Chain of accidents (domino effect) in chemical process industries

A past accident analysis (PAA) covering major accidents that have occurred in the chemical process industry from the dawn of the previous century upto the present day, reveals that such accidents have rarely began and ended with a single episode of explosion and/or fire. More often than not the first episode has set off another major accident; the letter, in turn, provoking a third accident, and so on. For example a vapour cloud explosion caused by a leak in the polyethylene plant of a Phillips unit near Houston, Texes, (the USA) on 3 October, 1989, led to the damage, one after another, of as many as nine other installations, each of which exploded violently. The well-known disasters at Feyzin (1966), Laurel (1969), and Mexico City (1984), are among innumerable instances that have occurred throughout the history of chemical process industry when one event of fire or explosion has caused a second event