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Risk breakdown structure

Risk breakdown structure is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Risk breakdown structure rather than just read about it. In short: A Risk Breakdown Structure (RBS) within risk management is a hierarchically organised depiction of the identified project risks arranged by category. An Introduction to the Risk Breakdown Structure When planning a project to meet targets for cost, schedule, or quality, it is useful to identify likely risks to the success of the project.

Risk breakdown structure — main illustration
Risk breakdown structure — illustration

Key takeaways

  • Risk breakdown structure belongs to engineering; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Risk breakdown structure to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Risk breakdown structure from memory before moving on to harder problems.

Reference excerpt

A Risk Breakdown Structure (RBS) within risk management is a hierarchically organised depiction of the identified project risks arranged by category.

An Introduction to the Risk Breakdown Structure When planning a project to meet targets for cost, schedule, or quality, it is useful to identify likely risks to the success of the project. A risk is any possible situation that is not planned for, but that, if it occurs, is likely to divert the project from its planned result. For example, an established project team plans for the work to be done by its staff, but there is the risk that an employee may unexpectedly leave the team. In Project Management, the Risk Management Process has the objectives of identifying, assessing, and managing risks, both positive and negative. All too often, project managers focus only on negative risk, however, good things can happen in a project, "things" that were foreseen, but not expressly planned. The objective of Risk Management is to predict risks, assess their likelihood and impact, and to actively plan what should be done ahead of time to best deal with situations when they occur. The risk management process usually occurs in five distinct steps: plan risk management, risk identification, qualitative and quantitative risk analysis, risk response planning, and risk monitoring and control. The central point of risk identification and assessment in risk management is understanding the risk. However, this is also where project managers and risk subject-matter experts (SMEs) get the least help from recognized references, best practices, or work standards. The Project Management Institute (PMI) has developed a Practice Standard for Risk Management, produced by a team of subject-matter experts. As part of this standard, the Risk Breakdown Structure (RBS) is identified as a tool intended to assist project managers, risk managers, and stakeholders in identifying and assessing risk.

What is a "Risk Breakdown Structure?" The RBS will prove extremely valuable to better grasp when a project needs to receive special scrutiny, in other words, when risk might happen. The RBS can also help the project manager and the risk manager to better understand recurring risks and concentrations of risk that could lead to issues that affect the status of the project. Following the concept of the Work Breakdown Structure (WBS), the Risk Breakdown Structure provides a means for the project manager and risk manager to structure the risks being addressed or tracked. Just as PMI defines the Work Breakdown Structure as a "deliverable-oriented grouping of project elements that organizes and defines the total work scope of the project...", the RBS could be considered as a "hierarchically organized depiction of the identified project risks arranged by risk category." In project management language, risks include anything unplanned and unforeseen that can have a negative impact on the project's costs, timing or quality. (This does not conform to the ISO 31000 view of Risk.) A good project manager should be able to manage the risks effectively and get the project on track. Many project managers and risk managers currently use "home-grown" methods for listing, identifying, assessing, and tracking risks in their projects. These methods include: spreadsheets, listing, generic risk taxonomy, based somewhat loosely on various standards and guidelines.

An approach that simply places the risks in a list, a simple table, or even in a database does not provide the strength of using a structured, organized method similar to a Work Breakdown Structure. To fully understand the risks and better identify and assess the risk, a "deep-dive" into each risk, recording as many levels of identification as necessary, may be required. The project value of placing risks in a structure such as this lies in the ability of the project manager and risk manager to then quickly and easily identify and assess the risk, identify the potential risk triggers, and develop a more robust risk response plan . If all risks are placed in a hierarchical structure as they are identified, and the structure is organized by source, the total risk exposure to the project can be more easily understood, and planning for the risk more easily accomplished.

Templates for creating a Risk Breakdown Structure

The concept of the RBS is new. The PMBoK (2004), barely references its use; however, the PMI Standards team has incorporated the RBS in the Practice Standard for Risk Management (draft for release in 2009). The PMBoK provides an example graphic of the RBS in Chapter 11, Figure 11.4. This reference has as major topics: Technical, External, Organizational, and Project Management. Another source provides the following major topics: Technical, Management, Organizational, External, and Project Management. Dr. David Hillson, in the proceedings of the Project Management Institute Annual Seminars and Symposium, on Oct. 3–10, 2002, provided several different RBS Structure examples, with topics similar to those already shown. Dr. Hillson broke out two different examples, an RBS for Software Development, which had the following major topics: Product Engineering, Development Environment, Program Constraints; and an RBS for Construction Design, which has these major topics: Environment, Industry, Client, Project. Each RBS is broken into "levels", with each level providing a more in-depth "view" of the identified risk. As an example, in creating a RBS for software development, Level 1 of the RBS might be Technical, followed by Level 2, Requirements, followed by Level 3, Functional Requirements, Informational Requirements, Non-functional Requirements, etc. If desired, Level 3 can be further refined with Level 4, Stability, Completeness, Functionality, Interfaces, Testability, etc., Level 5, etc. Once the project team has created its RBS, then individual risks can be identified. Several different techniques for defining the individual risks are available, including brain-storming, surveys, workshops, etc. Each identified risk needs to be categorized, and placed in the RBS under a specific topic (or topics) if the risk spans two or more topics, such as a risk in gathering requirements might span Technical, organizational and project management.

NOTE: the RBS will be different between projects, even projects within the same project area, e.g., construction, information technology, environmental remediation, etc.

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with Risk breakdown structure

Start with the simplest possible case. Write down what Risk breakdown structure claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Risk breakdown structure before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Risk breakdown structure ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Risk breakdown structure

In research
Risk breakdown structure appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Risk breakdown structure in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Risk breakdown structure is common in secondary-school and first-year university syllabi. It links to neighbouring topics Management science, Project management, Project management techniques, so understanding it makes those chapters shorter.
In everyday life
Look for Risk breakdown structure outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Risk breakdown structure in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Risk breakdown structure means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Risk breakdown structure out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Risk breakdown structure in simple terms?

A Risk Breakdown Structure (RBS) within risk management is a hierarchically organised depiction of the identified project risks arranged by category. An Introduction to the Risk Breakdown Structure When planning a project to meet targets for cost, schedule, or quality, it is useful to identify like…

Why does Risk breakdown structure matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Risk breakdown structure?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Risk breakdown structure.

Tags

  • Management science
  • Project management
  • Project management techniques
  • Risk analysis
  • Risk management
  • Systems engineering

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