NIOSH Pocket Guide to Chemical Hazards


CAS 334-88-3


RTECS PA7000000
Synonyms & Trade Names
Azimethylene, Azomethylene, Diazirine
DOT ID & Guide


NIOSH REL: TWA 0.2 ppm (0.4 mg/m3)
OSHA PEL: TWA 0.2 ppm (0.4 mg/m3)
IDLH 2 ppm See: 334883 Conversion 1 ppm = 1.72 mg/m3
Physical Description
Yellow gas with a musty odor. [Note: Shipped as a liquefied compressed gas.]
MW: 42.1
BP: -9°F
FRZ: -229°F
Sol: Reacts
VP: >1 atm
IP: 9.00 eV
RGasD: 1.45

Fl.P: NA (Gas)
UEL: ?
LEL: ?

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.]
Measurement Methods
NIOSH 2515
See: NMAM or OSHA Methods
Personal Protection & Sanitation (See protection)
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

Important additional information about respirator selection
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
(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
Exposure Routes inhalation, skin and/or eye contact (liquid)
Symptoms Irritation eyes; cough, shortness breath; headache, lassitude (weakness, exhaustion); flush skin, fever; chest pain, pulmonary edema, pneumonitis; asthma; liquid: frostbite
Target Organs Eyes, respiratory system
See also: INTRODUCTION   See ICSC CARD: 1256   See MEDICAL TESTS: 0068