HAZOP Risk Matrix Configuration Guide
The HAZOP Risk Matrix Configuration process ensures hazardous scenarios are evaluated consistently across your organisation. By defining severity classifications, likelihood values and risk rankings, organisations can standardise risk assessment while supporting HAZOP studies and ongoing operational risk management.
Within the Mangan Software Solutions SLM platform, the risk matrix automatically classifies scenarios captured during HAZOP studies, helping teams visualise risk, prioritise mitigation activities and maintain consistent corporate standards across multiple facilities.
Why HAZOP Risk Matrix Configuration Matters
A well-designed HAZOP risk matrix helps organisations assess hazardous scenarios consistently across every Process Hazard Analysis (PHA). By standardising how severity and likelihood are measured, teams can compare risks objectively and prioritise mitigation activities more effectively.
Within the Mangan Software Solutions SLM platform, the configured risk matrix automatically classifies scenarios entered during HAZOP studies. This reduces manual calculations while improving reporting consistency across facilities and operating sites.
To understand how risk assessment fits into the wider study process, read the HAZOP Facilitation guide.
How to Configure a HAZOP Risk Matrix
HAZOP Risk Matrix Configuration begins within the SLM Global Module, where administrators define the framework that HAZOP teams will use to classify hazardous scenarios.
The configuration process typically includes:
- Creating severity classes
- Defining severity levels
- Adding likelihood values
- Assigning risk ranking values
- Applying risk matrix colours
- Synchronising the completed matrix across the organisation
Once configured, these values become available during HAZOP execution so facilitators and study teams can apply an agreed corporate risk methodology consistently.
Configuring Severity Classes
Severity classes represent the different categories of consequence an organisation wants to assess during a HAZOP study. These classes allow teams to evaluate more than personnel safety alone.
Common severity classes include:
- Personnel safety
- Environmental impact
- Commercial impact
- Reputational impact
- Organisation-specific consequence categories
Each class should reflect the organisation’s approved risk criteria and the types of consequences that need to be considered during HAZOP facilitation.
Administrative controls, study settings and supporting configuration activities are covered further in the HAZOP Administration guide.
Severity Classes and Severity Levels
Severity classes define what type of consequence is being assessed, while severity levels define how serious that consequence is.
For example, an organisation may create a personnel safety class with five levels ranging from minor injury to multiple fatalities. Environmental and commercial classes can use the same number of levels while applying definitions relevant to those consequence types.
For a five-by-five risk matrix, each severity class will normally require five clearly defined severity levels. Each level can include a short description, a detailed definition, a display order and the target mitigated event likelihood associated with that consequence.
Clear definitions help HAZOP teams classify scenarios consistently and reduce differences in interpretation between studies.
Configuring Likelihood Values
Likelihood values define how probable an initiating cause or hazardous event is. These values form the second dimension of the risk matrix and are selected during HAZOP scenario assessment.
Each likelihood value can include:
- A display order
- A short description
- A detailed description
- A minimum probability
- A maximum probability
- An initiating-cause likelihood value
Likelihood bands should be based on the organisation’s risk assessment standard and should be sufficiently clear for HAZOP teams to distinguish between each category.
Once saved, the configured values become selectable within HAZOP studies and are used automatically when calculating scenario risk rankings.
Defining Risk Ranking Values and Colours
Once severity and likelihood values have been configured, SLM generates the possible combinations required to build the risk matrix.
Administrators can then assign:
- A risk ranking value for each combination
- A background colour for the matrix cell
- A foreground or font colour
- The organisation’s preferred risk classification terminology
Consistent colour coding allows users to identify higher-risk scenarios quickly across studies, reports and Dynamic Risk Matrix views.
The selected ranking should reflect the organisation’s approved risk tolerance and mitigation requirements rather than being treated as a purely visual setting.
Enterprise and Site Risk Matrix Configuration
Organisations must decide whether one standard risk matrix will apply across the enterprise or whether individual facilities require their own configurations.
Where the risk methodology is standardised, administrators can create the matrix once at enterprise level and synchronise it to individual sites. This reduces duplicated configuration work and helps maintain common definitions across the organisation.
Where operating sites use different consequence criteria, regulatory thresholds or corporate standards, separate matrices can be configured at site level.
SLM therefore supports both centralised governance and site-specific risk assessment requirements without forcing every facility to use an identical model.
Using the Dynamic Risk Matrix in HAZOP Studies
As HAZOP scenarios are assessed, users select the initiating-cause likelihood and the relevant severity level for each consequence category.
SLM then automatically applies the configured matrix rules to calculate the risk ranking, target mitigated event likelihood and associated colour classification.
The Dynamic Risk Matrix allows users to:
- Visualise the distribution of HAZOP scenarios
- Identify concentrations of higher-risk scenarios
- Review scenarios within a selected matrix cell
- Navigate back to the associated HAZOP study or node
- Compare risk exposure across units or sites
The wider benefits of managing studies within a structured digital environment are explained on the MSS HAZOP Software page.
Managing Risk Reduction and HAZOP Recommendations
A risk matrix does more than classify the initial level of risk. It also helps study teams determine whether further safeguards, design changes or operational controls are required.
Where a scenario requires additional mitigation, the HAZOP team can raise recommendations and assign actions to the appropriate responsible parties.
Structured action management helps organisations:
- Record the reason for each recommendation
- Assign responsibility and due dates
- Monitor action status
- Maintain an auditable record of risk reduction decisions
- Confirm that required mitigation has been completed
For more information about managing recommendations after a study, see the HAZOP Action Tracking Software guide.
HAZOP Risk Matrix Configuration Best Practices
Effective HAZOP Risk Matrix Configuration depends on clear definitions, consistent governance and agreement between process safety stakeholders. Before beginning HAZOP Risk Matrix Configuration, organisations should confirm that the selected severity, likelihood and risk ranking criteria reflect their approved corporate risk standard.
- Confirm the corporate risk standard before beginning configuration.
- Use unambiguous descriptions for every severity and likelihood level.
- Keep probability ranges consistent and avoid overlapping definitions.
- Apply the same risk ranking colours across studies and reports.
- Decide whether the matrix should be controlled at enterprise or site level.
- Test the completed configuration before using it in a live HAZOP study.
- Review the matrix periodically as organisational risk criteria change.
For an independent industry definition of how likelihood and consequence are combined within a matrix, see the AIChE Center for Chemical Process Safety risk matrix guidance.
Regular review of HAZOP Risk Matrix Configuration helps study teams make consistent decisions, supports reliable reporting and strengthens the overall governance of HAZOP risk assessment.
