FMEA: how it is done and practical examples

Core tools

written by Fulvio Boselli

9 February 2022

What is FMEA Analysis

FMEA is used for the systematic analysis of risk in complex systems or processes. The purpose of the application is to recognise, understand, limit and remedy potential weaknesses and risks and thus avoid errors.

FMEA (Failure Mode and Effects Analysis) is a team-oriented analysis that is used to find potential sources of errors in products or processes at an early stage, to recognise their importance and to evaluate them in order to derive appropriate preventive measures to avoid them if necessary. In this way, high control and error costs can be avoided or significantly reduced.

This methodology allows

  • Identify in advance possible failure or defect modes in processes.
  • The negative effects on plants and processes in the event of failures.
  • Plan strategies to prevent identified faults/defects or minimise their negative effects.

The Origin of FMEA Analysis

FMEA analysis was first used in the 1940s by the US Armed Forces to predict and minimise the negative effects in the event of an operational failure.

Once World War II was over, it was forgotten for some 20 years, only to be revived in the 1960s by theautomotive industrywhich was going through a period of very high competitiveness and therefore needed systems to optimise production and 'beat' the competition.

The FMEA methodology

FMEA analysis is a tool that allows an effective and thorough process analysisfrom the perspective of containment of the risk of failure o defects.

"Failure ModeIt indicates the ways in which any part of the processes could fail. Failures are errors or defects, particularly those affecting the end customer. Faults/errors/defects may be potential or actual.

"Effects AnalysisThis refers to the identification of potential consequences of failures, both at the level of internal company procedures and at the level of the company's reputation with the customer.

When to use FMEA Analysis

Ideally, FMEA analysis should be used during the early stages of design conceptualisation of a process or product, then during the design or redesign process.

This analysis is best used in the development of new products and processes or when these need to be modified and adapted. The strategy that errors should be avoided is pursued.

This means that risk assessments showing in sub-areas where more attention should be paid to the error prevention.

This level of awareness and attention will lead to the reduction of errors improving the quality of the product sent to the customer.

In detail, it is recommended to use this approach in the following cases:

  • When a process, product or service is designed or redesigned, after the implementation of the quality function (QFD - Quality Function Deployment)
  • When an existing process, product or service is applied in a new way.
  • Before developing control plans for a new or modified process.
  • When improvement objectives are planned for an existing process, product or service.
  • When analysing the failures of an existing process, product or service.
  • Periodically throughout the duration of the process, product or service.

What is FMEA Analysis for and what are the benefits?

This type of analysis refers to control procedures to maintain the health of processes and plants efficiently

It is used by ISO quality management consultants (ISO 31000) and experts in Risk Management to analyse all KRI (Key Risk Indicator) that jeopardise the organisational structure.

The structured approach of theFMEA analysis helps to anticipate the potential failures in the production or design of a product or process.

FMEA analysis enables the identification and prioritise failures based on the severity of their consequences, the frequency with which they occur and the ease with which they are detectable. You can then act to limit or prevent failures, starting with the most serious ones.

Here are the main reasons why many companies use FMEA:

Increased business efficiency

FMEA analysis increases business efficiency because it improves staff response times if the faults predicted in the analysis actually happen.

This increase in reaction/prevention speed allows the effects of faults, defects or errors that may occur to be limited.

Less repair costs

FMEA analysis allows equipment, machinery and systems to be approached proactively. Predicting when a machine will fail, rather than waiting for it to fail and thus increasing the probability of future breakdowns, allows maintenance to be planned at the optimum time.

More uptime

A machine/system that breaks down slows down production, which increases business losses. The procedures programmed by Analysis enable the team to intervene in the right way, as soon as possible. In this way, the team avoids adding human error to the breakdown and decreases the waiting time for intervention to resolve the situation. This means that uptime increases.

Increased safety for workers

Worker safety is a priority for every company, but companies themselves are not always aware of all the safety risks that exist in their various departments. The FMEA analysis makes it possible to identify worker safety risks and then implement safety measures.

