Explosion, with consequent fire, in chemicals production plantThe accident occurred in the organo-metallic compound production unit, on a transport container for aluminum alkyls, which exploded during a cleansing process at the washing station. The incident was caused by a pressure build-up inside the container caused by flammable gases, mainly hydrogen, formed by the chemical reaction of aqueous caustic soda solution with the aluminum alkyl residues. This cleansing of the transport containers is a standard procedure after return from customers and before a new filling. However, in this particular case, even after several attempts it was impossible to completely remove the deposits on the inner wall of the container. Tests aiming at the detection of reactive alkyl residues showed negative results. Thus, the deposits were exposed to an aqueous solution of caustic soda (NaOH). Since no production of heat or gases had been detected over a period of several hours, to increase the effectiveness of the cleaning procedure the container was sealed (against the instruction) and kept revolving around its longitudinal axis on a roller system. After a short time of this process, the container burst, torn apart along the longitudinal axis, while part of is bottom was blown away and damaged a heptane pipeline. The released heptane ignited, and the whole building caught fire. The container had been sealed infringing operating instructions. The substances involved were aluminum, aluminum alkyls, heptane (HCCH), sodium hydroxide (NaOH), hydrogen.