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Diazomethane

Synonyms & Trade Names
Azimethylene, Azomethylene, Diazirine
CAS No.
334-88-3
RTECS No.
DOT ID & Guide
Formula
CH₂N₂
Conversion
1 ppm = 1.72 mg/m3
IDLH
2 ppm
See: 334883
Exposure Limits
NIOSH REL
TWA 0.2 ppm (0.4 mg/m3)
OSHA PEL
TWA 0.2 ppm (0.4 mg/m3)
Measurement Methods
NIOSH 2515
See: NMAM or OSHA Methods
Physical Description
Yellow gas with a musty odor. [Note: Shipped as a liquefied compressed gas.]
Molecular Weight
42.1
Boiling Point
-9°F
Freezing Point
-229°F
Solubility
Reacts
Vapor Pressure
>1 atm
Ionization Potential
9.00 eV
Flash Point
NA (Gas)
Upper Explosive Limit
?
Lower Explosive Limit
?
Relative Gas Density
1.45
Flammable Gas [EXPLOSIVE!]
Incompatibilities & Reactivities
Alkali metals, water, drying agents such as calcium arsenate [Note: May explode violently on heating, exposure to sunlight, or contact with rough edges such as ground glass.]
Exposure Routes
inhalation, skin and/or eye contact (liquid)
Symptoms
irritation eyes; cough, short breath; headache, lassitude (weakness, exhaustion); flush skin, fever; chest pain, pulmonary edema, pneumonitis; asthma; liquid: frostbite
Target Organs
Eyes, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:Frostbite
Eyes:Frostbite
Wash skin:No recommendation
Remove:When wet (flammable)
Change:No recommendation
Provide:Frostbite wash
First Aid
(See procedures)
Eye:Frostbite
Skin:Frostbite
Breathing:Respiratory support
Respirator Recommendations

NIOSH/OSHA

Up to 2 ppm:
(APF = 10) Any supplied-air respirator*
(APF = 50) Any self-contained breathing apparatus with a full facepiece

Emergency or planned entry into unknown concentrations or IDLH conditions:
(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   ICSC CARD: 1256   MEDICAL TESTS: 0068
Page last reviewed: October 30, 2019