What is the FMEA (Failure Mode & Effect Analysis)? How
to use FMEA or When to use FMEA? The purpose of FMEA (Failure Mode & Effect
Analysis) is to take action to eliminate or reduce failure.
Failures are always priorities according to how serious
their consequences are, how frequently they occur, and how easily the failure
or defect can be detected.
Ideally, the FMEA (Failure Mode & Effect Analysis)
begins during the earliest conceptual stage of the design and continues
throughout the life of products or services. FMEA (Failure Mode & Effect
Analysis) is always used during design to prevent failure. Later it's used for
control, before and during the ongoing operation of the process.
What is the History of FMEA (Failure Mode & Effect Analysis)?
It was first formalized in the aerospace industry during the Apollo program in the 1960s. After that FMEA (Failure Mode & Effect Analysis) has been adopted in the automobile sector in the 1970s. Now the FMEA (Failure Mode & Effect Analysis) function has been adopted in almost every industry.
When to use FMEA (Failure Mode & Effect Analysis)?
- When a Process, Product, or Service is being designed or re-design.
- When an existing Process, Product, or Service is being designed in a new format or new skillset.
- Before developing a control plan for a new or modified process.
- When Improvement goals are planned for an existing Process, Product, or service.
- When analyzing the failure of an existing process, Product, or Service.
How to Use FMEA (Failure Mode & Effect Analysis)?
- Assemble a cross-functional team with diverse knowledge about customer requirements, Products, Processes, or services.
- Identify the scope of FMEA (Failure Mode & Effect Analysis). Identify whether is it for the concept, system, product design, or customer service? What are the boundaries? How detailed should we be? Suggestion: Use: Flow chart to identify the scope for FMEA and make sure that every team member understands it in detail.
- For each function, identify all the ways failure could happen. If necessary, go back and rewrite the function with more in-depth details to be sure the failure modes show a loss of that function.
- For each failure mode, identify all consequences on the system, related system, Process, related process, product, services, or regulations. There are potential effects of failure. Ask: What happens when this type of failure occurs?
- Determine how serious each effect is. This is the severity rating, or S. Severity is always scaled from 1 to 10, where 1 is significant and 10 is catastrophic. If the 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 classified tools to identify the root causes.
- For each cause, determine the occurrence rating or O. This rating estimates the probability of failure occurrence. Occurrence is usually rated on a 1 to 10 rating scale. Where 1 is extremely unlikely & 10 is inevitable. List the occurrence rating for each cause on the FMEA table.
- For each cause, identify the current process controls. These are the test, Procedures, and mechanisms that you now have in place to keep failure from reaching the customer.
- For each control, determine the detection rating, or D. This rating estimate how well the controls can detect either the cause or its failure mode after they happened but before the customer is affected. Detection is usually rated on a scale of 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 existence in the process. List the occurrence rating for each cause on the FMEA table.
- Calculate the risk priority number (RPN). Which equals S x O x D. Also calculate criticality by multiplying severity or occurrence, which equals S x O. This number provides guidance for ranking potential failures in the order they should be addressed.