Increasing the speed of response to problems

FMEA analysis allows problems to be solved quickly by applying the procedures decided upon and documented in the analysis. Having documented methods helps all personnel know exactly what to do and when, drastically decreasing the risk of errors and improving business efficiency.

Industries that use FMEA regularly

FMEA brings benefits to all companies, in all sectors. But there are sectors that implement it more than others and for longer, precisely because they are sectors that have been implementing strategies for improving business efficiency for some time. From these sectors, it is possible to learn why this analysis was implemented and what benefits it is bringing.

Software Development

FMEA analysis is often used in the software development sector, because it is a sector with great competition and whose products are used by many end users, where production errors can therefore affect brand reputation and consequently product sales.

Implementing an FMEA analysis system allows you to improve customer service, produce reliable software, reduce the cost of quality, cost and defect density.

Production

Large companies in the manufacturing industry have been using FMEA analysis for years to anticipate potential product assembly and production failures and to prevent collective action, which can also be very costly.

The use of FMEA analysis enables the production of reliable, high-quality products that meet customers' quality expectations.

Transport and logistics

The transport and logistics sector has inherent difficulties arising from the natural variability of transport systems. FMEA analysis makes it possible to anticipate errors and take measures to avoid them or avoid their consequences, enabling products to be delivered reliably.

The transport and logistics industry also uses FMEA analysis to assess supply chains in order to ensure quality service.

Agriculture

Companies in the agricultural sector rely on FMEA analysis to assess environmental risks, production risks, machinery failures and manage product quality.

This is important for environmental, ethical and legal considerations.

Design FMEA Analysis (DFMEA) vs. Process FMEA Analysis (PFMEA)

There are two methods of FMEA analysis:

  • The analysis Design FMEA
  • The analysis Process FMEA

The main difference between these two methods is expressed by their names. The methodology FMEA design focuses on creation of reliable productswhile the methodology Process FMEA focuses on development of reliable processes.

Although they can be used independently, they are often used together as part of a company's risk and failure analysis process. This is because both product design and business processes are at risk of failure and error, and both contribute to overall business quality.

If an organisation is committed to implementing continuous improvement, it must use both types of FMEA analysis, periodically.

How is an FMEA Analysis carried out?

Conducting an FMEA Analysis is a complex process that requires various professional figuresnot only the management level and consultants.

We have prepared a FMEA analysis model downloadable in ExcelTo download it, go to your personal area in the download section. The template we have prepared is completely free of charge!

First of all, let us make a list of definitions useful for FMEA analysis:

  • RiskThe risk is the failure, defect or damage that could occur;
  • Gravity (ranked in numbers from 1 to 10): the severity is how much the risk (failure/defect/error) could damage the company if it occurs;
  • Probability of occurrence (ranked in numbers from 1 to 10): the probability of occurrence is the likelihood that the risk will happen, e.g. a fault that occurs every time the machine is switched on is very likely, while a fault that could happen but never did is unlikely;
  • Probability of detection (ranked in numbers from 1 to 10): the probability of detection is how effective the company's control systems are in detecting the error/fault if it occurs;
  • Risk PriorityRisk priority is a combination of severity, probability of occurrence and detection. To obtain the risk priority, it is necessary to multiply the risk x the probability of occurrence x the probability of detection;
  • Risk Management InterventionsRisk management interventions are all interventions that can be done to mitigate the effects of risk if it occurs;
  • Interventions to prevent risk: interventions to prevent risk are all interventions to prevent the occurrence of risk;

How is an FMEA Analysis carried out?

FMEA Analysis - Step 1: Preparation for Analysis and Team Selection

The preparation work involves the collection and creation of all the documents required for the analysis. Since FMEA Analysis can be done at any point in the development process and on any business process, it is very important to include in the FMEA Analysis process all those who work on a given product or are part of a given process.

