Quality Glossary Definition: Failure mode effects analysis (FMEA)
Also called: potential failure modes and effects analysis; failure modes, effects and criticality analysis (FMECA)
Begun in the 1940s by the U.S. military, failure modes and effects analysis (FMEA) is a step-by-step approach for identifying all possible failures in a design, a manufacturing or assembly process, or a product or service. It is a common process analysis tool.
- "Failure modes"means the ways, or modes, in which something might fail. Failures are any errors or defects, especially ones that affect the customer, and can be potential or actual.
- "Effects analysis"refers to studying the consequences of those failures.
Failures are prioritized according to how serious their consequences are, how frequently they occur, and how easily they can be detected. The purpose of the FMEA is to take actions to eliminate or reduce failures, starting with the highest-priority ones.
Failure modes and effects analysis also documents current knowledge and actions about the risks of failures, for use in continuous improvement. FMEA is used during design to prevent failures. Later it’s used for control, before and during ongoing operation of the process. Ideally, FMEA begins during the earliest conceptual stages of design and continues throughout the life of the product or service.
- When to use FMEA
- FMEA procedure
- FMEA example
- FMEA resources
Failure Modes and Effects Analysis Example
When to Use FMEA
- When a process, product, or service is being designed or redesigned, after quality function deployment (QFD)
- When an existing process, product, or service is being applied in a new way
- Before developing control plans for a new or modified process
- When improvement goals are planned for an existing process, product, or service
- When analyzing failures of an existing process, product, or service
- Periodically throughout the life of the process, product, or service
FMEA Procedure
Note: This is a general procedure. Specific details may vary with standards of your organization or industry. Before undertaking an FMEA process, learn more about standards and specific methods in your organization and industry through other references and training.
- Assemble a cross-functional teamof people with diverse knowledge about the process, product or service, and customer needs. Functions often included are: design, manufacturing, quality, testing, reliability, maintenance, purchasing (and suppliers), sales, marketing (and customers), and customer service.
- Identify the scope of the FMEA. Is it for concept, system, design, process, or service? What are the boundaries? How detailed should we be? Use flowchartsto identify the scope and to make sure every team member understands it in detail.
- Fill in the identifying information at the top of your FMEA form. (Figure 1 shows a typical format.) The remaining steps ask for information that will go into the columns of the form.
Figure 1: FMEA Example
- Identify the functions of your scope. Ask, "What is the purpose of this system, design, process, or service? What do our customers expect it to do?" Name it with a verb followed by a noun. Usually one will break the scope into separate subsystems, items, parts, assemblies, or process steps and identify the function of each.
- For each function, identify all the ways failure could happen. These are potential failure modes. If necessary, go back and rewrite the function with more detail to be sure the failure modes show a loss of that function.
- For each failure mode, identify all the consequences on the system, related systems, process, related processes, product, service, customer, or regulations. These are potential effects of failure. Ask, "What does the customer experience because of this failure? What happens when this failure occurs?"
- Determine how serious each effect is. This is the severity rating, or S. Severity is usually rated on a scale from 1 to 10, where 1 is insignificant and 10 is catastrophic. If a failure mode has more than one effect, write on the FMEA table only the highest severity rating for that failure mode.
- For each failure mode, determine all the potential root causes. Use tools classified as cause analysis tools, as well as the best knowledge and experience of the team. List all possible causes for each failure mode on the FMEA form.
- For each cause, determine the occurrence rating, or O. This rating estimates the probability of failure occurring for that reason during the lifetime of your scope. Occurrence is usually rated on a scale from 1 to 10, where 1 is extremely unlikely and 10 is inevitable. On the FMEA table, list the occurrence rating for each cause.
- For each cause, identify current process controls. These are tests, procedures or mechanisms that you now have in place to keep failures from reaching the customer. These controls might prevent the cause from happening, reduce the likelihood that it will happen or detect failure after the cause has already happened but before the customer is affected.
- For each control, determine the detection rating, or D. This rating estimates how well the controls can detect either the cause or its failure mode after they have happened but before the customer is affected. Detection is usually rated on a scale from 1 to 10, where 1 means the control is absolutely certain to detect the problem and 10 means the control is certain not to detect the problem (or no control exists). On the FMEA table, list the detection rating for each cause.
