Fire in a process reactor of a chemical plant.

A deflagration occurred at a chemical plant during a synthesis operation involving sodium tri-acetoxy-borohydride inside a 5,300-litre reactor.
During the progress of the synthesis reaction, the technician observed that the acetic acid (CH3COOH) intake pipe was blocked. After opening the manhole with a wooden pole, the shop foreman dropped the stalactite of solidified acetic acid in the reactor: the resulting blast injured the foreman.
The event was caused by ignition of the hydrogen produced from the dropped quantity of acetic acid. The maximum amount of acetic acid introduced into the reactor was estimated by the operator at 3 kg, and it 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.

The INITIATING cause of the blast was a manual, unplanned operation of the chemical reactor, in an attempt to troubleshooting the chemical process.
This operation brought a person direction in contact with the substances in the reactor. It was not an individual: a foreman was present. Since the problem looks as a recurrent case (the crew knew what to do), the ROOT CAUSE must be attributed to management failure to guarantee safe operations of he plant.

reactor dedicated to acetic acid, sodium tri-acetoxy-borohydride

DESCRIPTION OF THE PROCESS
Sodium triacetoxyborohydride, also known as sodium triacetoxyhydroborate, commonly abbreviated STAB, is a chemical compound with the formula Na(CH3COO)3BH. Like other borohydrides, it is used as a reducing agent in organic synthesis (Wikipedia).

Blast severely burned the foreman’s face.
The accident had no impact either on the environment or on other shop installations.