International Chemical Safety Cards PARALDEHYDE ICSC: 1042 p-Acetaldehyde Paracetaldehyde 2,4,6-Trimethyl-1,3,5-trioxane C6H12O3 Molecular mass: 132.2 ICSC #    1042 CAS #     123-63-7 RTECS # YK0525000 UN #        1264 EC #         605-004-00-1 October 08, 2002 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. Water spray, alcohol-resistant foam, dry powder, carbon dioxide. EXPLOSION Above 24°C explosive vapour/air mixtures may be formed. Above 24°C use a closed system, ventilation, and explosion-proof electrical equipment. In case of fire: keep drums, etc., cool by spraying with water. EXPOSURE  •INHALATION Burning sensation. Cough. Shortness of breath. Further see Ingestion. Ventilation, local exhaust, or breathing protection. Fresh air, rest. Refer for medical attention.  •SKIN Redness. Pain. Protective gloves. Remove contaminated clothes. Rinse and then wash skin with water and soap.  •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 Burning sensation in the throat and chest. Nausea. Vomiting. Diarrhoea. Drowsiness. Unconsciousness. Do not eat, drink, or smoke during work. Do NOT induce vomiting. Give plenty of water to drink. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Remove all ignition sources. Collect leaking and spilled liquid in sealable non plastic containers as far as possible. Absorb remaining liquid in sand or inert absorbent and remove to safe place. (Extra personal protection: filter respirator for organic gases and vapours.) Fireproof. Separated from food and feedstuffs , bases and oxidants . Do not transport with food and feedstuffs. F symbol R: 11 S: 2-9-16-29-33 UN Hazard Class: 3 UN Packing Group: III SEE IMPORTANT INFORMATION ON BACK ICSC: 1042 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 PARALDEHYDE ICSC: 1042 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 decomposes on standing, under the influence of air and light . The substance decomposes on heating producing toxic fumes . Reacts with bases and oxidants . Attacks plastic. 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: 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: The substance is irritating to the eyes , the skin and the respiratory tract . The substance may cause effects on the central nervous system . EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: The substance may have effects on the nervous system , resulting in addiction. The substance may have effects on the kidneys and liver , resulting in impaired functions . PHYSICAL PROPERTIES Boiling point: 124.5°C Melting point: 12.6°C Density: 0.99 g/cm3 Solubility in water, g/100 ml at 13°C: 12 Vapour pressure, kPa at 20°C: 1 Relative vapour density (air = 1): 4.5 Flash point: 24°C c.c. Auto-ignition temperature: 235°C Explosive limits, vol% in air: 1.3-17.0 Octanol/water partition coefficient as log Pow: 0.67 ENVIRONMENTAL DATA N O T E S Transport Emergency Card: TEC (R)-30S1264 NFPA Code: H2; F3; R1; ADDITIONAL INFORMATION ICSC: 1042 PARALDEHYDE (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.