There is often a tendency to ignore production staff, but the production phase is precisely where failures, errors or defects occur most often. That is why it is very important to also involve the production staff.

FMEA analysis - Step 2: Data collection for analysis

When analysing faults, every possibility of error must be investigated. It is essential to bring as many cases as possible and all necessary documentation to the attention of all participants. Preparatory documents should include:

  • Process map
  • Parameter Diagram
  • Perimeter/block diagram
  • Listing of historical faults
  • Pest/Pestel analysis
  • SWOT analysis
  • Pareto Diagram
  • Ishikawa diagram
  • Process Flow Charts
  • Non-conformities detected
  • etc

Another important step before commencing an FMEA analysis is to determine the As-Is status of the product/process:

  • Requirements to be included
  • Design and/or process assumptions
  • Preliminary bill of materials / components
  • Known causes from surrogate products
  • Possible causes of interfaces
  • Potential causes resulting from design choices
  • Possible causes of noise and environments
  • Previous FMEAs
  • Previous test and control methods used on similar products

It is also important, in the case of an FMEA Design Analysis, to also bring in a set of documentation on quality and customer requirements, so that one is always aware of what standards the product must be measured against.

FMEA Analysis - Step 3: Defining Faults, Estimating Effects and Causes

The first step for the team to take to begin an FMEA analysis is to get together to focus on the debate that will ensue.

A brainstorming process will then begin in which the possible risks associated with the various subjects under analysis (a particular process, a piece of machinery, the entire company, a new product, etc.) will be written down.

It will be necessary to make everyone aware of the problems caused by failure, to go over the risks and problems related to different aspects (personnel safety, inefficiency, production stoppage, company costs, etc.) with the various team members.

Everyone needs to be aware of what it might mean to have a breakdown of a particular process or plant and what the risks associated with it might be

At the end of this brainstorming, the risks will be examined individually.

FMEA Analysis - Step 4: Prioritisation of Faults, Identification and Rating of Faults and Damage

All identified risks will be assigned a priority score. This system will make it possible to understand exactly which risks are most important and which are the least urgent to correct.

IMAGE FMEA 5 STEPS

This score will be calculated by multiplying the 3 values listed below:

  • Probability (P): How likely is it that any kind of error will occur or that there is a risk of it?
  • Gravity (G) - What is the level of severity, what is the effect of the occurrence of the error or the occurrence of the risk?
  • Detection (R): How likely is it that the occurrence of the error will be detected during checks in order to prevent it from happening?

Compilation form for calculating the risk score

IMAGE FMEA analysis example of table for RPN impact assessment

FMEA analysis example table for RPN impact assessment - Headvisor Brescia Bergamo and Milan

FMEA analysis - Step 5: Define actions to prevent and mitigate risks

Once the risks have been established and prioritised, it is time to identify preventive and corrective actions. A big part of preventive actions is to understand which risks do not have detection systems and to implement strategies to detect them.

  • Risk prevention strategiesPrevention strategies include all possible actions to be taken to prevent the risk from happening. An example could be scheduling maintenance for a machine that frequently has breakdowns. This prevents breakdowns and thus production stoppages;
  • Risk management strategiesAll these strategies are geared towards managing the risk once it happens. An example would be to train qualified personnel to repair a machine that keeps breaking down;

It is important that the team strives to identify at least one prevention strategy and one management strategy for each identified risk.

FMEA analysis - Step 6: Re-prioritisation of risks and closure of the FMEA analysis

After the identification of the risk prevention and management systems, it is time to re-prioritise the risks and close the FMEA Analysis, comparing it with the previous FMEA Analyses (if any) made.

Comparison with previous analyses serves to:

  • verify that all risks have been given the correct importance
  • verify that the appropriate scores have been awarded
  • verify that all risk management/prevention systems are in place
  • analysing how the risks, processes or design of a new product have changed over time

Once the comparison has been made, it is correct to make a new analysis on the priority of the risk: taking the document drawn up with all the scores, it is necessary to analyse each individual risk and review its priority rating to ensure that it is correct.

