Since 1987 – Safety Consultancy

Consequences Analysis

The top-events that can lead to no-negligible consequences in a refinery are thousands. This is because quite every pipeline, tank, equipment, etc. is filled with a dangerous substance and a simple failure of any gasket or seal on this stuff will lead to a top-event with significant consequences. The knowledge of the consultant becomes critical when choosing among the thousands, the hundreds really relevant. Eidos consultants have decades of experience in Refinery safety and can advise with knowledge the customer.

Consequence analysis is carried on to evaluate the extent of the possible consequences associated to a top-event and it is usually an integral part of a safety review (or QRA or PHA).

The consequences related to a plant top-event are usually assessed in the QRA or PHA of a plant. Please refer to Plant Safety for further details.

At the Refinery level, the consequences are modelled in relation to Site-wide top-events as highlighted in the top-events identification, HazOp, QRA/PHA pages, some types of top-events are better suited to be studied at a Refinery level and Eidos has developed specific methods for these top-events:

  • Production of missiles made of ductile material due to explosions and their effects on people, buildings and equipments when the source and the target are different plants. Missiles production is more relevant in case outdoor plants, like the ones of the refineries
  • Effects on buildings from explosion blasts when the explosion source is located in a different plant or the buildings are not related to the plants (management offices, IT offices and so on). This issue is particularly important in refineries’ centralized control rooms that overview a set of plants
  • Domino effects arising from heat radiations, explosion blasts and missile productions when the source and the target are different plants or the targets are not related to any plant). Eidos has developed two different sets of model for screening or detailed evaluation. Domino effects are really relevant in a Refinery because usually the plants are quite compact and close to each other to optimize the related costs. This compactness increases the likelihood of domino effects and the need for prevention and protection efforts.
  • Consequences coming from seismic waves (screening method developed with Politecnico di Torino University). This aspect is really important in the refineries mainly for:
    • pipe-racks due to their extension and the pillars oscillating in a asynchronous manner
    • process columns due to the constrains coming from inlet and outlet pipes
    • large storage tanks due to the sloshing effect
  • Production of debris made of brittle material due to explosions and their effects on people, buildings and equipments when the source and the target are different plants
  • Consequences of spills of dangerous substances on ground waters, rivers and seas. In this case the target is not a plant

Eidos is licensed to DNV Phast Multicomponent with the new radiation shielding extension.

Eidos employs skilled personnel on GIS (ArcInfo) and CAD (Autodesk) to produce consequence plots. Due to the size usually associated to a Refinery the use of a GIS system really makes sense. Eidos is skilled in using ArcInfo or Google solutions (Earth and Sketch Pro). In last years Google Earth is becoming more and more popular. This, and the fact that is free, leads the Authorities to ask for Consequences representation to be supplied in kmz format (the native format of Google Earth application). Eidos extended its knowledge on GIS/CAD to include the capability of preparing kmz consequences representations fully geo-referenced and in 3D. Please refer to Plant safety for some samples.