International Chemical Safety Cards DIBORANE ICSC: 0432 Boroethane Boron hydride Diboron hexahydride B2H6 / BH3BH3 Molecular mass: 27.7 (cylinder) (liquefied, cooled) ICSC #    0432 CAS #     19287-45-7 RTECS # HQ9275000 UN #        1911 December 03, 1990 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Extremely flammable. NO open flames, NO sparks, and NO smoking. NO contact with halogens or active metals. NO contact with hot surfaces. Shut off supply; if not possible and no risk to surroundings, let the fire burn itself out; in other cases extinguish with protein based foam. NO hydrous agents. EXPLOSION Gas/air mixtures are explosive. Heating may cause pressure rise with risk of bursting and explosion. Closed system, ventilation, explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding) if in liquid state. Use non-sparking handtools. In case of fire: cool cylinder by spraying with water but avoid contact of the substance with water. Combat fire from a sheltered position. EXPOSURE STRICT HYGIENE! IN ALL CASES CONSULT A DOCTOR!  •INHALATION Cough. Dizziness. Laboured breathing. Nausea. Sore throat. Weakness. Ventilation, local exhaust, or breathing protection. Fresh air, rest. Half-upright position. Artificial respiration if indicated. Refer for medical attention.  •SKIN Serious frostbite. Cold-insulating gloves. Rinse skin with plenty of water or shower. Refer for medical attention.  •EYES Severe deep burns. Safety goggles 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 SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Evacuate danger area! Consult an expert! Ventilation. Stop flow of gas. Spilled liquid has very low temperature and evaporates quickly. (Extra personal protection: complete protective clothing including self-contained breathing apparatus). Fireproof. Store outside or in a separate building. Separated from strong oxidants, aluminium , halogens , lithium, food and feedstuffs . Cool. Ventilation along the floor and ceiling. Special insulated cylinder. Do not transport with food and feedstuffs. R: S: UN Hazard Class: 2.3 UN Subsidiary Risks: 2.1 SEE IMPORTANT INFORMATION ON BACK ICSC: 0432 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 DIBORANE ICSC: 0432 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS COMPRESSED GAS , WITH CHARACTERISTIC ODOUR. PHYSICAL DANGERS: The gas mixes well with air, explosive mixtures are easily formed. Will ignite spontaneously in moist air at room temperature. CHEMICAL DANGERS: The substance will polymerize to form liquid pentaborane. The substance decomposes at red heat to boron and hydrogen, and at lower temperatures to hydrogen (see ICSC # 0001) and boron hydrides. Reacts spontaneously with chlorine and forms hydrides with aluminum and lithium which may ignite spontaneously in air. Reacts with many oxidized surfaces as a strong reducing agent. OCCUPATIONAL EXPOSURE LIMITS: TLV: 0.1 ppm; 0.11 mg/m3 (as TWA) (ACGIH 1990-1991). OSHA PEL: TWA 0.1 ppm (0.1 mg/m3) NIOSH REL: TWA 0.1 ppm (0.1 mg/m3) NIOSH IDLH: 15 ppm ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation. INHALATION RISK: A harmful concentration of this gas in the air will be reached very quickly on loss of containment. EFFECTS OF SHORT-TERM EXPOSURE: The substance is corrosive to the eyes, the skin and the respiratory tract. Inhalation of this substance may cause lung oedema (see Notes). Exposure may result in death. The effects may be delayed. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: Lungs may be affected by repeated or prolonged exposure. PHYSICAL PROPERTIES Boiling point: -92°C Melting point: -165°C Solubility in water: hydrolyzes to hydrogen and boric acid Relative vapour density (air = 1): 0.96 Flash point: flammable gas Auto-ignition temperature: (see Notes) 40-50°C Explosive limits, vol% in air: 0.8-88 ENVIRONMENTAL DATA N O T E S The presence of contaminants may lower the auto-ignition temperature so that ignition may occur at or below room temperature. Reacts violently with fire extinguishing agents such as halogenated agents. The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. No odour warning if toxic concentrations are present. Turn leaking cylinder with the leak up to prevent escape of gas in liquid state. Transport Emergency Card: TEC (R)-765 NFPA Code: H 3; F 4; R 3 ADDITIONAL INFORMATION ICSC: 0432 DIBORANE (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.