---
title: "Step 4 Determine most Credible Failure Scenario"
slug: "step-4-determine-the-most-credible-failure-scenario-1"
status: "update"
updated: 2026-10-27T23:12:55Z
published: 2026-10-27T23:12:55Z
canonical: "ims-handbook.cenosco.com/step-4-determine-the-most-credible-failure-scenario-1"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://ims-handbook.cenosco.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Step 4 Determine most Credible Failure Scenario

## ![](https://cdn.document360.io/e492a0e0-a4ba-4aca-8fc6-76b95f91fdf3/Images/Documentation/SRBI%20(2).jpg?sv=2026-02-06&spr=https&st=2026-10-28T12%3A56%3A35Z&se=2026-10-28T13%3A56%3A35Z&sr=c&sp=r&sig=7OMWa7OLltCVOmZoa2oUoky4o%2FULrergRSWOG2vdmOE%3D)

## Aim

When all the Barriers on the Component fail, the DM will cause a failure, i.e., a leak or a rupture. We need to establish what the most likely event is if this happens. This is called the credible failure scenario. The Susceptibility to Failure (StF) ([Step 7](/v414/docs/step-7-determine-susceptibility-to-failure-stf-1)) and Consequence of Failure (CoF) ([Step 8](/v414/docs/step-8-rate-consequence-of-failure-cof)) should be based on this Failure Scenario.

See [Methodology Step 4](/v414/docs/methodology-step-4) and [Software Step 4](/v414/docs/software-step-4).