LOPA

The LOPA can be viewed by clicking on the required Hazard ->SIL Determination -> LOPA.

A summary of the configured Initiating Events, IPLs and Conditional Modifiers can be viewed.

The LOPA tab is only available if the Determination methods for the Hazard are set to include LOPA.

Initiating Events

Initiating Events are added to the LOPA. See the Initiating Events guide.

Independent Protection Layers & Conditional Modifiers

Independent Protection Layers (IPLs) & Conditional Modifiers are added to the LOPA. See the IPLs and Conditional Modifiers guide.

Consequences

LOPA Consequence View
LOPA Consequence View – Showing Safety Results

The total Intermediate Event Frequency and resulting Target PFD will potentially be different for different Consequence Categories (Safety, Environment, etc.) because of not all Conditional Modifiers apply to all Categories. You can switch the LOPA view to each selected Consequence Category on the Hazard to review the application of Conditional Modifiers and the results.

Consequence are set on the Hazard on the Hazards Form and are configured in the Risk Profile Configuration.

Summary Overview for Low Demand SIFs

View a summary of each Initiating Event with its corresponding frequency, and the configured IPLs and Conditional Modifiers with their respective factors.

The calculated Intermediate Event Frequency is presented for each Initiating Event. The Intermediate Event Frequency presents the frequency of the initiating event occurring taking into account all mitigation factors (IPLs and Conditional Modifiers).

The Intermediate Event Frequency and Total Intermediate Event Frequency are calculated with a frequency of ‘per year’.

Also shown in the Summary are the Target Risk Frequency (set via Hazards Form), the Total Intermediate Event Frequency (sum of the individual Mitigated Event Frequencies), the calculated Target SIL and the Target PFD of the SIF being analysed.

Summary Overview for Continuous / High Demand SIFs

LOPA for Continuous / High Demand Hazard
LOPA for Continuous / High Demand Hazard

As the SIF is continuous the only Initiating Event is the failure of the SIF. All configured IPLs and Conditional Modifiers are presented with their respective factors. The Total IPL Factors column shows the combined Factors for the IPLs and the Total Modifier Factors shows the combined Factors for the Conditional Modifiers.

Also shown in the Summary are the Target Risk Frequency (set via Hazards Form), the Total IPL Factors, the Total Modifier Factors, the calculated Target SIL and the Target PFH of the SIF being analysed.