---
title: "Degradation Management Theory - Overview"
slug: "degradation-management-theory-overview"
updated: 2026-10-27T23:11:38Z
published: 2026-10-27T23:11:38Z
canonical: "ims-handbook.cenosco.com/degradation-management-theory-overview"
---

> ## 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.

# Degradation Management Theory - Overview

**This online manual explains the background theory of Degradation Management:**

- What Degradation Management is.
- What Degradation Mechanisms (DMs) are.
- What Barriers are.
- What a Corrosion Management Framework (CMF) is.
- How Corrosion Loops (CLs) and Systems, including Integrity Operating Windows (IOWs), play a role in Degradation Management.
- What Risk Based Inspection (RBI) is.

Note: In [PEI Degradation Management - Implementation](/v414/docs/work-process-degradation-management-implementation-steps) we show you step by step how to implement Degradation Management in IMS.  

Every plant is subjected to several potential [Degradation Mechanisms (DMs)](/v414/docs/degradation-classification-theory), which need to be carefully controlled to avoid unsafe situations and/or high costs. Degradation Management is about the management of these DMs for Pressure Equipment, Piping and Pipelines.

In IMS Degradation Mechanisms (DMs) and their associated [Barriers](/v414/docs/barrier-types) are captured within defined IMS objects - Corrosion Loops. Subsequently, Risk-Based methodologies such as [S-RBI](/v414/docs/risk-based-inspection-rbi-theory) or [RBI581](/docs/degradation-management-using-api-rbi-581) are used to optimize inspections and monitoring strategies.

## The Three Phases of Degradation Management

Degradation Management has three main phases: Threat Identification, Barrier Design, and Barrier Maintenance.

![](https://cdn.document360.io/e492a0e0-a4ba-4aca-8fc6-76b95f91fdf3/Images/Documentation/Three%20Phases%20(2).png?sv=2026-02-06&spr=https&st=2026-10-28T19%3A24%3A55Z&se=2026-10-28T20%3A24%3A55Z&sr=c&sp=r&sig=3KGzwbrbN0STFILUbcPKXERbvGWcw10%2F4uXqCLXlUtc%3D)The Degradation Management Phases.

In the image above, the three main phases are shown together with their important sub-phases (for the implementation of these phases – go to the referenced Steps):

- **Threat Identification**
  - Collect and capture asset information. ([Step 1](/v414/docs/step-1-define-the-asset))
  - [Defining CL Boundaries, Process and Potential DMs](/v414/docs/defining-cl-boundaries-process-and-potential-dms) (including effective materials, susceptible areas, damage rates and the parameters that affect them. ([Step 2](/v414/docs/step-2-identify-threats-and-barriers-define-the-cl-1))
  - [Identify the Degradation Mechanisms](/v414/docs/defining-the-degradation-mechanisms). ([Step 2](/v414/docs/step-2-identify-threats-and-barriers-define-the-cl-1))
- **Barrier** identification and **Design**
  - [Identify the Barriers](/v414/docs/defining-the-barriers-and-linking-to-iows). ([Step 2](/v414/docs/step-2-identify-threats-and-barriers-define-the-cl-1))
  - Asses the Barrier effectiveness and requirement for additional Barriers. ([Step 2](/v414/docs/step-2-identify-threats-and-barriers-define-the-cl-1))
  - Design a Barrier verification & maintenance plan: Determine inspection, monitoring and maintenance activities to confirm Barrier statuses. ***This is where S-RBI Analyses comes in*** ([Step 3](/v414/docs/step-3-start-rbi-analysis-and-assign-dms-to-the-component-1) to [Step 12](/v414/docs/step-12-assign-s-rbi-results-to-inspectioncorrosion-schedules-andor-update-monitoring-plan)).
- **Barrier** health **Verification and** **Maintenance**
  - Execute the verification plan - inspect, analyze and document. ([Step 13](/v414/docs/step-13-barrier-verification-execute-analyze-document))
  - Review the Barrier Statuses. ([Step 13](/v414/docs/step-13-barrier-verification-execute-analyze-document))
  - Maintain the Barriers by restoring compromised or failed Barriers. ([Step 14](/v414/docs/step-14-maintain-the-barriers-1))

## The Bowtie Model

Threats and Barriers can also be described in terms of the Bowtie Model.

![](https://cdn.document360.io/e492a0e0-a4ba-4aca-8fc6-76b95f91fdf3/Images/Documentation/the-bowtie-model-image-das1o8yn.png?sv=2026-02-06&spr=https&st=2026-10-28T19%3A24%3A55Z&se=2026-10-28T20%3A24%3A55Z&sr=c&sp=r&sig=3KGzwbrbN0STFILUbcPKXERbvGWcw10%2F4uXqCLXlUtc%3D)The Bowtie mode.The Bowtie model definitions:

- **Threat**: What may cause the **Top Event** (i.e. the **Threat** is the [Degradation Mechanism](/v414/docs/degradation-classification-theory)).
- [**Barrier**](/v414/docs/barrier-types): (1) What directly reduces the likelihood of the **Threat** leading to the **Top Event**, and (2) What directly reduces the likelihood of the **Scenario** (worst-case **Consequence**).
- **Top Event**: The first event to release the **Hazard**.
- **Hazard**: A situation or substance that influences the **Consequence** of the **Top Event**.
- **Scenario**: Description of worst-case **Consequence** of the **Top Event** (the **Hazard** release).
- **Consequence**: Actual effect of the **Top Event** (Hazard release).

## Degradation Management Workflow

Let's have a look at the [Degradation Management Workflow](/v414/docs/degradation-management-work-process-in-ims).