# NIOSH Pocket Guide to Chemical Hazards
Diazomethane | CAS 334-88-3
CH2N2 | RTECS PA7000000
Synonyms & Trade Names Azimethylene, Azomethylene, Diazirine | DOT ID & Guide
Exposure Limits | NIOSH REL: TWA 0.2 ppm (0.4 mg/m3)
OSHA PEL: TWA 0.2 ppm (0.4 mg/m3)
IDLH 2 ppm | 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
Personal Protection & Sanitation Skin: Frostbite Eyes: Frostbite Wash skin: No recommendation Remove: When wet (flammable) Change: No recommendation Provide: Frostbite | 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
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