Once the whole team is in agreement, the FMEA document is closed and shared with management.

Management's analysis of FMEA documents

Consultants and company managers must review the FMEA analysis to understand the risks identified and review the risk priority scores.

Example of FMEA Analysis

Let us assess the risk through a practical example of a table. In the following FMEA example, we want to describe the severity of a production error on the supply to a customer.

The variables are the level of risk that the customer may obtain less than perfect parts up to serious financial damage in the case of a strategic and completely wrong delivery.

Example FMEA - Determination of risk parameters

The following parameters are determined for each error/risk:

  • Probability (P): How likely is it that any kind of error will occur or that there is a risk of it?
  • Gravity (G) - What is the level of severity, what is the effect of the occurrence of the error or the occurrence of the risk?
  • Detection (R): How likely is it that the occurrence of the error will be detected during checks in order to prevent it from happening?

Each of these three variables is assigned a value from the following rating scale:

IMAGE FMEA analysis example table for RPN calculation

FMEA analysis example table for RPN calculation - Headvisor Brescia Bergamo and Milan

Determination of RPN - Risk Priority Number

In order to express and assess potential risk, a Risk Priority Number (RPN) is now formed. The following applies:

  • RPN = P x G x R

This can result in risk priority numbers between 1 and 1,000.

The higher the RPN, the greater the unacceptability of the error or associated risk. The value that RPN expresses can hardly be derived from an automatic diagnostic level, it is rather derived from subjective evaluations and calculated empirically.

Of course, it also depends on the type of process.

When analysing a business-critical process, it is certainly necessary to select different parameters than a supporting or ancillary process.

The following table shows a possible evaluation of a practical consequence of collecting the parameters of an RPN value:

FMEA analysis example table for RPN impact assessment

FMEA analysis example table for RPN impact assessment - Headvisor Brescia Bergamo and Milan

FMEA example of process implementation

In the following example, some critical elements that can affect machine utilisation and loss of efficiency were detected from bar turning centres.

The elements of risk are as diverse as tooling, tool assembly or the use of incorrect or non-compliant raw materials. Here are some examples:

  • Shaft breakage
  • Bar not aligned
  • Incorrect bar diameter
  • Wrong steel quality Barrame
  • Incorrect tool assembly
  • Shift Change
  • etc.

The analysis is divided into 2 stages in order to detect criticalities in the first part (as described in detail above) and the simultaneous implementation of all necessary corrective measures. The expected result is to follow up risk reduction with targeted actions.

FMEA analysis example table for RPN impact assessment

FMEA analysis example table for RPN impact assessment - Headvisor Brescia Bergamo and Milan

In the detailed case, the criticality of incorrect material is reduced through a double check by both the logistics operator and the machine operator in order to reduce the risk of incorrect material thanks to the adoption of barcodes before being put in the car.

Similarly, they are empowered contact persons for the training of personnel in the measurement or visual inspection of the installation. This responsibility is achieved through the adoption of a Self Audit form at the end of each set-up and with the name and signature of the person responsible for the set-up indicated. This increases the level of control and identifies any shortcomings in the management of personnel responsibilities.

This example shows how following an initial detection of critical issues, a system of efficiency improvement was then implemented with the involvement of different contact persons (HR managers, toolmakers, logistics personnel and machine operators) once again the FMEA system resulted in the management of a cohesive team in the search for shared solutions.

Considerations:

Notice how in the Gravity column (G) the values have not been touched at all. In fact, the Severity level, although subjectively assigned, must always remain the same. Except in cases where extraneous contextual factors come into play, the severity level is the constant element in the analysis.

On the other hand, the variable and control elements that can govern efficiency through FMEA analysis are certainly the level of Probability (P) and Detectability (R).

It is precisely on these 2 elements that the efficiency process must operate, reducing the variability of the process (and thus operating on the Probability factor) and increasing control (to improve the Detectability factor).

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