Practical Application of Fault Tree Analysis (FTA) in Problem Solving
Engineers, developers and designers are tasked with the know-how on anticipating failure well in advance of a product getting it to the consumer. Potential failure needs to be identified very early in the product development cycle in order to successfully mitigate the risk of the failure occurring. This prevention activity is with the aim of protecting the consumer from an unacceptable experience.
Among the tools for identifying potential failures and their causes / mechanisms is the Fault Tree Analysis (FTA). FTA is a deductive analysis that depicts a visual path of failure. As product and process technology becomes more complex, the visual FTA approach has proven to be invaluable as a stand-alone risk technique or a supplement to Failure Mode and Effects Analysis (FMEA).
What is Fault Tree Analysis (FTA)?
Fault Tree Analysis is a top-down, deductive analysis visually expressing a failure path or failure chain. FTA follows the concept of creating a series of statements based on True / False, and when these statements are linked in a chain, they form a logic diagram of failure. In FTA, events are arranged in sequences of series relationships (the “ors”) or parallel relationships (the “ands”).
Results for each event are presented in a tree-like diagram using logic symbols to show dependencies among events. These events are related to mechanical components, software and / or electronics that are used in the design of the product.
Top-level, undesired events are the primary topic being studied in FTA with severity classification of the Top-level event determined in a Systems-level Hazard Analysis. Fault Tree Analysis enhances valuable troubleshooting information when used in problem solving. They usually make use of failure probabilities at each level, from components and software to the undesirable Top-level event.
Reason for Performing Fault Tree Analysis (FTA)
FTA depicts a risk-based path to a root cause or base-level event. These risks drive actions intended to mitigate them prior to the launch of the program. When investigating a failure, the chain of events depicted by FTA enables the problem solver to see the events leading to a root cause(s).
When to Use the FTA
The Fault Tree Analysis is applied when:
- Previously conducted Hazard Analysis indicated a safety concern.
- A new design with new content is initiated.
- There exists a current design with modifications, which may include changes due to past failure.
- A current design is being used in a new environment or change in duty cycle (no physical change made to design).
- A safety or regulatory concern is being investigated.
- A picture of the failure proves to be more important than a written inductive analysis.
About the Author
Adebayo is a thought leader in continuous process improvement and manufacturing excellence. He is a Certified Six Sigma Master Black Belt (CSSMBB) Professional and Management Systems Lead Auditor (ISO 9001, 45001, ISO 22000/FSSC 22000 etc.) with strong experience leading various continuous improvement initiative in top manufacturing organizations.
You can reach him here.
