HazId studies carried on an existing plant, are used to assess, in a semi-quantitative way (risk matrix), the major risks related to them.
Sometimes plant managers need to evaluate, in a faster way, the impact on safety related to some modification to their plant before committing the engineering.
Plant managers also have to deal with Management of Change System that very often involves a “no-increase of risk” policy. In this case Eidos can provide to the managers a fast and flexible way of evaluating different proposed modifications in terms of:
- increase of risk by frequency or severity of consequences
- spread of risk to surrounding areas by magnitude of consequences and exposure levels
Of course Eidos “engineering first” approach will support managers in seeking solution that will cope with policies.
According to what said before, Eidos uses sometimes a hybrid approach where the identification of the top-events is done using the “HazId” approach but the following risk evaluation is based on a full quantitative approach (fault trees – event trees – consequences calculation): no unpleasant surprises in later stages!
Eidos usually employs HazId also during:
- the feasibility phase of a new project to help the customer assessing the safety (and the costs related). Please refer to Engineering Assistance.
- the screening phase of a site safety assessment to identify the units to be investigated with HazOp analysis (this is an alternative approach to DOW index or derivative) Please refer to Industrial Safety or Refinery Safety.
- the screening phase of a plant domino effect risk analysis to identify major accidents as the source of the concatenation of events when a complete site safety review is not available and not requested by customer. Please refer to Industrial Safety or Refinery Safety.