Poor training or procedures

An operator was told to add a reactant over a certain period of time. He started to add it too slowly. Finding that he was getting behind, he added the rest too quickly, and a runaway occurred. Fortunately, in this case, the relief device controlled the situation, and the reactor did not rupture, though product was wasted. It may be necessary to specify the rate of addition as well as the time of addition. 

Operators were told to add a reactant at 45°C over a period of 1-11/ hours. They believed this to be impossible, as the heater was not powerful enough, so they decided to add it at a low er temperature and heat the material in the reactor. They did not tell anyone. This went on for a long period of time and, unknown to the supervisor, became the accepted practice. Again they were on the edge of a precipice, and ultimately a runaway reaction occurred with emission of toxic fumes. 

Unfortunately, if people are given instructions that are impossible or that they think are impossible to caiTy out, they do not like to tell their supervisors, and so they often just do the best they can. However, in this case if proper records had been kept and the supervisor examined them, he would have noticed that the addition temperature was wrong. 

Runaways have also occurred when operators added the wrong material to a reactor, often because different materials had similar names, were stored in. similar drums, or were poorly labeled (see Chapter 4). 

A batch distillation column, used for distilling nitrotoluene, had not been cleaned for 30 years. A buildup of sludge caused some problems, or 

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