Poison by ingestion and inhalation, and a poisonous irritant to skin, eyes, and mucous membranes. Toxicity is based on HCl which is formed upon hydrolysis of a chlorosilane. Self-ignites in air. With a little ammonia, it forms a self-igniting product. They react with water or steam to produce heat and toxic and corrosive fumes of HCl. When heated to decomposition they emit highly toxic fumes of Cl⁻.