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Bird and Loftus have extended this theory to reflect the influence of management in the cause and effect of all accidents that result in a wastage of the company’s assets. The modified sequence of events becomes: a) lack of control by management, permitting b) basic causes (personal and job factors), that lead to c) immediate causes (substandard practices/conditions/errors), which are the proximate causes of d) the accident, which results in e) The loss (minor, serious or catastrophic). This modified sequence can be applied to all accidents, and is fundamental to loss control management.Accidents are defined as unplanned occurrences which result in injuries, fatalities, loss of production or damage to property and assets. Preventing accidents is extremely difficult in the absence of an understanding of the causes of accidents. Many attempts have been made to develop a prediction theory of accident causation, but so far none has been universally accepted. Researchers from different fields of science and engineering have been trying to develop a theory of accident causation which will help to identify, isolate and ultimately remove the factors that contribute to or cause accidents. In this article, a brief outline of various accident causation theories is presented

According to W.H. Heinrich (1931), who developed the so-called domino theory, 88% of all accidents are caused by unsafe acts of people, 10% by unsafe actions and 2% by “acts of God”. He proposed a “five-factor accident sequence” in which each factor would actuate the next step in the manner of toppling dominoes lined up in a row


The theory of multi causation is that the contributing causes (Behavioural, Environmental) combine together in a random fashion to result in an accident. During accident investigations, there is a need to identify as many of these causes as possible. In reality, the accident model is an amalgam of both the domino and multi causality theories.

According to the Pure Chance Theory, every one of any given set of workers has an equal chance of being involved in an accident. It further implies that there is no single discernible pattern of events that leads to an accident. In this theory, all accidents are treated as corresponding to Heinrich’s acts of God, and it is held that there exist no interventions to prevent them

Those who accept the energy transfer theory put forward the claim that a worker incurs injury or equipment suffers damage through a change of energy, and that for every change of energy there is a source, a path and a receiver. This theory is useful for determining injury causation and evaluating energy hazards and control methodology. Strategies can be developed which are preventive, limiting or ameliorating with respect to the energy transfer.

Human factors models of accident causation refer to distracting influences upon the worker by either internal or external factors. Such distracting influences are of temporary rather than permanent nature. Therefore, if care is taken to eliminate such distracting factor there is a possibility of preventing the causation of accidents. Basically, such models state that whenever human beings are overloaded due to a mismatch between the capacity of the individual and the external demand made upon him, the individual becomes more susceptible to accident.

Russell Ferrell, Professor of Human Factors at the University of Arizona is the proponent of the theory. According to this theory accident causation is attributed to a chain of events ultimately caused by human error. Human error is in turn caused by one of the three situations: overload, inappropriate response and inappropriate activities (Reason, 1990).

Peterson’s Model or Peterson’s theory is basically an extension of the Human Factors accident causation model. He introduced additional elements such as ergonomic traps, the decision to error, and the system failures. He talks of the Superman Syndrome – it won’t happen to me.

His addition of “System Failure” is an important step in identifying the potential for causal relationship between management decisions or management behaviours regarding safety. Management is responsible for setting policies, placing responsibility, training employees, following up on training, and enforcing standards with corrective actions.

Accident causation is very complex and must be understood adequately in order to improve accident prevention. Since safety lacks a theoretical base, it cannot be regarded as being a science yet. This fact should not discourage us, as most of the scientific disciplines— mathematics, statistics and so on—passed through a similarly tentative phase at one time or the other. At present, theories of accident causation are conceptual in nature and, as such, are of limited use in preventing and controlling accidents. With such a diversity of theories, it will not be difficult to understand that there does not exist one single theory that is considered right or correct and is universally accepted. These theories are nonetheless necessary, but not sufficient, for developing a frame of reference for understanding accident occurrences. Most of theories of accident causation are explicit about the importance of organisational factors in ensuring safety behaviour in the organisations. Few of the theories although not so explicit about the organisational factors, while elaborating on specific measures organisation could adopt to prevent accidents and injuries implied the importance of organisational factors. These organisational factors range from core values of the organisation, organisational structure best suited for ensuring safety, the organisational safety policy, personnel selection and placement, safety training’, management and supervisory style, priorities given to safety and productivity,· roles and responsibilities of employees to the management of stress for accurate information processing and decision making.