Alloy provides tools to support the adoption of a risk based approach to asset management and maintenance. Risk assessment is generally associated with defects and depending on the level of risk, defects may require reactive maintenance (including making safe, temporary or permanent repair) or, where a temporary repair has been completed or the defect presents a lower level of risk, will be considered for planned maintenance. Highway maintenance is a good example of how risk assessment is used to manage assets, where surface damage can require immediate repair or scheduled for future maintenance.

A common method of calculating and defining risk uses two parameters of risk:

  • Risk likelihood
  • Risk consequences

These parameters are assigned a range of values. A combination of the two sets of parameter values allows you to define the severity of the risk which can then be use to trigger a response, for example, immediate repair or scheduled repair.

The following table illustrates a basic risk assessment set of calculations from which the severity of the risk is determined by the score.

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The number of divisions of the risk likelihood and the risk consequence can vary but the general principal is common to most methods of calculating risk.

Risk Assessment module

Alloy provides a Risk Assessment module that allows you to incorporate risk based management when creating defects. The module consists of a risk interface, risk designs and a risk calculation mesh that you can use to configure your risk calculation method.

Risk interface

The risk interface includes a set of attributes, which when the interface is added to any defect design are included in the design. This allows you to create defects that are used as part of a risk based management approach.

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The interface includes four key risk attributes:

  • Risk consequences
  • Risk likelihood
  • Risk severity
  • Risk score

Consequences, likelihood and severity are link attributes that connect through to corresponding lookup designs.

Risk designs

There are three risk lookup designs that are used to create / edit items that allow you to the define the consequences and likelihood ranges as well as categories of severity, used to calculate the risk.

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You can add / edit / delete items to create parameter values to reflect the risk model that you want to use.

Risk calculation workflow

The final part of the module is the risk calculation workflow. This is triggered when a defect that incorporates the risk interface, is created or edited.

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When the workflow is triggered the values of the Consequences and Likelihood are passed to a mesh that calculates the risk Score, this is used to determine the Severity of risk. The mesh updates the score and severity within the defect that was created or edited.

You can create additional workflows that are triggered by the status of the defect, once risk severity has been defined, to initiate maintenance procedures.