A blast erupted at a chemical plant during a synthesis operation involving sodium triacetoxyborohydride inside a 5,300-litre reactor. Around 5:30 pm, the technician observed that the acetic acid intake pipe was plugged. After opening the manhole with a wooden pole, the shop foreman dropped the stalactite of solidified acetic acid in the reactor: the resulting blast severely burned the foreman’s face.

The blast was caused by inflammation of the hydrogen produced from the dropped quantity of acetic acid, as the maximum amount of acetic acid introduced into the reactor was estimated by the operator at 3 kg, which led to the formation of approx. 100 grams of hydrogen in this 5,300-liter reactor. The accident had no impact either on the environment or on other shop installations.