International Chemical Safety Cards METHACRYLALDEHYDE ICSC: 1259 2-Methyl-2-propenal Isobutenal Methacrolein C4H6O / CH2=C(CH3)CHO Molecular mass: 70.1 ICSC #    1259 CAS #     78-85-3 RTECS # OZ2625000 UN #        2396 March 15, 1995 Peer reviewed 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. Do NOT use compressed air for filling, discharging, or handling. Use non-sparking handtools. In case of fire: keep drums, etc., cool by spraying with water. EXPOSURE PREVENT GENERATION OF MISTS!  •INHALATION Cough. Sore throat. Ventilation, local exhaust, or breathing protection. Fresh air, rest.  •SKIN MAY BE ABSORBED! Redness. Pain. Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention.  •EYES Redness. Pain. Safety spectacles, 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. Rinse mouth. Induce vomiting (ONLY IN CONSCIOUS PERSONS!). Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Collect leaking liquid in sealable containers. Absorb remaining liquid in sand or inert absorbent and remove to safe place. (Extra personal protection: complete protective clothing including self-contained breathing apparatus). Fireproof. Separated from strong oxidants, acids, bases, food and feedstuffs. Cooled. Keep in the dark. Well closed. Keep under inert gas. Store only if stabilized. Unbreakable packaging; put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs. R: S: UN Hazard Class: 3 UN Subsidiary Risks: 6.1 UN Packing Group: II SEE IMPORTANT INFORMATION ON BACK ICSC: 1259 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 METHACRYLALDEHYDE ICSC: 1259 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS LIQUID , WITH CHARACTERISTIC ODOUR. PHYSICAL DANGERS: The vapour is heavier than air and may travel along the ground; distant ignition possible. CHEMICAL DANGERS: The substance can polymerize due to warming or under the influence of light, acids and bases, with fire or explosion hazard. Reacts violently with alkalies, amines, strong acids and peroxides. OCCUPATIONAL EXPOSURE LIMITS: TLV not established. ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation of its vapour and by ingestion. INHALATION RISK: A harmful contamination of the air can be reached very quickly on evaporation of this substance at 20°C. EFFECTS OF SHORT-TERM EXPOSURE: The substance irritates the eyes, the skin and the respiratory tract. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: PHYSICAL PROPERTIES Boiling point: 68°C Melting point: -81°C Relative density (water = 1): 0.8 Solubility in water, g/100 ml at 20°C: 6 Vapour pressure, kPa at 20°C: 16 Relative vapour density (air = 1): 2.42 Flash point: -15°C Auto-ignition temperature: 295°C Explosive limits, vol% in air: 2.6-? ENVIRONMENTAL DATA N O T E S Health effects of exposure to the substance have not been investigated. An added stabilizer or inhibitor can influence the toxicological properties of this substance, consult an expert. Check for peroxides prior to distillation; eliminate if found. Transport Emergency Card: TEC (R)-30G32 NFPA Code: H3; F3; R2; ADDITIONAL INFORMATION ICSC: 1259 METHACRYLALDEHYDE (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.