Barium nitrate fighters, such as the Hawker Hurricane and Supermarine Spitfire, during the Battle of Britain. It is also used in the manufacturing process of barium oxide, the vacuum tube industry and for green fire in pyrotechnics. Like all soluble barium compounds, barium nitrate is toxic by ingestion or inhalation. Solutions of sulfate salts such as Epsom salts or sodium sulfate may be given as first aid for barium poisoning, as they precipitate the barium as the insoluble (and non-toxic) barium sulfate. Inhalation may also cause irritation to the respiratory tract. While skin or eye contact is less harmful than ingestion or
Barium chloride soluble in water. On an industrial scale, it is prepared via a two step process from barite (barium sulfate): This first step requires high temperatures. In place of HCl, chlorine can be used. Barium chloride can in principle be prepared from barium hydroxide or barium carbonate. These basic salts react with hydrochloric acid to give hydrated barium chloride. Although inexpensive, barium chloride finds limited applications in the laboratory and industry. In industry, barium chloride is mainly used in the purification of brine solution in caustic chlorine plants and also in the manufacture of heat treatment salts, case hardening of steel.