- Optional for most industries:Ask, "Is this failure mode associated with a critical characteristic?" (Critical characteristics are measurements or indicators that reflect safety or compliance with government regulations and need special controls.) If so, a column labeled "Classification" receives a Y or N to show whether special controls are needed. Usually, critical characteristics have a severity of 9 or 10 and occurrence and detection ratings above 3.
- Calculate the risk priority number, or RPN, which equals S × O × D. Also calculate Criticality by multiplying severity by occurrence, S × O. These numbers provide guidance for ranking potential failures in the order they should be addressed.
- Identify recommended actions. These actions may be design or process changes to lower severity or occurrence. They may be additional controls to improve detection. Also note who is responsible for the actions and target completion dates.
- As actions are completed, note results and the date on the FMEA form. Also, note new S, O, or D ratings and new RPNs.
FMEA Example
A bank performed a process FMEA on their ATM system. Figure 1 shows part of it: the function "dispense cash" and a few of the failure modes for that function. The optional "Classification" column was not used. Only the headings are shown for the rightmost (action) columns.
Notice that RPN and criticality prioritize causes differently. According to the RPN, "machine jams" and "heavy computer network traffic" are the first and second highest risks.
One high value for severity or occurrence times a detection rating of 10 generates a high RPN. Criticality does not include the detection rating, so it rates highest the only cause with medium to high values for both severity and occurrence: "out of cash." The team should use their experience and judgment to determine appropriate priorities for action.
FMEA Resources
You can also search articles, case studies, and publicationsfor FMEA resources.
Books
The ASQ Pocket Guide to Failure Mode and Effect Analysis
Failure Mode And Effect Analysis: FMEA from Theory to Execution
Handbook Of Investigation And Effective CAPA Systems
The Quality Toolbox
Risk Management Using Failure Mode And Effect Analysis
Articles
Solve Your FMEA Frustrations (Lean & Six Sigma Review) The concept of FMEA is rather simple and widely known, but in practice, a huge variation in quality and competency exists. Confusion and various opinions about how to handle details exist. This article sheds some light on common confusion and disputes.
Blueprint For Success (Six Sigma Forum Magazine) One area in which FMEA has not been substantively deployed as a tool of risk management is that of corporate real estate construction and management. This article applies FMEA to capital projects in architecture and construction.
Courses
Failure Mode and Effects Analysis – Managing Risk
Failure Mode and Effects Analysis (FMEA): A Hands-On Guide to the Fundamentals
FMEA for Beginners
Videos
FMEA and Sensitivity Analysis Eugene Bukowski, Senior Engineering Manager, GE Healthcare, describes sensitivity analysis, a new approach to determining and prioritizing failure modes. Bukowski also names some of the common failure modes and discusses risk priority number.
Risk Management and FMEA Hear from Denise Robitaille, U.S. Technical Advisory Group to Technical Committee 176, on why the ISO 9001:2015 revision moved away from preventive action toward risk-based thinking, and learn how traditional preventive actions tools can satisfy the new requirements.
Adapted from The Quality Toolbox, ASQ Quality Press.
FAQs
What is FMEA? Failure Mode & Effects Analysis? ›
Overview: Failure Mode and Effects Analysis (FMEA) is a structured way to identify and address potential problems, or failures and their resulting effects on the system or process before an adverse event occurs. In comparison, root cause analysis (RCA) is a structured way to address problems after they occur.
What is FMEA failure modes and effect analysis? ›Failure Modes and Effects Analysis (FMEA) is a systematic, proactive method for evaluating a process to identify where and how it might fail and to assess the relative impact of different failures, in order to identify the parts of the process that are most in need of change.
What does failure modes mean in the FMEA? ›"Failure modes" means the ways, or modes, in which something might fail. Failures are any errors or defects, especially ones that affect the customer, and can be potential or actual. "Effects analysis" refers to studying the consequences of those failures.
What question does FMEA answer? ›Failure Mode Effects Analysis (FMEA) is a tool that helps us anticipate what might go wrong with a product or process. We can also use it to identify the possible causes and probabilities of failures.
What is an example of failure mode and effect analysis? ›In the FMEA in Figure 1, for example, a flat tire severely affects the customer driving the car (rating of 10), but has a low level of occurrence (2) and can be detected fairly easily (3). Therefore, the RPN for this failure mode is 10 x 2 x 3 = 60.
