Daesim Risk Assessor

Daesim Risk Assessor is an integrated risk assessment tool for hazardous installations and operations that provides impact analysis, detailed event consequence calculations, construction of incidents from events and vulnerability models, construction of scenarios that locate incidents on a site plan and then the calculation of consequence and risk contours. The range of events available consists of liquid and gas releases, pool formation, fires, explosions and gas dispersion. A thermo-physical database of properties provides key data to the risk assessments.


Risk Assessor also has a client-server architecture that facilitates group work from a central database of documents and local messaging between users.

User interaction

Risk Assessor provides facilities to interactivity build incidents from events using a graphical interface where the events and linkages can be defined, and then saved to a project database. All event models such as pool fires, warehouse fires, explosions and gas releases are fully configurable. Scenarios can be built to generate iso-risk contours on plot plans or to give impact zones for specific effect levels such as thermal radiation or explosion overpressure.

Event and incident models

Event models are built from well-known industry sources such as the UK Health and Safety Executive, The Netherlands industrial research organisation TNO and other well respected references or research works. Events and incidents (sequence of events) can be investigated for uncertainty in input parameters such as emissive power of the flame or carbon to hydrogen ratio of the fuel. Event models can also be combined with vulnerability models, typically in the form of probability unit models (Probits) to generate impacts on vulnerable resources such as people, plant or environment. Shell’s heavy gas model, HGsystem is built into the software.


Other Features

Complex scenarios can be built from combining all relevant site incidents, coupled with generic frequency data or site specific data to generate a range of risk representations, which include physical impact maps or iso-risk contours. Frequency data can also be supplied through linked fault trees or events trees.



The system provides a flexible analysis environment and an ability to understand the risk analysis steps through generated logs and results files. Sensitivity of outcomes to uncertainties in input parameters provides improved risk insights and important decision making information.

Risk Assessor has been used for many industrial applications as well as for Major Hazard Facility (MHF) assessments for over 10 years.