International Chemical Safety Cards POTASSIUM HEXAFLUOROSILICATE ICSC: 1242 Potassium fluorosilicate Potassium silicofluoride Dipotassium hexafluorosilicate K2SiF6 Molecular mass: 220.3 ICSC #    1242 CAS #     16871-90-2 RTECS # VV8400000 UN #        2655 EC #         009-012-00-0 October 27, 1994 Peer reviewed 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. In case of fire in the surroundings: use appropriate extinguishing media. EXPLOSION EXPOSURE PREVENT DISPERSION OF DUST!  •INHALATION Burning sensation. Cough. Sore throat. See Ingestion. Avoid inhalation of fine dust and mist. Local exhaust or breathing protection. Fresh air, rest. Refer for medical attention.  •SKIN Redness. Pain. Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower.  •EYES Redness. Pain. Safety goggles or eye protection in combination with breathing protection if powder. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Abdominal cramps. Burning sensation. Nausea. Vomiting. Do not eat, drink, or smoke during work. Wash hands before eating. Rinse mouth. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Do NOT wash away into sewer. Sweep spilled substance into sealable containers; if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place. Personal protection: P3 filter respirator for toxic particles. Separated from acids, food and feedstuffs . Do not transport with food and feedstuffs. Marine pollutant. Note: A T symbol R: 23/24/25 S: 1/2-26-45 UN Hazard Class: 6.1 UN Packing Group: III SEE IMPORTANT INFORMATION ON BACK ICSC: 1242 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 POTASSIUM HEXAFLUOROSILICATE ICSC: 1242 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: WHITE CRYSTALS OR FINE POWDER. PHYSICAL DANGERS: CHEMICAL DANGERS: The substance decomposes on heating producing toxic and corrosive fumes including fluorine. Reacts with concentrated acids to produce corrosive hydrogen fluoride (see ICSC0283). OCCUPATIONAL EXPOSURE LIMITS: TLV: as F) 2.5 mg/m³ as TWA; A4 (not classifiable as a human carcinogen); BEI issued; (ACGIH 2004). MAK: (Inhalable fraction) 2.5 mg/m³; Peak limitation category: II(2); (DFG 2004). ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation of its aerosol and by ingestion. INHALATION RISK: Evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly when dispersed. 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 calcium metabolism , resulting in cardiac disorders and impaired functions . Medical observation is indicated. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: The substance may have effects on the bone , resulting in fluorosis. PHYSICAL PROPERTIES Melting point (decomposes): see Notes Relative density (water = 1): 2.3 Solubility in water: none ENVIRONMENTAL DATA N O T E S Temperature of decomposition unknown in literature. Card has been partly updated in April 2005. See sections Occupational Exposure Limits, Emergency Response. Transport Emergency Card: TEC (R)-61GT5-III ADDITIONAL INFORMATION ICSC: 1242 POTASSIUM HEXAFLUOROSILICATE (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.