Fertilizer industries are among the chemical process industries where hazardous chemicals are handled and accidents involving heat/mass/momentum transfer can result in explosions, fires, and toxic releases. Based on experience gained from past incidents in the fertilizer industries risk assessment tools and techniques are often employed in order to identify hazards and to forecast potential disasters. These efforts have almost always focused on single events or "stand alone" accidents. The interaction of an accident with other hazardous units with the potential to cause secondary, tertiary, or higher order accidents is seldom studied. Yet, chain of accidents have been occurring in the past and the probability of a repetition in the future constantly increases because of the proximity of industrial plants and the increasing population pressure in most countries. Consequently we have developed models and computer-automated tools to study chain of accidents or "domino effects." In this paper we discuss the concept of domino effect in the context of our methodologies, and present an illustrative case study of a major fertilizer industry situated near the city of Chennai(Madras, India).