Critical amount of silicon trichlorohydride hazard source

4. Physical and chemical properties Molecular weight: 135.43 Melting point (101.325 kPa): -134℃； Boiling point (101.325 kPa): 31.8℃ ； Liquid density (0°C): 1350 kg/m3 ； Relative density (gas, air=1): 4.7 ； Vapor pressure (-16.4°C): 13.3kPa ； (14.5℃): 53.3kPa ； Ignition point: -27.8℃ ； Autoignition point: 104.4℃ ； Flash point: -14℃ ； Explosion limit: 6.9～70% ； Toxicity level: 3 ； Flammability rating: 4 ； Explosivity level: 2 Trichlorosilane is a colorless and transparent liquid that is highly volatile, flammable, and has an irritating, foul odor at normal temperature and pressure. It burns very easily in air, and there is a risk of ignition even at temperatures below -18°C. When exposed to an open flame, it burns vigorously, producing red flames and white smoke; SiO2, HCl, and Cl2 are formed as by-products: SiHCl3 + O2 → SiO2 + HCl + Cl2 ； Vapors of trichlorosilane can form explosive mixtures with air over a wide range of concentrations, leading to violent explosions when heated. Its thermal stability is better than that of dichlorosilane; at 900°C, it decomposes to produce toxic hydrogen chloride fumes, as well as Cl2 and Si. 　　It emits smoke in the presence of moisture and reacts violently with water: 2SiHCl3+3H2O—→ (HSiO)2O+6HCl ； 　　Hydrogen is released upon decomposition in an alkaline solution: SiHCl3 + 3NaOH + H2O → Si(OH)4 + 3NaCl + H2 ； 　　It undergoes an explosive reaction when in contact with oxidizing substances. It reacts with hydrocarbons such as acetylene and hydrocarbons to produce organochlorosilanes: SiHCl3 + CH≡CH → CH2CHSiCl3, SiHCl3 + CH2=CH2 → CH3CH2SiCl3. In the presence of lithium aluminum hydride or lithium borohydride, SiHCl3 can be reduced to silanes. The liquid SiHCl3 in the container can catch fire when the container is subjected to a severe impact. It is soluble in benzene, ether, etc. Anhydrous trichlorosilane does not corrode iron and stainless steel, but it corrodes most metals in the presence of moisture. 　　5. Toxicity 　 Mouse inhalation LC50: 1.5–2 mg/L 　 Maximum allowable concentration: 1 mg/m3

The critical amount for the hazard source of trichlorosilane is 10 tons

The critical amount for the trichlorosilane hazard source is 10 tons, with a hazard level of grade 2