At a chemical plant manufacturing phytosanitary products, an explosion occurred on a multi-purpose unit; this blast was followed by the formation of a black, foul-smelling cloud hovering over the city, causing an electricity outage that disturbed rail traffic for several hours. Residents in the vicinity of the installation were ordered to remain indoors, though the majority of window panes on nearby dwellings were shattered by the explosion. The human toll amounted to: 2 severely burned employees, 7 other employees and 2 fire-fighters with minor burns, and 91 members of the general public suffered from breathing difficulties or cuts due to broken glass. The facility was destroyed within a 200-m radius around the reactor. The explosion occurred once the reactor, loaded with 1,600 kg of reagents and with an operational stirrer, had reached a temperature of 90°C. The investigation revealed that a mistake in type of reagent during loading caused this accident: potassium hydroxide had been used instead of potassium carbonate. The ensuing exothermic reaction quickly ran away, preventing any human response and negating any benefit from the valve protection system in place. The plant would be rebuilt on a site far from any dwellings with an improved product identification procedure, yet in failing to introduce a bar code-based automatic locking system (as prescribed by oversight authorities).

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