSH

At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0109   See MEDICAL TESTS: 0138
 

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