What is an example of a FMEA? ›FMEA Example
Identify Potential Failure Modes - All of the manners in which the part or process could fail. Cracked, loosened, deformed, leaking, oxidized, overlooked, etc. For example, MRI's produce intense magnetic fields. One patient was killed by a flying fire extinguisher pulled off the wall by the MRI.
- Step 1: Identify potential failures and effects. The first FMEA step is to analyze functional requirements and their effects to identify all failure modes. ...
- Step 2: Determine severity. Severity is the seriousness of failure consequences of failure. ...
- Step 3: Gauge likelihood of occurrence. ...
- Step 4: Failure detection.
For mechanical devices, there are four Failure Mechanisms: corrosion, erosion, fatigue and overload. While those Failure mechanisms exists many places in nature, they may or may not be present in the specific working environment of an asset.
What is the purpose of the FMEA? ›FMEA involves identifying and eliminating process failures for the purpose of preventing an undesirable event. When to use FMEA: FMEA is effective in evaluating both new and existing processes and systems. For new processes, it identifies potential bottlenecks or unintended consequences prior to implementation.
What is the general purpose of FMEA? ›Failure Mode and Effects Analysis, or FMEA, is a methodology aimed at allowing organizations to anticipate failure during the design stage by identifying all of the possible failures in a design or manufacturing process.
What is an example of failure mode and effects analysis in healthcare? ›
Examples may include: Patient death or major loss of physiological function, wrong surgery, wrong patient, wrong body part removed, infant abduction or improper discharge, death to visitor / hospital staff (or hospitalization of 3 or more staff), equipment damage of $250,000+ or fire.
What is the FMEA score? ›Each category has a scoring matrix with a 1-10 scale. Severity of 1 denotes low risk to the end customer, and a score of 10 denotes high risk to the customer. Occurrence of 1 denotes low probability of the risk happening, and a 10 denotes a very high probability of the risk happening.
What are the 7 steps of FMEA? ›- Step 1: Planning and Preparation.
- Step 2: Structure Analysis.
- Step 3: Function Analysis.
- Step 4: Failure Analysis.
- Step 5: Risk Analysis.
- Step 6: Optimization.
- Step 7: Results Documentation.
Failure Mode Effect Analysis (FMEA) is one the most effective and accepted problem solving (PS) tools for most of the companies in the world. Since FMEA was first introduced in 1949, practitioners have implemented FMEA in various industries for their quality improvement initiatives.
Is FMEA a risk management tool? ›What is the FMEA. The FMEA Model is a risk management tool used to identify and manage risks within projects and across entire departments and organisations. It can be a process FMEA (where the risks are process failures) or a design FMEA (where the risks are product or system-related failures).
What is the most important part of FMEA? ›Control. At the most basic level, the significance of the FMEA process is to aid in quality control. Whether it is a product, a system, or a process under analysis, the goal is to evaluate ways to prevent, detect, and mitigate failures of any kind.
What are the tools used in FMEA? ›- The 5 whys (“Sakichi Toyoda”)
- Affinity diagram (“Kawakita Jiro“)
- Cause-effect or fishbone diagram (“Ishikawa”)
- SIPOC diagram or Flow diagrams.
- FMEA.
- Improve product/process reliability and quality.
- Increase customer satisfaction.
- Early identification and elimination of potential product/process failure modes.
- Prioritize product/process deficiencies.
- Capture engineering/organization knowledge.
- Emphasizes problem prevention.
First, identify what product or process you want to assess. The FMEA analysis is comprehensive, so you want to focus on a specific process with a narrow scope. If you are already aware of an issue, that's a good place to start.
Who is responsible for FMEA? ›The Design FMEA must be owned by the person responsible for creating the design. The Process FMEA must be owned by the person responsible for the processes that will be used to produce the product.
Is FMEA a Six Sigma tool? ›
FMEA is considered by many to be the perfect Six Sigma tool.
What is the most common failure mode? ›In materials science, fatigue – the weakening of a material caused by cyclic loading resulting in progressive, brittle, localized structural damage – is the most common failure mode and the one that generally produces other types of failure.
What is the difference between failure and failure mode? ›A failure may originate from an error. When the failure occurs, the item enters a fault state. A failure mode is the way in which an item could fail to perform its required function.
What are the two main types of failure? ›Think of it this way: There are two kinds of failure. The first comes from never trying out your ideas because you are afraid, or because you are waiting for the perfect time. This kind of failure you can never learn from, and such timidity will destroy you. The second kind comes from a bold and venturesome spirit.
