International Chemical Safety Cards CESIUM HYDROXIDE ICSC: 1592 Cesium hydrate Caesium hydroxide CsOH Molecular mass: 149.91 ICSC #    1592 CAS #     21351-79-1 RTECS # FK9800000 UN #        2682 April 06, 2006 Validated po, ned from Geneva TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Not combustible. Gives off irritating or toxic fumes (or gases) in a fire. Contact with moisture or water may generate sufficient heat to ignite combustible substances. In case of fire in the surroundings: use appropriate extinguishing media. EXPLOSION Risk of explosion on contact with oxidants . In case of fire: cool drums, etc., by spraying with water but avoid contact of the substance with water. EXPOSURE  •INHALATION Cough. Shortness of breath. Sore throat. Local exhaust or breathing protection. Fresh air, rest. Half-upright position. Refer for medical attention.  •SKIN Skin burns. Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention.  •EYES Severe deep burns. Face shield First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Abdominal pain. Burning sensation. Shock or collapse. Do not eat, drink, or smoke during work. Rinse mouth. Do NOT induce vomiting. Give one or two glasses of water to drink. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Personal protection: P2 filter respirator for harmful particles. Chemical protection suit. Sweep spilled substance into plastic sealable containers. Wash away remainder with plenty of water. Dry. Well closed. Separated from combustibles, acids, strong oxidants, metals, food and feedstuffs . Do not transport with food and feedstuffs. UN Hazard Class: 8 UN Packing Group: II SEE IMPORTANT INFORMATION ON BACK ICSC: 1592 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 CESIUM HYDROXIDE ICSC: 1592 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS TO YELLOW HYGROSCOPIC CRYSTALS . PHYSICAL DANGERS: CHEMICAL DANGERS: Reacts violently with water , producing heat. The substance is a strong base, it reacts violently with acid and is corrosive to metals. Attacks many metals forming flammable/explosive gas (hydrogen - see ICSC 0001). OCCUPATIONAL EXPOSURE LIMITS: TLV: 2 mg/m³ as TWA (ACGIH 2004). MAK not established. ROUTES OF EXPOSURE: The substance can be absorbed into the body by ingestion. INHALATION RISK: A harmful concentration of airborne particles can be reached quickly when dispersed. EFFECTS OF SHORT-TERM EXPOSURE: The substance is corrosive to the eyes , the skin and the respiratory tract. Corrosive on ingestion. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: PHYSICAL PROPERTIES Melting point: 272°C Density: 3.68 g/cm³ Solubility in water, g/100 ml at 15°C: 395 (very good) ENVIRONMENTAL DATA N O T E S Caesium hydroxide in solution: UN 2681; UN Hazard class:8; UN Packgroup: II,III; Transport Emergency Card: TEC (R)-80GC5-II+III. Transport Emergency Card: TEC (R)-80GC6-II+III ADDITIONAL INFORMATION ICSC: 1592 CESIUM HYDROXIDE (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.