igure $1$ below illustrates the Fault Tree Analysis used to investigate the root causes of the wrong raw material being added to a bioreactor. The following potential root causes and their corresponding probabilities of occurrence were identified:Potential root causeProbability of Potential root cause occurrenceProbability of occurrence$0\mathrm{.}100\mathrm{.}25$Management system failure $0\mathrm{.}01$ Equipment failure $0\mathrm{.}05$Human error #$30\mathrm{.}30$Labelling procedure $0\mathrm{.}20$ inadequateHuman error #$2$Arrival$-$check procedure inadequateHuman error #$10\mathrm{.}15$