International Chemical Safety Cards DIAZOMETHANE ICSC: 1256 Azimethylene Diazirine CH2N2 Molecular mass: 42.04 ICSC #    1256 CAS #     334-88-3 RTECS # PA7000000 EC #         006-068-00-8 March 15, 1995 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Extremely flammable. Many reactions may cause fire or explosion. Gives off irritating or toxic fumes (or gases) in a fire. NO open flames, NO sparks, and NO smoking. Shut off supply; if not possible and no risk to surroundings, let the fire burn itself out; in other cases extinguish with powder, carbon dioxide. EXPLOSION Gas/air mixtures are explosive. Closed system, ventilation, explosion-proof electrical equipment and lighting. Do NOT expose to friction or shock. Prevent build-up of electrostatic charges (e.g., by grounding). Combat fire from a sheltered position. EXPOSURE AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR!  •INHALATION Headache. Laboured breathing. Shortness of breath. Sore throat. Vomiting. Malaise. Symptoms may be delayed (see Notes). Ventilation, local exhaust, or breathing protection. Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer for medical attention.  •SKIN Redness. Burning sensation. Pain. Serious frostbite. Cold-insulating gloves. ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer for medical attention. Wear protective gloves when administering first aid.  •EYES Redness. Pain. Face shield or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Do not eat, drink, or smoke during work. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Evacuate danger area! Consult an expert! Ventilation. Personal protection: complete protective clothing including self-contained breathing apparatus. Solutions of diazomethane should not be stored (see Notes). T symbol R: 45 S: 53-45 SEE IMPORTANT INFORMATION ON BACK ICSC: 1256 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities (C) IPCS CEC 1994. No modifications to the International version have been made except to add the OSHA PELs, NIOSH RELs and NIOSH IDLH values.

International Chemical Safety Cards DIAZOMETHANE ICSC: 1256 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: YELLOW GAS. PHYSICAL DANGERS: The gas is heavier than air and may travel along the ground; distant ignition possible. CHEMICAL DANGERS: May explosively decompose on shock, friction, or concussion. May explode on heating at 100°C, or on contact with rough surfaces or if impurities or solids are present in the undiluted liquid or in the concentrated solutions, or under high intensity lighting. Contact with alkali metals and calcium sulfate causes explosions. OCCUPATIONAL EXPOSURE LIMITS: TLV: 0.2 ppm as TWA; (ACGIH 2004). MAK: Carcinogen category: 2; (DFG 2004). OSHA PEL: TWA 0.2 ppm (0.4 mg/m3) NIOSH REL: TWA 0.2 ppm (0.4 mg/m3) NIOSH IDLH: 2 ppm ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation. INHALATION RISK: A harmful concentration of this gas in the air will be reached very quickly on loss of containment. EFFECTS OF SHORT-TERM EXPOSURE: The substance is very corrosive to the eyes, the skin and the respiratory tract. Inhalation of the vapour may cause lung oedema (see Notes). Inhalation of the vapour may cause asthmatic reactions (see Notes). The liquid may cause frostbite. Exposure above the OEL may result in death. Medical observation is indicated. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: Repeated or prolonged inhalation exposure may cause asthma. This substance is possibly carcinogenic to humans. PHYSICAL PROPERTIES Boiling point: -23°C Melting point: -145°C Relative density (water = 1): 1.45 Solubility in water: reaction Relative vapour density (air = 1): 1.4 Flash point: Flammable Gas Auto-ignition temperature: (explosion) 100°C ENVIRONMENTAL DATA N O T E S Because of its toxicity and its explosive nature, diazomethane is freshly prepared in situ and used in solution of ether or dioxane. The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. Immediate administration of an appropriate spray, by a doctor or a person authorized by him/her, should be considered. The symptoms of asthma often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. The relation between odour and the occupational exposure limit cannot be indicated. The recommendations on this Card also apply to concentrated solutions of diazomethane. Card has been partly updated in April 2005. See sections Occupational Exposure Limits, EU classification, Emergency Response. ADDITIONAL INFORMATION ICSC: 1256 DIAZOMETHANE (C) IPCS, CEC, 1994

IMPORTANT LEGAL NOTICE: Neither NIOSH, the CEC or the IPCS nor any person acting on behalf of NIOSH, the CEC or the IPCS is responsible for the use which might be made of this information. This card contains the collective views of the IPCS Peer Review Committee and may not reflect in all cases all the detailed requirements included in national legislation on the subject. The user should verify compliance of the cards with the relevant legislation in the country of use. The only modifications made to produce the U.S. version is inclusion of the OSHA PELs, NIOSH RELs and NIOSH IDLH values.