International Chemical Safety Cards NITROUS OXIDE ICSC: 0067 Dinitrogen monoxide Hyponitrous acid anhydride Laughing gas Dinitrogen oxide N2O Molecular mass: 44.0 (cylinder) ICSC #    0067 CAS #     10024-97-2 RTECS # QX1350000 UN #        1070 (compressed) May 08, 2003 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Not combustible but enhances combustion of other substances. Gives off irritating or toxic fumes (or gases) in a fire. NO open flames, NO sparks, and NO smoking. In case of fire in the surroundings: use appropriate extinguishing media. EXPLOSION Risk of fire and explosion: see Chemical Dangers .>> Closed system, ventilation, explosion-proof electrical equipment and lighting. In case of fire: keep cylinder cool by spraying with water. Combat fire from a sheltered position. EXPOSURE AVOID EXPOSURE OF (PREGNANT) WOMEN!  •INHALATION Euphoria. Drowsiness. Unconsciousness. Ventilation. Local exhaust or breathing protection. Fresh air, rest. Refer for medical attention.  •SKIN ON CONTACT WITH LIQUID: FROSTBITE. Cold-insulating gloves. ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer for medical attention.  •EYES ON CONTACT WITH LIQUID: FROSTBITE. Safety goggles 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. If in liquid state: do NOT absorb in saw-dust or other combustible absorbents. NEVER direct water jet on liquid. Personal protection: self-contained breathing apparatus. Fireproof if in building. Separated from incompatible materials . See Chemical Dangers. Cool. R: S: UN Hazard Class: 2.2 UN Subsidiary Risks: 5.1 SEE IMPORTANT INFORMATION ON BACK ICSC: 0067 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 NITROUS OXIDE ICSC: 0067 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS COMPRESSED LIQUEFIED GAS , WITH CHARACTERISTIC ODOUR. PHYSICAL DANGERS: The gas is heavier than air and may accumulate in low ceiling spaces causing deficiency of oxygen. CHEMICAL DANGERS: Reacts violently with sulphurous anhydride, amorphous boron, phosphine, ethers, aluminium, hydrazine, phenyl-lithium and tungsten carbide causing fire and explosion hazard. The gas is a strong oxidant above 300°C and may form explosive mixtures with ammonia, carbon monoxide, hydrogen sulfide, oil, grease and fuels. OCCUPATIONAL EXPOSURE LIMITS: TLV: 50 ppm as TWA; A4 (not classifiable as a human carcinogen); (ACGIH 2004). MAK: 100 ppm, 180 mg/m³; Peak limitation category: II(2); Pregnancy risk group: D; (DFG 2004). OSHA PEL: none NIOSH REL: TWA 25 ppm (46 mg/m3) (TWA over the time exposed) *Note: REL for exposure to waste anesthetic gas. NIOSH IDLH: No data 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 liquid may cause frostbite. The substance may cause effects on the central nervous system , resulting in lowering of consciousness . EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: The substance may have effects on the bone marrow and peripheral nervous system . May cause reproductive toxicity in humans. PHYSICAL PROPERTIES Boiling point: -88.5°C Melting point: -90.8°C Relative density (water = 1): 1.23 at -89°C Solubility in water, g/100 ml at 15°C: 0.15 Vapour pressure, kPa at 20°C: 5150 Relative vapour density (air = 1): 1.53 Octanol/water partition coefficient as log Pow: 0.35 ENVIRONMENTAL DATA N O T E S Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. Other UN number: 2201 Nitrous oxide, refrigerated liquid. Card has been partly updated in April 2005. See section Occupational Exposure Limits. Transport Emergency Card: TEC (R)-20S1070 ADDITIONAL INFORMATION ICSC: 0067 NITROUS OXIDE (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.