International Chemical Safety Cards 2,3-BUTANEDIONE ICSC: 1168 2,3-BUTANEDIONE Diacetyl Dimethylglyoxal Dimethyl diketone 2,3-Diketobutane CH3COCOCH3/C4H6O2 Molecular mass: 86.1 CAS # 431-03-8 0 RTECS # EK2625000 ICSC # 1168 UN # 2346 TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Highly flammable. NO open flames, NO sparks, and NO smoking. Powder, alcohol-resistant foam, water spray, carbon dioxide. EXPLOSION Vapour/air mixtures are explosive. Closed system, ventilation, explosion-proof electrical equipment and lighting. In case of fire: keep drums, etc., cool by spraying with water.   EXPOSURE PREVENT GENERATION OF MISTS! INHALATION Ventilation, local exhaust, or breathing protection. Fresh air, rest. SKIN Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower. EYES Safety spectacles. 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. Wash hands before eating. Rinse mouth. Give plenty of water to drink. Rest. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Collect leaking liquid in covered containers. Absorb remaining liquid in sand or inert absorbent and remove to safe place (extra personal protection: A/P2 filter respirator for organic vapour and harmful dust). Fireproof. UN Hazard Class: 3 UN Packing Group: II SEE IMPORTANT INFORMATION ON BACK ICSC: 1168 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities © IPCS CEC 1993

International Chemical Safety Cards 2,3-BUTANEDIONE ICSC: 1168 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: GREEN TO YELLOW MOBILE LIQUID. PHYSICAL DANGERS: The vapour is heavier than air and may travel along the ground; distant ignition possible. CHEMICAL DANGERS: Heating may cause violent combustion or explosion. OCCUPATIONAL EXPOSURE LIMITS (OELs): TLV not established. ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation and through the skin. INHALATION RISK: No indication can be given about the rate in which a harmful concentration in the air is reached on evaporation of this substance at 20°C. EFFECTS OF SHORT-TERM EXPOSURE: EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: Repeated or prolonged contact may cause skin sensitization. PHYSICAL PROPERTIES Boiling point: 88°C Melting point: -2.4°C Relative density (water = 1): 1 Solubility in water: miscible Relative vapour density (air = 1): 3 Flash point: 6°C Octanol/water partition coefficient as log Pow: -1.34

ENVIRONMENTAL DATA
N O T E S
Explosive limits are unknown in literature, although the substance is highly flammable and has a flash point <21°c. Transport Emergency Card: TEC (R)-30G30 NFPA Code: H1; F3; R0

ADDITIONAL INFORMATION
ICSC: 1168 2,3-BUTANEDIONE © IPCS, CEC, 1993

IMPORTANT LEGAL NOTICE: Neither the CEC or the IPCS nor any person acting on behalf of 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.