What is a FMEA diagram? ›An FMEA Block diagram (or Boundary diagram) is a visual depiction of the entire system or design to clearly show the boundaries of the FMEA (i.e., what is included and not included), the interfaces between the items and other information that can help to depict the scope of the analysis.
What is the difference between risk and failure mode? ›A risk, according to ISO 14971, is defined as a hazardous situation that may lead to a harm to the patient, user, or the environment. The hazardous situation may also be called a failure mode, and it is triggered by a failure cause.
What are the two types of process control in FMEA? ›There are often two types of controls identified in an FMEA: prevention-type controls and detection-type controls.
How does an FMEA help a project manager? ›FMEA is an effective tool for managing risks because it helps identify potential problems early in the development process before they have a chance to impact the project negatively. Using FMEA, project managers can address high-priority issues before they become costly mistakes.
Is FMEA qualitative or quantitative? ›Failure Mode and Effect Analysis (FMEA) is classified as the semi-quantitative method. The Risk Priority Number (RPN) in FMEA supports the quantitative analysis of risk events.
Is FMEA a lean tool? ›When combined together, FMEA for lean manufacturing yields a tactical process of analyzing the vulnerability of a manufacturing cycle while also minimizing waste and increasing flow in small production environments. The unique characteristic of FMEA is the fact that you can use it on multiple levels or stages.
What is risk priority level in FMEA? ›
Formula: The Risk Priority Number, or RPN, is a numeric assessment of risk assigned to a process, or steps in a process, as part of Failure Modes and Effects Analysis (FMEA), in which a team assigns each failure mode numeric values that quantify likelihood of occurrence, likelihood of detection, and severity of impact.
Is FMEA lean or Six Sigma? ›FMEA is the quintessential Six Sigma tool. It helps decrease defects while increasing customer satisfaction.
What are the most important criteria for FMEA to be successful? ›- A sound knowledge of the basics of FMEA.
- Proper preparations for the FMEA procedure.
- Avoid common mistakes.
- A skilled FMEA facilitator.
Satisfying the 5 Ts: InTent, Timing, Team, Tasks, and Tools
Defining the scope and the boundaries of the FMEA analysis.
- Step 1: Identify potential failures and effects. The first FMEA step is to analyze functional requirements and their effects to identify all failure modes. ...
- Step 2: Determine severity. Severity is the seriousness of failure consequences of failure. ...
- Step 3: Gauge likelihood of occurrence. ...
- Step 4: Failure detection.
Examples may include: Patient death or major loss of physiological function, wrong surgery, wrong patient, wrong body part removed, infant abduction or improper discharge, death to visitor / hospital staff (or hospitalization of 3 or more staff), equipment damage of $250,000+ or fire.
What are the 4 failure modes? ›(1) Material-interaction-induced mechanisms. (2) Stress-induced mechanisms. (3) Mechanically induced failure mechanisms. (4) Environmentally induced failure mechanisms.
What is the purpose of FMEA? ›FMEA involves identifying and eliminating process failures for the purpose of preventing an undesirable event. When to use FMEA: FMEA is effective in evaluating both new and existing processes and systems. For new processes, it identifies potential bottlenecks or unintended consequences prior to implementation.
What are the two main types of FMEA? ›Design FMEA (DFMEA) Process FMEA (PFMEA)
What causes FMEA failure? ›For Design FMEAs, the cause is the design deficiency that results in the failure mode. For Process FMEAs, the cause is the manufacturing or assembly deficiency (or source of variation) that results in the failure mode.
What are the three failure modes? ›
Examples of failure modes are: Ductile fracture. Brittle fracture. Fatigue fracture.
Is FMEA a quality tool? ›It is the technique par excellence of quality tools. They are the abbreviations of Failure mode and effects analysis (FMEA). FMEA is based on the application of a procedure for classifying potential failures based on their severity, frequency and detection capacity.
What are the three attributes of a failure in FMEA? ›All these three attributes (Severity, Priority, and Likelihood) are individually measured in scale and then multiplied to get a Risk Priority Number (RPN).
What are the three attributes of a failure that the FMEA scores? ›There are often three FMEA attributes for failure modes, including occurrence (O), detectability (D), and severity (S). Each FMEA attribute is scored using a ten-point scale.