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Failure Mode and Effects Analysis (FMEA)

Definition of Failure Mode and Effects Analysis (FMEA):

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Do you want to be proactive in recognising and evaluating potential product or process failure modes? Do you want to reduce or eliminate the probability of a failure or defect ever getting to your customer? If you are answering yes to these questions then failure mode and effects analysis (FMEA) could be perfect for you, let’s explore further.

Overview: What is failure mode and effects analysis?

Typically described as a systematic group of activities fundamentally intended to:

  • recognize and evaluate potential failures of a product or process;
  • assess the effect of the failure and;
  • document what actions can be taken to reduce or eliminate the failure occurring

Failure mode and effects analysis has seen successful adoption across a wide range of industries and businesses forming an integral part of continuous improvement and utlizing methodologies such as root cause analysis.

We should evaluate the use of an FMEA whenever we have a process, product or service that is being designed or redesigned or, for example, has a significant change of use.

Fundamental to developing an FMEA is understanding and assigning Severity (S), Occurrence (O) and Detection (D) and the resultant Risk Priority Number (RPN = S*O*D). We will explain these terms in subsequent sections. If you are keen to know more about FMEA and industry standards then look at SAE J1739.

2 Benefits and 1 Drawback of Failure Mode and Effects Analysis

Reducing or eliminating the probability of a failure ever reaching the customer is a fundamental element of a Six Sigma approach, let’s explore some benefits and drawbacks of using FMEA.

1. Reduce rework timing and cost with failure mode and effects analysis.

We can achieve the greatest value by starting the FMEA before a product or process failure mode has been incorporated into the product or process.

2. Document risk reduction with failure mode and effects analysis.

Having a formal process and record of your risk and defect reduction actions is hugely helpful as you design and develop your product or service. It’s also great for sharing knowledge across teams and designing out failure.

3. It takes time and resource to implement failure mode and effects analysis.

Delivery of a high quality FMEA takes time, resource and commitment all of which need to be recognized and accounted for in project and work task planning.

Why is failure mode and effects analysis important to understand?

By using FMEA we have a logical and systematic group of activities that helps us design and deliver robust products and processes.

You can define all your potential failure modes and the effects of these failures.

There can be many potential failure modes and these should be described in physical or technical terms. The effects of a failure can be described as experienced by the downstream customer and a Severity (S) of the failure effect rated and assigned.

You can analyze all the potential causes for failure.

There may be more than one cause per failure mode especially when considering operating conditions and customer usage. For all potential causes an assessment of how often this cause of failure will happen is assigned, known as Occurrence (O).

You can assess your current failure management techniques and decide if further mitigation is required.

All the current controls in place to detect causes of failure modes are documented and assessed for their effectiveness, known as Detection (D). Calculation of a Risk Priority Number (RPN = S*O*D) can be used to agree recommended actions to further mitigate risk.

An Industry Example of Failure Mode and Effects Analysis

High performance internal combustion engines are complex machines with multiple potential failure modes and some catastrophic effects of failure. When developing an all new engine the design team of a global car manufacturer embraced failure mode and effects analysis early in the project.

Assembling a well trained team of engineers and diligently working through the many failure modes, effects and causes they reviewed what preventive actions were possible and appropriate. Further they agreed what special actions needed to be taken to reduce the risk of failure or defect ever getting to a customer.

The engine launched to a global market 2 years ago and has one of the best reliability records of any high technology and performance engine to date, in many ways thanks to the correct and timely utilization of failure mode and effects analysis.

3 Best Practices When Thinking About Failure Mode and Effect Analysis

As with many process driven activities there are some fundamentals to get right and help us with delivery, here are 3 to consider:

1. Timeliness

FMEA’s are a “before-the-event” action, not an “after-the-fact” exercise. Up front time spent properly completing an FMEA, when product or process changes can be most easily and inexpensively implemented, will minimise late change crises.

2. Training

Make sure the team is up to speed on how to conduct an FMEA. Assembling the right cross functional team with good knowledge and experience of conducting FMEA’s is key.

3. Tenacity

Keep with it and make the FMEA a living document. It’s a significant investment in time and resource to generate an FMEA, don’t lock it away in a file, keep it active through the product or process lifecycle.

Frequently Asked Questions (FAQ) about Failure Mode and Effect Analysis

1. What’s an acceptable RPN?

There is no simple answer and it will depend upon your products, processes and quality history. Review those high Severity failures coupled with medium to high Occurrence and design these failure modes out.

2. Can I use software to generate my FMEA?

Yes, there are many software packages that help with the construction of the FMEA and process steps but there is no such thing as auto generation.

3. Is FMEA required for ISO9001?

No, but quality standards such as ISO9001 often require a business to identify, evaluate, and address risks, FMEA may be used as part of a business risk analysis.

Final Thoughts on Failure Mode and Effects Analysis

If you want to minimize the risk of a defect ever reaching your customer then FMEA is a proven qualitative and systematic approach that delivers real results.

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